WO2004011966A1

WO2004011966A1 - Curved surface lens and display

Info

Publication number: WO2004011966A1
Application number: PCT/JP2003/009488
Authority: WO
Inventors: Yutaka Egawa
Original assignee: Comoc Corporation
Priority date: 2002-07-25
Filing date: 2003-07-25
Publication date: 2004-02-05
Also published as: JP2006053166A; AU2003248130A1

Abstract

A curved surface lens and a stereoscopic display in which a two-dimensional image can be viewed as a stereoscopic image having a depth while suppressing distortion. The display comprises a curved surface lens where smoothly curved basic lens surfaces repeating a convex surface and a concave surface alternately are arranged in multilayer or a specified condition, e.g. the varying direction of curved surface, is required for to the lens surface, and a two-dimensional display image located at a position separated from the curved surface lens, wherein a viewer can view the two-dimensional display image as a stereoscopic image through the curved surface lens by facing the two-dimensional display image disposed oppositely to the curved surface lens.

Description

Description Curved lens and display device

The present invention relates to a video system including a display device such as a signboard, a signboard, a display tower, etc., which is placed indoors or outdoors, an electronic display such as a television receiver, a monitor of a personal computer, and a movie. The present invention relates to a display device for displaying a stereoscopic image with a perspective. Further, the present invention relates to a curved lens used for the display device. Background art

There are already a number of well-known methods for viewing two-dimensional images such as photographs and printed matter as three-dimensional images, and they are organized and presented in Takayoshi Ohkoshi's “Three-dimensional image engineering”. A typical example is a photograph (or a depiction image) of a target object taken from two different directions, which is individually viewed with the left eye and the right eye. is there. In this method, it is necessary to include a device made so that different images can be seen by the left and right eyes, which is not suitable for ordinary signs and guide boards.

As another example, a method of viewing a two-dimensional image as a three-dimensional image using a lenticular plate is well known. This is a strip of a two-dimensional image of a continuous pattern viewed from a plurality of different directions on the back side, which is the focal plane of a lenticular plate in which a number of vertically long, semi-cylindrical lenses are arranged horizontally. The display image of a discontinuous pattern, which is formed by cutting strips of different directions in the shape of a rectangle (elongated rectangle) and arranging the strips in different directions in order in the horizontal direction, is arranged through a micro-cylindrical lens that forms a lenticular plate. The design seen by the right or left eye is a collection of striped designs of the design seen from a specific direction, and the design seen by the right eye and the left eye is the design seen from different directions. This is a method of recognizing as a three-dimensional image.

The displayed image in this method is that the whole image is not a single continuous pattern. This is a vertical striped discontinuous special image in which independent strip-shaped designs are continuously connected. The position of this strip-shaped design must be precisely located at a position very close to the focal plane of the lenticular plate in the depth direction, and the small cylindrical lens constituting the lenticular plate must also be placed in the horizontal direction. Strict positional accuracy is required in the above positional relationship. As described above, it is necessary to create a special image, and strict conditions are imposed on the alignment between the image and the lens. Therefore, there are drawbacks such as being expensive and not easy to replace.

Furthermore, it is necessary that the strip pattern seen by the left eye and the strip pattern seen by the right eye be distinguished from each other when viewed from different positions, and the distance from the observer to the display device, the viewing angle at which the observer looks at the display device, etc. There are limited disadvantages.

Furthermore, Takashi Ohkoshi's “Three-Dimensional Image Engineering” has the following description as an insightful outline for stereoscopic images.

"If you look at a photograph with one eye through a magnifying glass, you will see a surprisingly strong stereoscopic effect in the image of one eye with an appropriate positional relationship."

The reason is explained in the same book as follows.

`` Binocular parallax '' and `` convergence '' of the eye do not function because it is one eye, but only the accommodation function of the eye is effective, and as a result of shifting the position of the virtual image from the position of the actual image, He loses clues as to whether it is flat or three-dimensional, and the three-dimensional and the brain judge based on experience. "

In other words, it is explained that when an image is formed at a position shifted from the position of the actual image, the brain perceives three-dimensionally due to an illusion.

The display image viewed through the spectacles is a two-dimensional image such as a photograph that is commonly viewed as a continuous whole image. It is a kind of so-called ordinary photograph or picture.

A three-dimensional display device utilizing the phenomenon of appearance of a sense of sensation due to the accommodation function of the eye that appears when viewing through one eye through this spectacle (magnifying glass) has been proposed by the inventor of the present invention in Japanese Patent Application Nos. 11-218313 and 11-218313. It is presented in Hei 11—319176, Japanese Patent Application 2000—53954, Japanese Patent Application 2000—156608, Japanese Patent Application 2000-162231, Japanese Patent Application 2000—225557, and Japanese Patent Application 2000-232564. Detailed explanations of these are omitted, but the outline is as follows. When viewed through a micro-lens array in which micro lenses are arranged on one side, placed in front of the display image, the image created by each micro lens is synthesized as new pixels, and it is separated from the position of the display image. As a result of forming the entire image at a place, a three-dimensional display without distortion in the left, right, up and down directions is performed.

The display image used here is a two-dimensional display image composed of a continuous pattern like a photograph commonly seen in general. Hereinafter, unless otherwise specified, the term “display image” or “two-dimensional display image” refers to a two-dimensional display image consisting of a continuous pattern such as a photograph generally seen.

The above-described stereoscopic display by the microlens array was based on the principle of the accommodation function of the eye that appears when viewing with one eye through a magnifying glass.

However, an image viewed with the left and right eyes through a magnifying glass, that is, a lens, has a stronger three-dimensional effect than an image viewed with one eye, and the appearance appears to be greatly related to the lens configuration. Knowledge was obtained.

An object of the present invention is to provide a new display device in which a stronger three-dimensional effect appears based on the newly obtained knowledge. In particular, it is an object of the present invention to provide a display device that produces a relatively strong three-dimensional effect while minimizing image distortion that occurs, and a curved lens used therein. Disclosure of the invention

The present invention employs the following means in order to solve the above problems.

The curved lens according to claim 1 has a single smooth concave surface, a single smooth convex surface, or a surface 23 and a convex surface 22 that are alternately arranged as shown in FIGS. 1 to 4, for example. As a lens surface, or a single smooth concave surface, a single smooth flat surface, or a smooth curved surface in which concave and convex surfaces are alternately arranged. It has a Fresnel lens-type surface (see FIG. 4) having any of them as a generating surface, and the effective area or shape is rectangular. The lens surface or the generating surface has an arbitrary point. In the above, there is a direction having the largest curve change, and an angle formed by a plane including the direction with the largest curve change and perpendicular to the rectangle and one side of the rectangle is in a range of 30 degrees to 60 degrees. Here, the lens surface refers to a curved surface that forms a boundary between materials having different refractive indexes (including the atmosphere), that is, a curved surface that forms an outer surface of the lens and a boundary between materials having different refractive indexes.

Further, the shapes and dimensions of the convex and concave surfaces formed on the lens surface are various, and one convex or concave surface can have various curved surface distributions. The convex surface and the concave surface are convex and concave in a structural sense, and the ώ surface can be a convex lens or a concave lens depending on the refractive indices of both materials facing each other with the surface interposed therebetween. The same applies to the concave surface.

Except for special cases, the surface of the lens with convex or concave surfaces is invariant regardless of its location on both sides sandwiching this surface, so if curved surfaces of the same shape are structurally ώ, convex if concave, concave if concave This means that concave lenses are arranged. Here, the explanation is based on this premise.

Next, the arrangement of the convex surface and the concave surface will be described. The concave or convex surface can have various shapes and dimensional forces. Boundary regions also vary. The irregularities are not necessarily arranged in an orderly manner. In general, concave or convex surfaces may be arranged in two specific directions or I-dimensionally, and there may be some fluctuation or variation. The repetition interval of the array may be different in two specific directions. Also, the one-dimensional shape is not limited to a linear shape, and concave or convex surfaces may be arranged along the circumferential direction.

The convex and concave surfaces are usually arranged two-dimensionally on the lens surface, but some are arranged one-dimensionally. The one-dimensional array is, for example, an array such as a lenticular lens in which a large number of cylindrical cylindrical lenses are arrayed only in a predetermined direction. In this way, the concave or convex surface is arranged along one line. That is, when looking at a cross section along a predetermined direction, the distribution of concave or convex surfaces can be observed, but when looking at a cross section orthogonal to the predetermined direction, no change is observed. Also, two-dimensional refers to a state in which concave or convex surfaces are arranged in two specific directions in a plane. For example, assuming that two specific directions in the plane are orthogonal X and y directions, concave or convex surfaces are arranged in both the X direction and the y direction, and the concave surface when viewed from the z direction perpendicular to the X direction and the y direction. Or, the convex surfaces appear to be arranged in an array. If you look at the cross sections along two specific directions, you can observe the arrangement of the concave and convex surfaces. Further, the two specific directions may be a circumferential direction and a radial direction. The angle between the two specific directions is not necessarily a right angle such as 30 degrees. Further, the repetition interval of the array may be different in two specific directions. Also, the one-dimensional shape is not limited to a linear shape, and a concave or convex surface may be spirally arranged along the circumferential direction. In addition, the concave or convex surface may have various shapes and dimensions, and the boundary region may also be various.Therefore, the irregularities are not necessarily arranged in an orderly manner, and the concave or convex surface is generally formed in two or one specific direction. It should just be arranged. Further, the specific direction may be a direction along a meandering line. Further, it is needless to say that there may be some fluctuation or variation.

In the case of a curved lens, the surface including the X and y directions is a divergent surface, and the z direction perpendicular to the divergent surface is the thickness direction of the lens surface, and this thickness changes with the position of the divergent surface. The surface will undergo a curved change. Since the thickness is sufficiently small compared to the size of one side of the expanding surface, the curved lens is regarded as a flat surface, that is, an approximately rectangular surface, ignoring this thickness.

A lens whose surface is a Fresnel lens type surface (see Fig. 4) is equivalent to a lens whose surface is a generating surface. Therefore, the lens surface is a lens that changes slowly over a relatively wide range, and works as a lens without any part where the characteristics of the lens change rapidly with a change in location. If the lens surface is a Fresnel lens type, the thickness of the curved lens can be reduced.

For example, as shown in FIG. 1, it is easy to install a rectangular curved lens 10 so as to face a rectangular two-dimensional display image 11 which is generally widely distributed so that each side is parallel to each other. In this state, the angle that forms the largest curve change with one side of the rectangular surface of the curved lens is in the range of 30 to 60 degrees, so that the lens surface (see Figs. 2 and 3) is in the horizontal direction of the observer's eye. Therefore, there is a curved change in both the vertical direction and the vertical direction, and there is no only a curved change in the vertical direction. The largest change in the curve means that the change in the curve, including the manufacturing variation, is substantially substantially maximum.

That is, the displayed image on the lens surface is enlarged or reduced not only in the horizontal direction but also in the vertical direction, and the position of the image in the depth direction changes depending on the location of the image. The degree of enlargement or reduction differs depending on the location of the lens surface, and reaches the right and left eyes. The light from the displayed image that arrives has a different path, resulting in a difference between the images formed in the retina of the right eye and the left eye.

As a result, the image appears to be deformed in the oblique direction, and the image looks deformed in the depth direction. In addition, since the lens surface changes smoothly and gradually, the image deforms smoothly and gently without any sudden change.

The curved lens described in claim 2 has a single smooth concave surface, a single smooth convex surface, or a concave surface and a convex surface alternately arranged as shown in FIGS. 11 and 12, for example. Any of the smooth curved surfaces is defined as a virtual array surface V, and the small convex surface and the small concave surface having a smaller area of a portion overlapping each of the regions with respect to the area of each of the convex or concave regions constituting the virtual array surface. A lens surface having a smooth curved surface alternately arranged along the virtual array surface, or a portion overlapping each of the regions with respect to the area of each of the convex or concave regions constituting the virtual array surface The lens surface is a Fresnel lens type surface having a smooth curved surface, which is a mother curved surface, in which small convex surfaces and small concave surfaces having a small area are alternately arranged along the virtual arrangement surface. Here, if the same area range as the individual convex or concave surfaces constituting the virtual array surface is considered, the lens surface has the same shape and the same position as the virtual lens surface N at the same position as the virtual array surface. Can be considered. On the other hand, if the same range of area as the small concave surface or the small convex surface arranged on the virtual array surface is to be considered, the lens surface is approximately a plane with the small convex surface and the small concave surface arranged on the virtual array surface. It can be regarded as a virtual lens surface M alternately arranged in a shape. Therefore, the lens surface can be approximately regarded as a multilayer of the virtual lens surface M and the virtual lens surface N.

In addition, the area where the convex surface or the concave surface overlaps indicates the area of the region facing and facing the concave or convex surface to be compared.

A lens having a boundary surface of a Fresnel lens type as a lens surface is equivalent to a lens having a generating surface as a lens surface.

As is clear from the above description, both the virtual lens surface N and the virtual lens surface M are either a single concave surface or a single convex surface or a smooth curved surface, or the concave and convex surfaces are It can be regarded as a smooth curved surface that is arranged alternately. Light from one point of the displayed image reaches the right and left eyes through different positions on the lens surface. Therefore, when looking at the two-dimensional display image placed facing the curved lens through the curved lens, there is a difference between the images formed in the retinas of the right eye and the left eye. The difference is that the difference between the small areas corresponding to the concave surface and the convex surface constituting the lens surface is arranged at the same interval as the repetition interval between the concave surface and the convex surface. Therefore, an image that is viewed through both the virtual lens surface M and the virtual lens surface N has a large difference in the repetition interval due to the virtual lens surface N and a small difference in the repetition interval due to the virtual lens surface M. The difference and will coexist.

Regarding the distortion generated in the image, the distortion caused by the virtual lens surface N has a large repetition interval, and the distortion caused by the virtual lens surface M has a narrow repetition interval. Since both the virtual lens surface N and the virtual lens surface M are smooth curved surfaces, the distortion is smooth and there is no sharply changing distortion.

As described above, a three-dimensional effect can be felt both in an image part having a large area and in an image part having a small area, and the two parts are mutually strengthened to obtain a stronger three-dimensional effect. The image distortion caused by the virtual lens surface N and the virtual lens surface M has different repetition periods. Therefore, it is possible to avoid that the image distortions caused by the virtual lens surface N and the virtual lens surface M reinforce each other.

As a result, it is possible to suppress the distortion of the image and further enhance the appearance of the three-dimensional effect.

Further, since the lens surface is a smooth curved surface, the deformation of the image is a smooth deformation, and is not accompanied by a sudden deformation, so that the image quality can be maintained at a certain level.

If the lens surface is of a Fresnel lens type, the thickness of the curved lens can be reduced. The invention described in claim 3 is the curved lens according to claim 2, wherein the small convex surface and the small concave surface are arranged at a similar size and a repetition interval; and It is preferable that the state of the change in the surface gradient is approximately the same.

Both the small concave surface and the small convex surface that constitute the lens surface are at the same interval, and the shape of the curved surface change between the small concave surface and the small convex surface is almost the same, so that the distortion created by the small concave surface and the small convex surface is also about the same. It can be seen as an image in which the magnitude of the distortion is suppressed without one becoming larger than the other. The invention described in claim 4 is the curved lens according to claim 2 or 3, wherein the area of each of the convex and concave regions constituting the virtual array surface is the same as that of the curved lens. It is preferable that the area of the portion where the small convex surface and the small concave surface overlap each of the regions is 1 to 4 or less.

In the case where a lens surface in which convex and concave surfaces are repeatedly arranged at relatively wide intervals and a lens surface in which small convex and small concave surfaces are repeatedly arranged at relatively narrow intervals are superposed in multiple layers, the right eye and the left eye Differences occur over a relatively wide range in the area corresponding to the widely spaced lens surface in the image formed on the retina of the eye, and are repeated with a relatively narrow cycle in the area corresponding to the closely spaced lens surface. Such differences occur. Also, the period of the image distortion is different. As described above, when there is a difference in the width of the convex surface or the concave surface, it is possible to reduce the overlapping of the images formed by the two lens surfaces, and to avoid mutually reinforcing the overall image deformation.

The curved lens described in claim 5 has, for example, a single smooth concave surface, a single smooth convex surface, or a concave surface and a convex surface alternately arranged as shown in FIGS. 6, 7, and 8. Either of the smooth curved surfaces thus obtained is defined as a virtual array surface V, and the area of each of the convex or concave regions constituting the virtual array surface is effectively a portion overlapping with the respective regions. A lens having a curved surface formed by arranging only a minute convex surface or only a minute concave surface having a sufficiently small area along the virtual array surface, or an area of each of the convex surface and the concave surface constituting the virtual array surface. Effectively, a surface of a Fresnel lens type having a curved surface formed by arranging only a minute convex surface or only a minute concave surface along the virtual arrangement surface with a sufficiently small area of a portion overlapping with each of the regions is used. It has as a lens surface.

Here, the term “effectively only a minute convex surface or only a minute concave surface” means a case where something other than a minute convex surface or a minute concave surface, including manufacturing variations, is slightly mixed. As is apparent from the description of Claim 2, the lens surface is approximately the same shape as the virtual array surface and the virtual lens surface N at the same position and the minute convex surface or minute concave surface are arranged in a plane. It can be approximated that the virtual lens surface M thus obtained is multi-layered. Hereinafter, the minute convex surface and the minute concave surface are collectively referred to as a minute curved surface.

In addition, a lens having a boundary surface of a Fresnel lens type as a lens surface has a base curved surface as a lens. This is equivalent to a lens having a surface.

For this reason, the image viewed from the two-dimensional display image placed facing the curved lens via the curved lens is deformed in the left, right, up and down directions by the virtual lens surface N. The degree of enlargement or reduction differs depending on the location of the lens surface. Due to this, light from the display image reaching the right eye and the left eye has different paths, so that the images formed on the retinas of the right eye and the left eye are different. Further, the position of the image in the depth direction also changes depending on the location. In addition, since the virtual lens surface N changes smoothly, the image in the left, right, up, and down directions also becomes a smoothly deformed image without abrupt change.

The virtual lens surface M is a group of minute curved surfaces having a sufficiently small area.These minute curved surfaces act as independent minute lenses, and the image created by each minute lens becomes a new pixel, thereby forming a new pixel. It constitutes the whole picture. Therefore, the virtual lens surface M functions to further change only the position in the depth direction of the image, which does not have the function of enlarging / reducing the left / right and up / down directions with respect to the entire image formed by the virtual lens surface N.

Therefore, the small convex surface or the small circular surface can be regarded as a point small enough to be regarded as a pixel.In terms of function, the small convex surface or the small concave surface in claim 2 is relatively small in the image formed on the retina. Unlike a small convex surface or a small concave surface, a difference that is repeated in a narrow range is caused, but only a position in a depth direction of an image is changed.

By making the lens surface a Fresnel lens type lens, the thickness of the curved lens can be reduced.

The invention according to claim 6 is the curved lens according to claim 5, wherein the area of the minute convex surface or the minute concave surface overlaps with each area with respect to the area of the effective area. Is preferably 1/100 or less. The image of the minute convex surface or the minute concave surface functions as a pixel of the whole image. Therefore, the smaller the minute convex surface or minute concave surface, the smaller the pixel, and the higher the resolution of the whole image.

The curved lens described in claim 7 has a single smooth concave surface, a single smooth convex surface, or a concave surface and a convex surface alternately arranged as shown in FIGS. 10 and 13, for example. Force to use any of the smooth curved surfaces as the first lens surface A, or a single smooth concave surface, a single smooth convex surface, or alternating concave and convex surfaces The first lens surface A is a Fresnel lens type having any one of the smooth curved surfaces as a base curved surface, and each of the first and second lens surfaces is defined by the area of the convex or concave surface constituting the first lens surface. The second lens surface B is a smooth curved surface formed by alternately arranging small convex surfaces and small concave surfaces having a small area of an overlapping portion with the first lens surface and the second lens surface. .

Here, a lens having a boundary surface of the Fresnel lens type as a lens surface is equivalent to a lens having a generating surface as a lens surface. Therefore, the first lens surface is a smooth curved surface, and works as a lens having no portion in which the characteristics of the lens suddenly change with a change in location. Since the lens surface is a Fresnel lens type, the thickness of the curved lens can be reduced.

The image distortion caused by the lens surface is an image in which a region having distortion corresponding to each convex surface and concave surface constituting the lens surface is repeated.

Therefore, when a two-dimensional display image is viewed through the curved lens according to the present invention, an image in which distortion over a relatively wide range is repeated by the first lens surface is obtained. In addition, since the second lens surface is a smooth curved surface, and the curved surface changes repeatedly in a relatively narrow range, distortion in a relatively narrow range is repeated by the second lens surface. Any of these image distortions caused by the first lens surface or the second lens surface does not change rapidly because the lens surface changes smoothly.

Thus, the image distortion caused by the first lens surface and the second lens surface is different between the first lens surface and the second lens surface, and the former causes distortion over a wider range. On the other hand, in the latter case, distortion occurs such that distortion in a narrower range is repeated. As described above, as a result of the difference in the range of image distortion that can be seen between the first lens surface and the second lens surface, it is possible to avoid compromising the overall image distortion. Also, since the lens surface is a smooth curved surface, the image distortion is smooth and does not involve abrupt deformation, so that the image quality can be maintained at a certain level.

In addition, as a result of the light from the display image reaching the right eye and the left eye having different paths, a difference occurs between images formed on the retina of the right eye and the left eye. In the portion corresponding to the first lens surface, a difference occurs in which the difference changes gradually over a relatively wide range, and in the portion corresponding to the second lens surface, the difference changes in a relatively narrow range. Around a narrow area This is a difference that is repeated as a period. For this reason, a three-dimensional effect can be felt both in an image part having a large area and in an image part having a small area, and the two parts are mutually strengthened to obtain a stronger three-dimensional effect.

The invention described in claim 8 is the curved lens according to claim 7, wherein the small convex surface and the small concave surface are arranged at a similar size and a repetition interval, and It is preferable that the state of the change in the surface gradient is approximately the same. Since the small concave surface and the small convex surface that constitute the lens surface are both at approximately the same interval, and the change in the curved surface between the small concave surface and the small convex surface is almost the same, the distortion created by the small concave surface and the small convex surface is also the same. , And one does not become larger than the other, and can be viewed as an image with reduced magnitude of distortion.

The invention described in claim 9 is the curved lens according to claim 7 or 8, wherein the area of each of the convex and concave regions constituting the first lens surface is as follows. It is preferable that the area of the portion where the small convex surface and the small concave surface overlap each of the regions is 1/4 or less.

When a lens surface having convex and concave surfaces repeatedly arranged at relatively wide intervals and a lens surface having small convex and small concave surfaces repeatedly arranged at relatively narrow intervals are superposed in multiple layers, the right eye and the left eye In the image formed on the retina of the eye, there is a difference that gradually changes over a relatively wide range at a portion corresponding to a lens surface at a wide interval, and a relatively narrow range at a portion corresponding to a lens surface at a narrow interval. Differences occur that are repeated. Also, the range of image distortion is different. In this way, when there is a difference between the area of the overlapping portion of the convex or concave surface and the area of the convex or concave surface to be compared, there is a portion where the difference between the binocular images is large and a portion where the difference is small. Acts to enhance the three-dimensional effect. In addition, it is possible to reduce the overlapping of the image distortions caused by the two lens surfaces, and to avoid mutually reinforcing the overall image deformation.

The curved lens according to claim 10 is, for example, as shown in FIG. 9, a single smooth concave surface, a single smooth convex surface, or a smooth curved surface in which concave and convex surfaces are alternately arranged. The surface of the Fresnel lens type with either of Effectively, only the minute convex surface or only the minute concave surface is arranged on the surface A, where the area of the portion overlapping with the respective regions is sufficiently small with respect to the area of each of the convex and concave regions constituting the first lens surface. Is a second lens surface B, and the first lens surface and the second lens surface are laminated.

Here, a lens having a boundary surface of the Fresnel lens type as a lens surface is equivalent to a lens having a generating surface as a lens surface. Therefore, the first lens surface can be regarded as a smooth lens surface in which concave surfaces and convex surfaces are alternately arranged. If the lens surface is a Fresnel lens type, the thickness of the curved lens can be reduced.

For this reason, the image of the two-dimensional display image placed by the curved lens facing the curved lens is deformed in the left, right, up, and down directions by the first lens surface. The position of the image in the depth direction also changes depending on the location. The degree of these deformations varies depending on the location where light reaching the eye passes through the lens surface, resulting in a difference between the images formed in the retina of the right eye and the left eye. Also, since the first lens surface changes smoothly, the deformation of the image in the left, right, up and down directions is also a smooth deformation without abrupt change.

The second lens surface is a collection of minute curved surfaces with a sufficiently small area, and these minute curved surfaces act as independent minute lenses, and the image created by each minute lens becomes a new pixel to constitute the entire image of the display image. Will do. Therefore, the second lens surface has a function of further changing only the position in the depth direction of the image, which does not have the function of enlarging / reducing the left / right and up / down directions with respect to the entire image formed by the first lens surface.

The repetition interval of the image distortion corresponds to the repetition interval of the surface forming the lens surface and the convex surface. The same applies to the repetition interval of the difference generated in the images formed in the retina of the right eye and the left eye.

The overall binocular image through a plurality of lens surfaces having different repetition intervals between the concave surface and the convex surface constituting the lens surface has a difference that repeats at a wide interval and a difference that repeats at a narrow interval. Also, the distortion of the image is such that the distortion is repeated at a wide interval and the distortion is repeated at a narrow interval.

The invention according to claim 11 is the curved surface lens according to claim 10, wherein an area of a portion where the minute convex surface or the minute concave surface overlaps with each of the regions with respect to an area of the effective region. It is preferably at most lZioo. Minute convex or fine The image of the small concave surface becomes a pixel of the whole image. Therefore, as the minute convex surface or minute concave surface becomes smaller, the pixel becomes smaller, and the resolution of the whole image is improved.

The curved lens described in claim 12 has a smooth lens surface in which concave and convex surfaces are alternately arranged as shown in FIGS. 10 and 13, or a concave and convex surface are alternately arranged. One or both of the surfaces of a Fresnel lens type having a smooth curved surface as a base curved surface are formed in a multilayer structure, and the repetition interval between the concave surface and the convex surface constituting the lens surface of each layer is different from that of the other layer. It is different from the repetition interval of the concave surface and the convex surface constituting the lens surface.

Here, a lens having a Fresnel lens type boundary surface as a lens curved surface is equivalent to a lens having a base curved surface as a lens curved surface. Therefore, any lens curved surface can be regarded as a smooth lens curved surface in which concave and convex surfaces are alternately arranged.

For this reason, the image of the two-dimensional display image placed by the curved lens facing the curved lens is deformed in the left, right, up and down directions by the lens curved surface. The position of the image in the depth direction also changes depending on the location. Since the degree of these deformations varies depending on where light reaching the eye passes through the curved surface of the lens, there is a difference between the images formed in the retina of the right eye and the left eye.

In addition, since these lens curved surfaces change smoothly, the deformation of the image in the left, right, up and down directions is a smooth deformation without abrupt change.

The repetition interval of the image distortion corresponds to the repetition interval of the concave surface and the convex surface constituting the lens curved surface. The same applies to the repetition interval of the difference that occurs in the images formed in the retina of the right eye and the left eye.

In a comprehensive image through a plurality of lens surfaces having different repetition intervals between the concave surface and the convex surface constituting the lens surface, there are differences that repeat at a wide interval and differences that repeat at a narrow interval. In addition, the distortion of the overall image coexists with the distortion repeated at wide intervals and the distortion repeated at narrow intervals.

Since the repetition interval between the concave and convex surfaces that compose each multiplexed lens curved surface is different, the image difference that occurs between the eyes changes gradually over a relatively wide range. There are some things that are repeated, so that you can feel a three-dimensional effect both in the image area with a large area and in the image area with a small area, Both enhance each other to give a stronger three-dimensional effect.

If the lens curved surface is a Fresnel lens type, the thickness of the curved lens can be reduced.

The curved surface lens according to claim 13 has, as shown in FIG. 14, for example, a lens surface A having a smooth curved surface formed by alternately arranging small convex surfaces or small concave surfaces, and has an area of an effective area. On the other hand, the area of each of the small convex surface and the small concave surface is 1/20 or less.

With this configuration, a large number of minute regions having a difference in size corresponding to the small convex surface or the small concave surface of the lens surface are distributed in the entire image. As a result, a three-dimensional effect with a sense of depth appears in the entire image.

The image formed by the curved lens placed facing the two-dimensional display image is deformed left and right and up and down by the lens surface, resulting in a difference between the images formed in the retinas of the right and left eyes. The difference between the images of the two eyes is formed by repeating the area with the difference generated corresponding to the small convex surface and the small concave surface constituting the lens surface. In this way, even in a case where a region with a difference between binocular images is distributed in the entire image, a three-dimensional effect with a sense of depth appears in the entire image. Also, as for the distortion, a distortion having a magnitude corresponding to the small convex surface and the small concave surface is distributed.

In addition, it is possible to bring about a difference between binocular images in which a difference in a relatively narrow range is repeated. As for the image distortion, the distortion in a relatively narrow range is repeated. Further, since both the small convex surface and the small concave surface of the lens surface are relatively narrow, the thickness of the curved lens can be reduced.

The display device according to claim 14 is, for example, as shown in FIG. 1, for observing a two-dimensional display image composed of a continuous pattern through the curved lens according to claims 1 to 13. A display screen 11 for displaying the two-dimensional display image and the curved lens 10 described above are provided so as to enable the display.

With this configuration, by placing the curved lens at an appropriate position facing the desired two-dimensional display image, a difference occurs between the images formed in the retina of the right eye and the left eye, and the two-dimensional display image has a sense of depth. It looks like a solid three-dimensional image.

The curved lens described in claims 1 to 13 has a single smooth concave surface or a single smooth convex force or a concave and convex surface alternately arranged. There is a lens surface A that can be regarded as any of the smooth curved surfaces. Due to the lens surface A, the image of the display image viewed through the curved lens is distorted in the left, right, up and down directions, and the position of the image in the depth direction changes depending on the location. Since the lens surface A is a smooth curved surface, the image of the displayed image is gradually deformed and does not suddenly deform in a part. In addition, the light that has exited one point of the displayed image reaches the right and left eyes through different locations on the lens surface A, resulting in a difference in the images formed in the retinas of the right and left eyes, resulting in a sense of depth. Is generated. According to a fifteenth aspect of the present invention, it is preferable that the display device according to the fourteenth aspect of the present invention includes a communication image or broadcast image receiving means. With this configuration, a communication image or a broadcast image can be used, and a use area is greatly expanded. The invention described in claim 16 is the display device according to claim 14 or 15, wherein the curved lens 10 and the display screen 11 are, as shown in FIG. It is preferable to provide a means 12 for holding at a distance of.

In order to obtain a stronger three-dimensional effect, the distance between the lens surface and the displayed image is important. Even if it is refracted on the lens surface, if the distance to the display image is short, the difference in the position of the display image due to the refraction will be small. Therefore, it is essential that the displayed image is away from the lens surface, which also requires a certain distance. The means for holding the curved lens and the display screen at a predetermined distance is, for example, a portable telephone in which a curved lens is sandwiched between a display screen and a lid, and a flip-up mechanism is provided between the display screen and the curved lens. When the lid is opened, the distance between the display screen and the curved lens may be increased by a flip-up mechanism.

The invention described in claim 17 is preferably the display device according to claim 16, wherein the predetermined distance is adjustable. The required degree of curve change of the lens surface, the required distance between the lens surface and the displayed image, also depends on the position of the observer. By adjusting the distance between the display image and the curved lens, it is possible to adjust the degree of appearance of a three-dimensional effect due to the difference in distance between the observer and the display device. Further, the distance between the display image and the curved lens may be adjusted by curving the curved lens to enhance the three-dimensional effect.

The invention described in claim 18 is described in claim 16 or 17. In the above display device, it is preferable that the predetermined distance is not more than 12 times a focal length of the curved lens. When the distance of the displayed image from the lens surface is less than or equal to 12 of the focal length, the magnification is 2 times or less when the lens characteristic is a convex lens. In the case where the lens characteristic is a concave lens, the reduction rate does not become 0.66 or less, and the generated distortion can be limited.

A structure for a display device according to claim 19, comprising a holding mechanism for holding the curved lens and the display screen in the display device according to claims 14 to 18. (See Fig. 1).

Either a curved lens or an image display screen may be attached to the holding mechanism first. The distribution may be performed with the curved lens attached first. This application is based on Japanese Patent Application No. 2002-216272 filed on July 25, 2002 in Japan, the contents of which are incorporated in and form a part of the present application.

Also, the present invention may be more completely understood by the following detailed description. Further areas of applicability of the present invention will become apparent from the detailed description provided below. However, the detailed description and specific examples are preferred embodiments of the present invention, and are described for illustrative purposes only. From this detailed description, various changes and modifications will be apparent to those skilled in the art without departing from the spirit and scope of the present invention.

Applicant may disclose any of the disclosed modifications and alternatives which are not intended to be publicly available to any of the described embodiments and which may not be literally within the scope of the claims. It is part of the invention under discussion. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a display device according to a first embodiment, in which a curved lens is arranged to face a two-dimensional display image. It is also a perspective view of the display device according to the second to twelfth embodiments in which the form of the curved lens is changed.

FIG. 2 is a perspective view of a curved lens used for the display device according to the first embodiment.

FIG. 3 is a cross-sectional view of a curved lens used in the display device according to the first embodiment. You.

FIG. 4 is a cross-sectional view and a front view of a curved lens used in the display device according to the second embodiment. This curved lens is a lens of the Fresnel lens type, and also shows the base curved surface.

FIG. 5 is a cross-sectional view of a curved lens used for the display device according to the third embodiment.

FIG. 6 is a sectional view of a curved lens used for the display device according to the fourth embodiment.

FIG. 7 is a cross-sectional view of a curved lens used for the display device according to the fifth embodiment.

FIG. 8 is a cross-sectional view of a curved lens used for the display device according to the sixth embodiment.

FIG. 9 is a sectional view of a curved lens used for the display device according to the seventh embodiment.

FIG. 10 is a cross-sectional view of a curved lens used for the display device according to the eighth embodiment.

FIG. 11 is a sectional view of a curved lens used for the display device according to the ninth embodiment.

FIG. 12 is a sectional view of a curved lens used for a display device according to the tenth embodiment.

FIG. 13 is a sectional view of a curved lens used for the display device according to the eleventh embodiment.

FIG. 14 is a sectional view of a curved lens used for the display device according to the twelfth embodiment.

FIG. 15 shows a mobile phone according to a thirteenth embodiment in which a curved lens is arranged so as to face a display element.

FIG. 16 shows a mobile phone according to a fourteenth embodiment in which a curved lens is arranged so as to face a display element. BEST MODE FOR CARRYING OUT THE INVENTION

Prior to the detailed description of each embodiment, a new finding in which an image viewed by both eyes through a lens gives a three-dimensional effect will be described.

It has already been pointed out and well known that a stereoscopic effect appears in the image viewed with one eye through a magnifying glass, and this is due to the "adjustment" function of the eye. Looking at this with both eyes gives a stronger sense of standing. This is presumed to be due to the fact that another function is acting in addition to the function of the “adjustment function” of the eye, which produces a three-dimensional effect even with one eye.

The light from one point of the displayed image reaches the left and right eyes through different places on the lens surface of the magnifying glass. When passing through the lens surface, the light is bent by refraction, and the amount of the bending depends on the inclination of the lens surface. Since the lens surface is a curved surface and has a different inclination depending on the location, distortion occurs in the image formed on the retina of the eye, and the force differs between the left and right eyes. As a result, it is understood that there is a difference between the images formed on the retinas of the left and right eyes, and that the effect of the “binocular parallax” of the eyes acts to give a stronger three-dimensional effect.

The difference in the shape of the images formed on the retinas of the left and right eyes does not seem to have a significant effect on the degree of appearance of the stereoscopic effect. However, up to a certain range, the greater the difference between the two images, the more the stereoscopic effect tends to appear. Also, when the difference between the two images gradually increases in a wider range, the stereoscopic effect tends to be more easily perceived than when the difference in the narrow range is repeatedly distributed.

When viewing an actual stereoscopic scene, the difference between the images that occur in the left and right eyes gradually increases over a wide range that covers the entire image, but the difference between the left and right eyes gradually increases in the binocular image due to the curved lens. It is important in the present invention that a stereoscopic effect with a sense of depth appears in the entire image of the display image even when the difference is repeatedly distributed. Even when the range of repetition is relatively small, a three-dimensional effect is exhibited.

Next, the knowledge obtained about the relationship between the direction of the change of the lens surface and the strength of the three-dimensional effect that appears will be described.

A description will be given of the appearance of a three-dimensional appearance when a lens is used in which a lens surface smoothly changes in a curve only in a certain direction and does not change in a direction orthogonal to the certain direction. . A typical lens of this type is well known as a cylindrical lens or a semi-cylindrical lens. When there is no change in the curved surface in the left and right direction of the eye, the stereoscopic effect is weak, almost the same as when viewed with one eye, and there is almost no effect seen with both eyes. A strong three-dimensional effect appears in both eyes when there is a curved change in the left and right direction of the eye, and more than when there is a curved change only in the left and right direction of the eye. When there are both changes in the surface in both directions, the three-dimensional effect appears intensified.When the changes in the surface in both the horizontal direction of the eye and the vertical direction of the eye are approximately the same, the three-dimensional effect becomes the strongest. felt.

In the above description, when there is no curved change in the horizontal direction of the eye, the appearance is almost the same as when viewed with one eye, but when a relatively large display image is viewed relatively close. The line of sight of the left and right eyes looking at the four corners of the displayed image is oblique, and the lens surface acts equivalently to the line of sight as if there is a component of a curved change in the left and right direction. As a result, a three-dimensional effect appears on the whole. In other words, a three-dimensional effect is exhibited even when there is no curved change in the lens surface in the horizontal direction of the eye.

As a matter of course, the three-dimensional effect that appears as the degree of lens curvature changes increases. At the same time, the distortion becomes stronger.

In any method that gives a three-dimensional effect, the fineness of the image has a significant effect on the three-dimensional effect. Therefore, it is important to minimize the occurrence of distortion due to curved lenses. For this reason, a smooth uneven surface is used for the lens surface.

One of the newly obtained findings is that the relationship between the direction of the change in the lens surface described above and the directions of the left and right eyes greatly affects the degree of appearance of a three-dimensional effect.

Here, when there is a curved surface change in both the left and right directions of the lens surface and the vertical direction of the eye, the stereoscopic effect is greater than when there is only a curved surface change in the left and right direction of the eye. I explain one of the interpretations of the phenomenon that appears strongly. When viewed with both eyes, the image appears to be three-dimensionally distorted as if it were deformed in the depth direction. If the deformation is only a curved change in the left and right direction of the eye, the image appears to be a deformed image as if looking straight from the front of the pattern or landscape appearing in the display image. On the other hand, if there is a curvilinear change in both the left and right direction of the eye and the up and down direction of the eye, the change is as if viewed from an oblique direction. It looks like a shaped image. In general, even in a three-dimensional landscape, a three-dimensional appearance is emphasized when viewed obliquely. Also, even with two-dimensional paintings that emphasize perspective by applying perspective, etc., paintings that are drawn from an oblique direction will give a stronger sense of stereoscopic effect than pictures that are viewed from the front. In particular, an image viewed from the upper oblique direction or the lower oblique direction emphasizes the sense of standing. If we think that the same thing is working, we can understand this phenomenon.

The above description is of the case where a cylindrical lens is used, but the same phenomenon occurs in the case of a curved lens having a single arbitrary concave surface or a single arbitrary convex surface as a lens surface. The same applies to a lens surface consisting of an arbitrary concave surface and an arbitrary convex surface.

The three-dimensional effect expressed here is based on the empirical habit of recognizing the brain as three-dimensional based on the difference between the images formed on the retinas of the left and right eyes when viewing objects arranged three-dimensionally. Therefore, it can be considered that the difference between the images formed on the retinas of the left and right eyes by the lens is determined by the brain to be three-dimensional. Therefore, it is desirable that the difference in image be the same as when looking at an actual three-dimensionally arranged object. A convex or concave surface constituting a lens surface is a curved surface with a sufficiently wide spread. Desired Les ,. Preferably, a single convex or concave surface is preferred. However, it has already been described that a three-dimensional effect is exhibited even when the period at which the concave lens and the convex lens are repeated is sufficiently smaller than one side of the display image. This is one of the newly obtained findings.

This will be described in more detail in the following embodiments.

The two-dimensional display image viewed by both eyes through these curved lenses has three-dimensional distortion.

When viewed with one eye, only vertical and horizontal distortions, that is, only two-dimensional distortions, are perceived.However, when viewed with both eyes, the position in the depth direction of the image is deformed depending on the location, resulting in a distorted three-dimensional image. felt. Unless the degree of distortion is extremely large, this three-dimensional distortion is difficult to recognize unless you look carefully and consciously.If you do not look consciously, it is recognized as a two-dimensional distortion in the vertical and horizontal directions. Often done.

In addition, the three-dimensional effect and the three-dimensional distortion, which give a sense of the anterior-posterior relationship between the drawn objects, are different in the sense perceived by the observer. Distortion is the individual thing drawn It is a transformation that changes the shape of the body, and the three-dimensional effect is a feeling of the positional relationship between the drawn objects before and after.

The image is distorted by the lens surface. The present invention provides a configuration of a lens surface that relatively strongly expresses a three-dimensional effect with respect to the distortion, and provides a display device with less distortion and excellent three-dimensional display characteristics. The embodiments of the present invention will be described in detail.

FIG. 1 is a perspective view showing a display device according to the first embodiment of the present invention. In FIG. 1, a display device includes a curved lens 10, a display image 11 depicting a design to be displayed, and a back plate 12a holding a display image 11 and arms 12b attached to four corners of the back plate 12a. Is provided. The curved lens 10 is attached to the arm 12b. The holding mechanism 12 for holding the relative positional relationship between the display image 11 and the curved lens 10 by the back plate 12a and the arm 12b is configured.

The embodiment shown in FIG. 1 is a mode in which the distance to the display image of the curved lens is sufficiently smaller than the distance to the observer, and the curved lens and the display image can be regarded as one display device. Display image 1 1 is a flat two-dimensional display image consisting of a series of patterns drawn on ordinary paper.The lengths of the arms 12b attached to the four corners of the back plate 12a are all the same, and are flat. The curved lens 10 is placed parallel to the display image 11.

The arrow shown in the figure indicates the spatial direction, and the direction directly facing the front of the planar display image that is set up vertically by the observer is the direction z, and the direction perpendicular to this direction z is The direction connecting both eyes of the observer is indicated as direction X, and the direction orthogonal to direction Z and direction X is indicated as direction y. Except in special cases, in general, an observer standing upright looks at a display image standing upright facing the observer, and hence these directions x, y, and z are referred to as the left and right directions of the eye, respectively. It is called the vertical direction of the eye and the depth direction. Usually, the left and right sides of the eye are horizontal, and the up and down directions of the eye are vertical.

Each arm 12b attached to the four corners of the back plate 12a has a mechanism for adjusting the length, and by changing the length, the distance between the curved lens 10 and the display image 11 can be changed. Can be inclined with respect to the display image 11. Furthermore, by using a flexible curved lens, the distance between the mounting positions of the curved lens 10 to the arm 12b is made longer than the distance between the arms, so that the curved lens 10 faces the display image 11 in a curved state. Can also be placed.

In the first embodiment shown in FIG. 1, the display device has been described as a display device that converts a display image into a planar two-dimensional display image drawn on paper, but a TV receiver, a monitor of a personal computer, a mobile phone, and the like are also described. A display device according to the present invention, which also includes a means for receiving a communication image or a broadcast image. The display image is a two-dimensional display image consisting of continuous symbols. In these display devices, a curved lens is placed opposite a screen, which is a display element such as a cathode ray tube or a liquid crystal, which is electronically controlled to display an image, and maintains a relative positional relationship between the display element and the curved lens. The holding mechanism 12 corresponds to a mechanism part called a housing or a frame for fixing the both. In these electronic display devices, the display image is a strictly discontinuous design in which a small image area called a pixel is arranged, and the observer cannot identify individual pixels, and as a single continuous design Looking. In the present invention, such a display image is also a two-dimensional display image having a continuous pattern.

Further, a display device such as a projector projected on a screen is also a display device according to the present invention since if a curved lens is placed in front of the screen, a mechanism for maintaining the positional relationship between the screen and the curved lens is necessarily involved.

A two-dimensional display image is an image drawn on a two-dimensional surface, and an image obtained by bending an image drawn on a plane is also a two-dimensional display image.

FIG. 2 is a perspective view of the curved lens 10 according to the first embodiment shown in FIG. 1, and FIG. 3 is an X-axis including a straight line aa ′ shown in the center of the curved lens in FIGS. 1 and 2. FIG. 3 is a cross-sectional view in which a plane parallel to the z-axis and perpendicular to the y-axis is a cut surface.

Although various embodiments will be described below, many of them have the same device configuration as the display device according to the first embodiment shown in FIG. 1 except for a curved lens. Therefore, hereinafter, when "the device configuration is the same as that of the display device of the first embodiment", the display image 11 other than the curved lens, the rear plate 12a, and the arm 12b are constituted. It is assumed that all the holding mechanisms 12 and the like have the same configuration and perform the same functions as the display device of the first embodiment. The position of the curved lens and the display screen The relationship is the same, and the attachment of the curved lens to the holding mechanism 12 is also the same. The difference lies in the curved lens itself. In the description of the cross-sectional view of the curved lens according to the embodiment, when “the cut surface described in the first embodiment” is used, a straight line a—a ′ shown in the center of the curved lens in FIG. The plane parallel to the X and z axes and perpendicular to the y axis is used as the cutting plane.

The curved lens according to the first embodiment will be described in detail with reference to FIGS.

The outer surface 20 facing the display image 11 of the curved lens 10 is a flat surface, and the opposite outer surface facing the observer is a curved surface in which a convex surface 22 and a concave surface 23 repeat each other, and is a lens surface 21. In FIG. 2, the convex surface is indicated by oblique lines, the concave surface is indicated by white, and the boundary between the convex and concave surfaces is indicated by a line. Both the convex and concave surfaces are smooth and gently changing smooth surfaces with a sufficiently wide spread, and the two surfaces are smoothly connected at the boundary between the concave and convex surfaces.

The shape and effective area of the curved lens 10 are both rectangular. There is no curved change in the direction of 45 degrees. Under this condition, the curvilinear change component of the curved surface at both locations on the lens surface has both the left-right component of the eye and the vertical component of the eye. Note that a curve change is a change in which the ratio of the change of the curved surface to the change of the place is not constant.

As is clear from the above description, the curved lens changes in a curved shape only in a certain direction, and does not change in a direction orthogonal to the certain direction or linearly changes at a constant rate even if it changes. However, a curved lens can be easily produced by passing the roller through a roller whose diameter changes smoothly in the axial direction.

In such a display device, an observer who observes the display image 11 sees the display image supported by the holding mechanism 12 through the curved lens 10.

Next, the positional relationship of the curved lens with respect to the display image will be described. First, the focal length of a curved lens will be described.

Each of the convex and concave surfaces constituting the lens surface of the curved lens is a smoothly and gently changing curved surface having a sufficiently wide spread. It has a wide enough spread so that each convex or concave area has one optical axis and one focal point. Can not be approximated by an ideal single lens. That is, it acts as a lens having distortion. If a partial area where parallel rays arriving from a sufficiently far distance are refracted by the lens surface and can be considered to converge at one point is defined as one small local lens, a curved lens can be regarded as a series of these local lenses without gaps. Hereinafter, the focal length of a curved lens or the focal length of a lens surface refers to the focal length of such a local lens, and refers to the focal length of each local lens at any part of the curved lens or the lens surface. . The focal point of the local lens is a point when the lens surface is a spherical surface. When the lens surface is a cylindrical surface, the focal point is a linear focal line parallel to the axis of the cylindrical surface. This focal line is also generally called a focal point, and here also the focal line is called a focal point. In this case, the optical axis is not a single line but a surface that is a collection of infinite straight lines, which is also called the optical axis. The focal length can be regarded as the distance from the lens surface on the optical axis to the focal point.

The displayed image is placed away from the lens surface of the curved lens and sufficiently close to the lens surface than the focal point of the local lens.

Due to the above configuration, there is a difference between the images formed on the retina of the left eye and the right eye through the curved lens, and as a result, the original two-dimensional display image looks like a stereoscopic image with a sense of depth. appear. This will be described in more detail.

Light that has exited the same point on the displayed image reaches the right eye and the left eye, which are located at different positions in the left and right directions, through different parts on the lens. The passing point of this light is a point that differs in the left-right direction of the eye. However, since the direction in which the lens surface of the curved lens changes is oblique to the display screen, the lens surface is curved both in the left-right direction of the observer's eye and in the vertical direction perpendicular to it at any location. Is changing.

The degree of refraction of the light reaching the right eye and the left eye on the lens surface differs due to the curved change of the lens surface in the left-right direction of the eye, and the respective images formed on the retinas of the left and right eyes differ. There is a difference, and the function of “binocular parallax” of the eye acts, and there is a front-back positional relationship between the individual objects drawn in the two-dimensional display image with respect to the entire image of the display image A three-dimensional impression appears. At the same time, a three-dimensional distortion occurs in the entire image of the display image viewed by the left and right eyes due to the presence of a curved change in both the left and right directions of the eye and the vertical direction perpendicular thereto.

The three-dimensional effect and the three-dimensional Distortion is foreign to the observer's sense. Distortion is a deformation that changes the shape of each drawn object, and three-dimensionality represents the positional relationship between the drawn objects before and after.

Since the curved change in the lens surface has components in both the horizontal direction of the eye and the vertical direction of the eye, an image with a deformation that looks obliquely despite the display image being viewed from the front And the three-dimensional effect is further enhanced.

The appearance of the entire display image as a three-dimensional image having a sense of depth can be more noticeable than distortion having a sense of depth. If the distortion is limited to a certain extent, the three-dimensional effect appearing in the distortion is weak, and it is buried in the three-dimensional effect that senses the positional relationship between the front and rear of the objects drawn as the entire image of the displayed image and is not felt much. Although the three-dimensional effect of the distortion itself is hard to be perceived, the distortion is recognized as it is in the horizontal and vertical directions.

In the first embodiment, there is no area on the lens surface which is only a curved change in the vertical direction. That is, since there is no curved surface that does not contribute to the appearance of a three-dimensional effect but only causes distortion, unnecessary distortion can be eliminated.

In order to obtain a stronger three-dimensional effect, it is important that the degree of refraction of the lens surface greatly changes in a curved manner with the change in the location, but at the same time, the distance between the lens surface and the displayed image becomes larger. is important. Even if the light is refracted by the lens surface, if the distance to the display image is short, the difference in the position of the display image due to the refraction becomes small. Therefore, the displayed image must be separated from the lens surface, which also requires a certain distance.

The required degree of curve change of the lens surface, the required distance between the lens surface and the displayed image, also depends on the position of the observer. The farther the observer is from the display device, the more parallel light that exits the lens surface and reaches the left and right eyes. As a result, light that exits the same point on the display image and reaches the left and right eyes passes through a location closer to the lens surface. As a result, the difference in refraction is reduced, and the difference between the images formed in the retinas of the left and right eyes is also reduced. As a result, the three-dimensional appearance is weakened. Therefore, it is necessary to increase the distance between the displayed image and the lens surface when using a curved lens whose lens surface has a strong change in curvature when the observer views from a distance compared to when viewed from a close distance. .

On the other hand, when viewed from near the display device, the angle of sight from both eyes increases. For this reason, the difference in the location where light that exits the same point on the display image and reaches both eyes passes through the lens surface becomes large. Therefore, even if the curve change of the lens surface is relatively weak, and even if the distance between the displayed image and the lens surface is relatively small, a three-dimensional effect is effectively exhibited. As is clear from the above description, by adjusting the distance between the display image and the curved lens, it is possible to adjust the degree of appearance of a three-dimensional effect due to the difference in the distance from the display device of the observer. .

In order to create a three-dimensional effect, it is essential to keep the displayed image away from the curved lens to some extent. The three-dimensional effect becomes stronger as the displayed image is further away from the curved lens, but the image distortion of the displayed image also becomes stronger. This distortion is caused by different magnifications of the local lenses of the curved lens. Here, the distortion of the lens image will be described.

For the local lens, a lens formula known as an ideal lens can be applied.

The following relationship is established between the focal length f, the distance s of the displayed image from the lens, and the distance p of the image formed by the lens from the lens.

l / s + l / p = l / f …… (1)

The magnification m of the image is given by the following equation.

m = f / (s -f) …… (2)

Note that the focal length f takes a positive value for a convex lens and a negative value for a concave lens, and the distance s from the lens to the displayed image is always a positive value, and the image distance from the lens! The value is a positive value when it is on the opposite side of the angle, and a negative value when it is on the same side.

When the magnification m is negative, the image is an erect virtual image, and when the magnification m is positive, the image is an inverted real image.

As a display device, the image must be upright, and in the case of a convex lens, the displayed image must be located closer to the lens than the focal point.

In order for the whole image of the displayed image to be an erect image, the curved lens must have a negative value of the local lens magnification m everywhere, and in the area of the convex lens, it must be located closer to the lens than the focal point. There is. Regarding the condition of the erect image, there is no particular limitation on the position of the concave lens in the case of a concave lens.

The closer the absolute value of the magnification m of the local lens is to 1, the smaller the distortion generated in the displayed image. However, in the case of a convex lens, the degree of perceived stereoscopic effect in the whole image viewed by both eyes increases as the absolute value of the magnification m of the local lens becomes larger than 1. When the absolute value of the magnification m of the local lens is smaller than 1, in the case of the zoom lens, the intensity becomes stronger. Therefore, it is important to use the camera in such a condition that distortion is not an issue and that the entire image has a three-dimensional effect.

In order to reduce the distortion, it is preferable that the magnification m is close to 11. That is, in either case of the concave surface or the convex surface, it is desirable that the display image be located at a position closer to the lens surface than the focal point and at a position closer to the lens surface than the intermediate position between the focal point and the lens surface.

When the displayed image is placed at an intermediate position between the focal point and the lens surface, the magnification becomes 12 times in the case of the convex lens. In the case of a concave lens, the magnification is 1.06 times, and in this case, it is reduced. Furthermore, if the displayed image is placed at a distance of 1Z4 of the focal length from the lens, the magnification will be 4/3 times for a convex lens and 10.8 times for a concave lens. become.

If the displayed image is less than 1Z4 of the focal length of the local lens from the lens surface at any location on the curved lens, the magnification is limited to a value closer to -1 and the image distortion of the displayed image can be limited. Limiting image distortion is essential for a display device. Although it depends on the conditions of use, this level of distortion allows the distortion to function as a display device that allows the user to feel a stereoscopic effect even when viewed from a relatively long distance.

In the curved lens 10 according to the first embodiment shown in FIGS. 1 to 3, the convex surface 22 and the concave surface 23 are arranged at substantially the same interval with respect to one side of the effective area of the curved lens, and are repeated only at most several times. . Therefore, the lens surface is smooth and smooth with a sufficiently wide spread, and a smooth and gently changing concave surface and a smooth and gently changing convex surface with a sufficiently wide spread are alternately arranged. The surface changes to It is clear from the above description that the lens surface may be a single concave surface or a single convex surface and may be a smooth and slowly changing curved surface having a sufficiently wide spread.

The curved lens according to the present invention has the function of causing light exiting the same point on the displayed image to pass through different points on the lens surface, undergo different refractions, and reach the left and right eyes. Therefore, it does not matter whether the lens surface is convex or concave, and whether the curved lens is convex or concave.

Whether the lens surface is convex or concave, the concave and convex surfaces are arranged alternately. However, when the display image 11 is viewed through the curved lens 10 with the direction of the curved change of the curved surface adjusted to the left and right directions of the eye, a three-dimensional effect appears in the visible image. In addition, it is possible to view the display image by adjusting the curved lens so that the curved change of the curved surface includes components in both the horizontal direction of the eye and the vertical direction of the eye. A feeling appears.

The fact that the shape of the curved lens or the effective area is rectangular means that the direction of the curved surface change of the lens surface should be determined by considering the consistency with the display image that is generally distributed in a rectangular shape when configuring the display device. This is practically important for positioning in relation to the horizontal direction. And does not directly contribute to the appearance of the three-dimensional effect. However, it is important from the viewpoint of distortion that the convex or concave surface constituting the lens surface should be a smooth and slowly changing curved surface having a sufficiently wide spread.

Since the curved surface has a sufficiently wide spread, it becomes a lens with distortion rather than an ideal lens through which only paraxial rays pass. Also, since the lens surface is a smooth curved surface, there is no portion where the image to be formed changes rapidly. Furthermore, since the curved surface changes gradually, the distortion generated in the image is also gradually deformed. Such a curved lens has no part where the characteristics of the lens change suddenly with the change of the place, and can be regarded as a lens that changes gradually over a relatively wide range. The deformations that occur over a relatively large area make a difference in the images produced on the retina of the left and right eyes. The three-dimensional effect is also manifested by deformation that gradually changes over the entire screen or a relatively wide area that is not due to partial distortion, so the whole with a relatively high-quality three-dimensional effect that suppresses distortion that occurs in parts of the whole image. An image is obtained.

Also, when the lens surface is a single convex surface or a single concave surface, it can be changed more gently than in the case of a curved surface where the convex surface and the concave surface repeat alternately, and the distortion is gradual for the entire image. Because of the change, in some cases, it is easy to obtain an image with a three-dimensional effect with little noticeable distortion.

The effect of the curved lens used in the first embodiment in which the concave surface and the convex surface repeat alternately is that the thickness of the lens can be reduced. As the effective area of a curved lens having only a convex surface or a concave surface increases, the thickness of the lens can be limited as the effective area increases.

However, in the case of a curved surface where the convex surface and the four surfaces repeat alternately, the repetition period increases. As a result, many partial distortions are repeated, and in some cases, this distortion may be bothersome.

Also, a lens surface in which a convex surface and a concave surface alternate alternately, and a lens surface in which an interval between one curved surface and an interval between the other curved surfaces is extremely different, has a large change in the lens surface in some portions, and is thus preferable. Clearly not.

In the above, the manifestation of the sensation of the surface of the lens, which functions to cause a difference between the images formed on the retinas of both eyes, has been described in detail, including the relationship with the distortion. These descriptions are not limited to the first embodiment, but can be similarly applied to various embodiments described below.

Next, a second embodiment will be described in detail with reference to the drawings.

The device configuration of the display device according to the second embodiment is the same as that of the display device according to the first embodiment. The difference lies in the curved lens itself.

FIG. 4 is a cross-sectional view showing a curved lens according to the display device of the second embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment. In the figure, a front view of the display device when viewed directly from the front is illustrated together with a cross-sectional view. In the front view, the viewing direction when drawing the front view is indicated by an arrow in the cross-sectional view, and in the front view, the cutting position of the cross-sectional view is indicated by lines aa.

This curved lens is a well-known Fresnel lens type lens. Focusing on the fact that the function of the lens is related to the shape of the lens surface and does not depend on the thickness of the lens, the original lens is divided into elements whose thickness is reduced by preserving the shape of the boundary surface between materials with different refractive indices. A lens of the Fresnel lens type is obtained by arranging these elements without gaps. FIG. 4 shows the cross section of the original lens by a dotted line. The lens surface 40 of the original lens and its extended lens surface 41 are collectively referred to as a generating surface.

The curved lens is rectangular, the generating surface is a cylindrical surface, and the direction of the cylindrical axis is inclined at 45 degrees to one side of the rectangular shape of the curved lens.

The original lens is divided into a plurality of elements el to e21, each element preserving the shape of the corresponding part of the lens surface 40 of the original lens and the plane 42 facing this lens surface, and the thickness The shape is reduced from the thickness. A curved lens is one in which the flat parts of these elements are arranged in one flat plane. Mother of this curved lens The curved surface is a cylindrical surface, and at the same time, the cylindrical axis is inclined with respect to one side of the curved lens. Each element has a shape cut out along this inclined cylindrical axis, and the boundary of each element is shown as an oblique line in the front view.

A lens of the Fresnel lens type performs a function equivalent to a lens having a generating surface as a lens surface. Therefore, the curved lens in the second embodiment is equivalent to a curved lens having a curved surface obtained by inclining a cylindrical surface at an angle of 45 degrees with respect to one side of the curved lens. Therefore, since the direction of the curved change on the lens surface is oblique to the display screen, the lens surface is curved in both the left-right direction of the observer's eye and the vertical direction perpendicular to this at any location. There is a change. In addition, there is no area where only a curved change in the vertical direction occurs. .

As is clear from the above description, the second embodiment operates and performs the same function as the first embodiment.

As described above, the second embodiment has been described using the Frennner lens type curved lens in which the base curved surface is a cylindrical surface and the elements cut along the cylindrical axis are arranged, but the inclination of the cylindrical axis is 45 degrees. The angle does not need to be a degree, and may be a state in which the lens is inclined at a certain angle with respect to one side of the curved lens, for example, about 30 to 60 degrees.

Further, the generating surface is not limited to the cylindrical surface, and may have a curved surface similar to the lens surface of the curved lens according to the first embodiment.

Further, both the lens surface of the curved lens in the first embodiment and the lens surface of the curved lens in the second embodiment are curved in both the left-right direction of the observer's eye and the vertical direction perpendicular thereto. It is used in such a state that it undergoes various changes, so that the image viewed with both eyes is deformed as if the displayed image is viewed from an oblique direction, giving a stronger three-dimensional effect.

The lens surfaces of the curved lenses in the first embodiment and the second embodiment have a direction in which the curve change is greatest at any point, and include the direction in which the curve change is largest. The shape of the curved lens or the plane perpendicular to the rectangle that forms the effective area should be at an angle to one side of the rectangle so that one side of the rectangular curved lens corresponds to one side of the rectangular display image. When placed, such a curved lens can be moved in both the left-right direction of the observer's eye and the vertical direction perpendicular to it. On the other hand, it can be used in a state where there is a curved change. In the above description, it is assumed that one side of the curved lens corresponds to one side of the display image, and is not parallel because the curved lens may be tilted in the depth direction with respect to the display image. This refers to the case where both the curved lens and one side of the displayed image are on a plane parallel to the depth direction.

A curved lens of the Fresnel lens type has an important meaning in the display device for stereoscopic display according to the present invention. In order to reduce the thickness of the display device in the depth direction, it is necessary to place a curved lens close to the display image, but to achieve this, the curvature of the lens surface is increased and the strength of the curved lens is increased. It is necessary, but as the curved lens becomes thicker, it becomes difficult to bring the displayed image closer to the same distance anywhere on the lens surface. In addition, the display device cannot be made thinner due to the thickness of the curved lens itself. These problems can be solved by making the curved lens a Fresnel lens type.

Next, a third embodiment will be described in detail with reference to the drawings.

The device configuration of the display device of the third embodiment is the same as that of the display device of the first embodiment. The difference lies in the curved lens itself.

FIG. 5 is a cross-sectional view illustrating a curved lens according to the display device of the third embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

It has a two-layer structure of a material 50 having a refractive index of nl and a material 51 having a refractive index of n2. The outer surface of the material 50 is a boundary surface A in contact with air, which is a smooth and gently changing curved surface in which a convex surface and a concave surface are alternately repeated. This boundary surface A is the same as the lens surface of the curved lens 10 in the first embodiment shown in FIG. Therefore, a detailed description of the boundary surface A is omitted here.

The boundary surface B between the material 50 and the material 51 is a surface in which a small convex surface having a sufficiently small area is continuous or a small concave surface is continuously arranged in a plane with respect to either the convex surface or the concave surface of the outer surface A. . The outer surface C of the material 51 is flat.

The surface that functions as a lens must be a boundary surface with a different refractive index and a curved surface. Therefore, the lens surfaces are boundary surface A and boundary surface B.

As is clear from the above description, the curved lens is smooth and gently composed of alternating concave surfaces with a sufficiently wide spread and convex surfaces with a sufficiently wide spread. A first lens surface A, which is a curved surface that changes, and a second lens surface B in which small convex surfaces having a sufficiently small area with respect to the convex surface or concave surface constituting the first lens surface are continuously arranged on a plane. Has a multilayered structure.

Each of the minute convex surfaces constituting the second lens surface acts as an independent minute lens having an optical axis. The shape of the area of the minute convex surface, which is the lens surface of the minute lens, is not particularly limited. It is required to be small enough. The shape of the curved surface may be a spherical surface, a cylindrical surface, or an arbitrary shape. Further, the present invention is not limited to the convex surface, and minute concave surfaces may be continuously arranged. As an example of the lens surface on which the micro convex lenses are arranged, a fly's eye lens or a lenticular plate is well known.

The micro-convex or micro-concave surface is a microlens, which has the function of enlarging or reducing itself, and the function of moving the image position away from the image position. That is.

Since each microlens is sufficiently small and each microlens is an independent lens having a different optical axis, the image of each microlens becomes a new pixel and constitutes the entire image of the display image. Therefore, the microlens does not have the function of enlarging or reducing the whole image, and acts only to change the position of the image. In other words, the second lens surface merely functions to change the position in the depth direction of the image without the function of scaling up, down, left and right.

On the other hand, the first lens surface is the same as the lens surface in the curved lens according to the first embodiment described above, and the function and operation of this lens surface are as already described, and the detailed description is omitted. However, the difference in the amount of refraction depending on the location of the lens surface causes a difference between the images formed on the retinas of the left and right eyes.

The whole image of the display image created by the curved lens is equivalent to viewing the image formed by the first lens surface through the second lens surface.

The image formed by the first lens surface is enlarged or reduced in partial portions in the vertical and horizontal directions, and at the same time the position in the depth direction changes. That is, there are both vertical and horizontal deformations and depth deformations.

With the second lens surface, only the position in the depth direction of the image created by the first lens surface is further greatly deformed. That is, the whole image by the curved lens is large in the depth direction. As a result of being deformed, a stronger three-dimensional effect appears. At this time, the deformation in the up, down, left, and right directions is not emphasized depending on the second lens surface, so that distortion in the up, down, left, and right directions is suppressed, and only a three-dimensional effect appears.

As is clear from the above description, the second lens surface is made to function to further deform the position of the first lens surface in the back direction of the image created by the first lens surface, and to exert a stronger three-dimensional effect. Therefore, the lens portion of the first lens surface corresponding to each micro lens of the second lens surface is the same kind of lens, that is, both corresponding lenses are both convex lenses or both concave lenses. It is desirable to enhance the function as a lens. However, it is not necessary to match both lenses in the same area in all areas.If the three-dimensional effect in a partial area increases, the stereoscopic effect of the whole image tends to increase. This can enhance the three-dimensional effect.

Also, the focal length of the microlens does not need to be constant and changes with the location unless it changes abruptly.For example, it changes to a concave lens while weakening the characteristics of a convex lens, and then changes in order to strengthen the characteristics of the concave lens sequentially. You may.

The microlens is required to be so small that the image of the microlens can be regarded as one point of the whole image of the display image.

In the above, the characteristics and functions of the required lens, including the area shape and the shape of the curved surface, of the minute convex surface and the minute concave surface, which are the minute lenses, have been described in detail.

Next, the positional relationship between the lens surface and the display image will be described.

Regarding the first lens surface, which functions to create a difference between the images formed on the retinas of the left and right eyes, the position where the display image should be placed has already been described because it is necessary to suppress distortion in the vertical and horizontal directions within a certain range. There is no effect of the second lens surface on distortion in the vertical and horizontal directions that occurs in the entire image of the display image. This has already been explained. Therefore, only the first lens surface needs to be considered for distortion in the vertical, horizontal, and lateral directions that is easily recognized by the eyes. However, a minute curved surface, that is, a minute lens has a function as a lens, and has a problem that the quality of the whole image is affected.

When the image of the microlens is enlarged, a part of the corresponding display image is enlarged and emitted as the light amount of its own area. In other words, only a part of the light in the area to which you correspond will reach your eyes. Therefore, if the magnification is large, the image seen from outside Darkens. In addition, due to a slight displacement between the display image and the curved lens due to vibration or the like, the corresponding image portion of the minute lens greatly changes, and "flickering" occurs.

When the image of a microlens is reduced, the corresponding display image portion of the microlens passes through the microlens beyond the area that should be originally represented, to the light of the corresponding portion of the adjacent microlens. Become like As the rate of reduction further increases, the light of the corresponding portion of the next minute lens will be transmitted. When the image of the minute lens is reduced in this way, the entire image is blurred. As the degree of reduction increases, the degree of blur increases.

Whether an image formed by light passing through the microlens after exiting the display image is enlarged or reduced is not determined only by the microlens, that is, the second lens surface. It is also affected by the first lens surface. Therefore, the conditions for securing the brightness of the display and for limiting the degree of blur need to be determined in relation to the focal length of the curved lens. Here, the focal length of the curved lens is a focal length in consideration of all lens surfaces including all lens surfaces included in the curved lens.

When the image formed through the micro lens is enlarged, if the magnification is reduced to 2 times or less, at least 1Z4 or more of the light amount in the corresponding area can reach the eye through the micro lens. To satisfy this condition, the distance between the displayed image and the curved lens must be shorter than the focal length of the curved lens, 1Z2.

If the image formed through the microlens is reduced, if the degree of reduction is reduced to 1Z2 or less, the light reaching the eye through the microlens will be twice as large as its own in length and its own area in area. It can be limited to four times the area of light, limiting the degree of blurring. To satisfy this condition, the distance between the displayed image and the curved lens must be shorter than the focal length of the micro lens.

In the fourth to seventh embodiments to be described below, a curved lens having a lens surface on which a minute curved surface is arranged is used, and the positional relationship between the lens surface and the display image described above is described. Regarding the lens, the description of the characteristics and functions of the required lens, including the area shape of the minute curved surface which is the lens surface and the shape of the curved surface, similarly applies. Therefore, in these embodiments, a detailed description of the minute lens and the like and a detailed description of the positional relationship between the lens surface and the display image are omitted. Next, a fourth embodiment will be described in detail with reference to the drawings.

The device configuration of the display device according to the fourth embodiment is the same as that of the display device according to the first embodiment. The difference lies in the curved lens itself.

FIG. 6 is a cross-sectional view illustrating a curved lens according to the display device of the fourth embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

The curved lens has a two-layer structure of a material 60 having a refractive index of nl and a material 61 having a refractive index of n2. The outer surface of material 60 is the boundary surface A that is in contact with the air, and is a smooth and gently changing curved surface in which a surface with a sufficiently wide spread and a convex surface with a sufficiently wide spread are alternately arranged. . This boundary surface A is the same as the lens surface of the curved lens according to the first embodiment described above, and the functional operation of this lens surface is as already described. The surfaces serve to create differences between the images formed on the retina of the left and right eyes with CDs that vary in the amount of refraction depending on the location.

The boundary surface B between the material 60 and the material 61 is a surface in which small convex surfaces having a sufficiently small area are arranged continuously along the outer surface A with respect to either the convex surface or the concave surface of the outer surface A. The boundary surface B can be regarded as having the above-mentioned minute curved surface arranged along a virtual arrangement surface V which is a curved surface similar to the outer surface A, and the virtual arrangement surface V is indicated by a dotted line in the figure. The outer surface C of the material 61 is flat.

The difference from the curved lens of the third embodiment shown in FIG. 5 is a boundary surface B in which minute convex surfaces are arranged. In the third embodiment, the minute convex surfaces are arranged in a plane, whereas in the fourth embodiment, the minute convex surfaces are arranged along a curved surface.

From the viewpoint of the characteristics of the lens, when the curvature of the curved surface of the outer surface A is relatively small, the boundary surface B is made of a lens surface M in which minute convex surfaces are arranged approximately in a plane and the material on both sides sandwiching the boundary surface. It can be considered to be composed of a lens surface N which is the same as the material on both sides of the minute convex surface and has the same boundary surface shape as the virtual array surface V. In this embodiment, the virtual arrangement surface V and the boundary surface A in contact with the air have the same curved shape, and the virtual arrangement surface V and the boundary surface A overlap at a narrow interval. In this case, the function as a lens integrating the two lens surfaces, the boundary surface A and the lens surface N, is as follows: a material 61 having a refractive index of π2 has the same curved surface as the boundary surface Α and is in direct contact with the air. Look approximately I can do it.

Even when the boundary surface A and the virtual array surface V overlap with a large gap, or when the minute convex surface is arranged on a virtual array surface having a different curved shape from the boundary surface A, the virtual array surface and the virtual array surface V As long as A is a similar surface, i.e., a force that is a smooth and slowly changing surface with a sufficiently wide spread on either side, either a single concave surface or a single convex surface The lens surface N and the boundary surface A are combined as long as it is a smooth and slowly changing curved surface consisting of a concave surface with a wide spread and a convex surface with a sufficiently wide spread alternately arranged. The equivalent lens surface of the lens is a smooth, slowly changing curved surface with a wide enough spread of either a single concave or a single convex or a sufficiently wide spread And convex surfaces having a sufficiently wide spread concave having the smooth formed by alternately arranged, and slowly changing the boundary surface is either a curved lens surface P and regarded it as possible.

As is clear from the above description, here, the virtual lens surface P obtained by combining the boundary surface A and the virtual lens surface N is set as the first lens surface, and the virtual lens surface M is set as the second lens surface. It can be easily understood that the function and the function of the curved lens in the third embodiment are the same as those of the third embodiment.

This embodiment is an example in which minute convex surfaces are arranged, but minute convex surfaces may be used.

Next, a fifth embodiment will be described in detail with reference to the drawings.

The device configuration of the display device according to the fifth embodiment is the same as that of the display device according to the first embodiment. The difference lies in the curved lens itself.

FIG. 7 is a cross-sectional view illustrating a curved lens according to the display device of the fifth embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

The curved lens is made of a material 70 with a refractive index of nl, and the boundary surface A, which is one of the outer surfaces, is a smooth surface consisting of a concave surface with a sufficiently wide spread and a convex surface with a sufficiently wide spread alternately arranged. In addition, the curved surface is formed by arranging a small convex surface having an area extremely small with respect to the area of the convex surface or the concave surface of the virtual array surface V along the virtual array surface V that gradually changes. In the figure, the virtual array plane V is indicated by a dotted line, and this virtual array plane V is the same as the lens surface of the curved lens 10 in the first embodiment shown in FIG. The remaining outer surface B is flat.

From the viewpoint of the lens, since the virtual array surface V changes slowly, the boundary surface A is a virtual lens surface N having the same shape as the virtual array surface V and a virtual lens in which minute convex surfaces are arrayed in a plane. It can be approximated that the surface M overlaps two layers.

Here, if the virtual lens surface N is regarded as the first lens surface and the virtual lens surface M is regarded as the second lens surface, the operation is the same as in the case of the third or fourth embodiment. It is easy to understand that it works.

The curved lens according to the fifth embodiment functions as two lens surfaces as a first lens surface and a second lens surface having different properties at one boundary surface A which is an outer surface. I have.

In this embodiment, the minute convex surface is arranged, but a minute concave surface may be used.

Next, a sixth embodiment will be described in detail with reference to the drawings.

The device configuration of the display device according to the sixth embodiment is the same as that of the display device according to the first embodiment. The difference lies in the curved lens itself.

FIG. 8 is a cross-sectional view illustrating a curved lens according to the display device of the sixth embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

Two layers of thin materials 82 and 83 with refractive indices of n2 and n3 were sandwiched between thin film materials 81 and 84 with constant refractive indices of nl and n4, respectively. It has a layer structure of layers. Material 81 smoothly repeats the irregularities, and its outer surface A and the boundary surface B between material 81 and material 82 are smooth surfaces in which concave and concave surfaces alternate alternately. The boundary surface C between the material 82 and the material 83 is a small convex surface whose area is small enough for both the convex surface and the concave surface of the outer surface Α and the boundary surface Β along the virtual array surface V of the same curved surface as the boundary surface B. It is an arrayed surface. Note that the virtual array plane V is indicated by a dotted line. The boundary surface D between the material 83 and the material 84 and the outer surface E of the material 84 are flat.

Further, the outer surface A and the boundary surface B have the same curved surface as the lens surface of the curved lens 10 in the first embodiment shown in FIG.

The surface that functions as a lens must be a boundary surface with a different refractive index and a curved surface. Therefore, the lens surfaces are boundary surfaces A and B, Surface C.

Since the outer surface A and the boundary surface B are curved surfaces having the same shape and the interval between them is narrow, as described in the fourth embodiment, it is assumed that the material having the refractive index n2 is in direct contact with air with the same curved surface. Lens surface. If this virtual lens surface is regarded as the first lens surface and the boundary surface C is regarded as the second lens surface, it can be easily understood that the function and the function are the same as in the case of the fourth embodiment.

Further, in this embodiment, an example in which lens surfaces having the same shape are overlapped at a small interval has been described. However, even when the interval is large, it can be approximately regarded as a single lens surface. Even in different cases, it can be regarded as an approximate virtual single lens surface.

In addition, when a curved surface on which minute curved surfaces are arranged overlaps in multiple layers, it can be similarly regarded as a virtual single lens surface.

Therefore, even in the case of a curved lens having a multi-layered lens surface, these can be integrated as necessary and regarded as one equivalent lens surface. Therefore, in the third to sixth embodiments or the seventh to eleventh embodiments to be described below, each lens surface is described as being single, but similar curved surfaces are stacked in multiple layers. It is clear that even in the case where it exists, since it can be integrated into the equivalent lens surface, the function and function described so far can be exhibited.

Also, in the embodiments described so far and in the embodiments described below, one of the outer surfaces is a plane, but it is clear that these may be curved surfaces and used as lens surfaces.

Next, a seventh embodiment will be described in detail with reference to the drawings.

The device configuration of the display device of the seventh embodiment is the same as that of the display device of the first embodiment. The difference lies in the curved lens itself.

FIG. 9 is a cross-sectional view illustrating a curved lens according to the display device of the seventh embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

The curved lens is composed of a material 91 with a refractive index of nl and a material 92 with a refractive index of n2. The outer surface A of the material 91 is the same as the lens surface in the second embodiment. That is, it has a lens surface of the Fresnel lens type. The boundary surface B between the material 91 and the material 92 is a Fresnel lens type lens surface, and a small convex surface with a sufficiently small area is arranged in a plane in both the convex surface and the concave surface of the outer curved surface of the outer surface A. Face. The outer surface C of the material 92 is flat.

The curved lens is rectangular, and the generating curve of the outer surface A is a cylindrical surface like the lens surface in the second embodiment, and the direction of the cylindrical axis is inclined at 45 degrees to one side of the rectangular of the curved lens. It is oblique and has a component that changes both in the horizontal direction of the eye and in the vertical direction of the eye in the curved change component of the curved surface at any position on the lens surface. Boundary surface B has the same curved surface as the second lens surface in the third embodiment shown in FIG. Therefore, the outer surface A can be regarded as the one obtained by replacing the first lens surface of the third embodiment with a cylindrical surface.

Therefore, it can be easily understood that the seventh embodiment operates and functions in the same manner as the third embodiment.

In this embodiment, the minute convex surface is arranged, but a minute concave surface may be used. In the third to seventh embodiments described above, the lens surface for causing a difference between the retinal images of the left and right eyes of the curved surface lens, or the mother curved surface in the Fresnel lens type lens surface, Although a specific curved surface has been described, these curved surfaces are either a single concave surface or a single convex surface, or a smoothly changing surface, or a smooth surface formed by alternately arranging concave and convex surfaces. It is clear that any one of the curved surfaces that changes in the shape may be used.

Needless to say, like the lens surfaces in the first and second embodiments, both the left-right component of the eye and the upper-lower component of the eye are included in the curved change component of the curved surface at any position on the lens surface. It is preferable that the curved surface has a three-dimensional appearance. However, since the effect of the second lens surface enhances the three-dimensional effect, it is not always necessary to limit to such a special curved surface. .

Further, the second lens surface in the third to seventh embodiments is a curved surface in which a convex surface is a minute curved surface having a sufficiently small convex surface, or a concave surface is a curved surface in which sufficiently small minute curved surfaces are arranged in contact with each other. The surface changes suddenly at the boundary of the minute surface that touches each other. are doing.

In the eighth to eleventh embodiments described below, the second lens surface is different from the third to seventh embodiments, and the second lens surface is similar to the first lens surface. It is a smooth curved surface in which convex and concave surfaces are alternately arranged. Therefore, the function and effect of the second lens surface are different.

Next, an eighth embodiment will be described in detail with reference to the drawings.

The configuration of the display device according to the eighth embodiment is the same as that of the display device according to the first embodiment. The difference lies in the curved lens itself.

FIG. 10 is a sectional view showing a curved lens according to the display device of the eighth embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

This curved lens is made of a material: 100, and a boundary surface B in contact with air and a boundary surface B in contact with air constitute a lens surface. It has a structure in which the boundary surface A is the first lens surface and the boundary surface B is the second lens surface, and both lens surfaces are multilayered.

Boundary surface A is a smooth and gently changing curved surface in which the cylindrical axis is a straight line perpendicular to the plane of the paper, and the concave surface whose cylindrical axis is a straight line perpendicular to the plane of the paper is alternately repeated.

The boundary surface Β is a smooth curved surface in which convex and concave cylindrical surfaces having an area small enough for both the convex surface and the concave surface of the outer surface Α are alternately repeated. Both the convex surface and the cylindrical axis of the £! Surface forming the boundary surface B are straight lines perpendicular to the paper surface.

In both the first lens surface and the second lens surface, the cylindrical axis of the cylindrical surface that forms the lens surface is perpendicular to the paper surface, and the lens surface changes in a curved manner in the horizontal direction of the left and right eyes . Therefore, the difference in the amount of refraction depending on the location of the lens surface causes a difference between the images formed on the retinas of the left and right eyes.

Each convex or concave surface constituting the lens surface causes a difference between the images of both eyes with respect to the corresponding display image region according to the area. In addition, the image distortion occurs in units of a size corresponding to the area of each convex or concave surface.

On the first lens surface, the difference that occurs between the images of both eyes is in a relatively large range. In addition, distortion generated in an image is a unit in a relatively large range. On the other hand, on the second lens surface, both the difference between the images of both eyes and the distortion generated in the images are relatively small. These are repeated for each range.

Since the convex and concave surfaces of the first lens surface and the small convex and concave surfaces of the second lens surface are different in size, the difference between the images produced on the left and right eyes is large on the first lens surface. It occurs with a large repetition period in units of area, and occurs on the second lens surface with a short repetition period in units of small regions. These coexist and interact with each other to produce a stronger three-dimensional effect than when each is alone. Since the distortion caused by the first lens surface and the second lens surface is also a repetition of a large distortion range and a repetition of a small distortion range, the degree of distortion enhancement is small. In other words, the distortion is suppressed and a sense of standing is strongly exhibited. Note that the convex surface and the concave surface of the second lens surface are relatively smaller than the convex surface or the concave surface of the first lens surface. Therefore, curved surfaces such as a convex surface and a concave surface in the second lens surface are referred to as a small convex surface and a small concave surface as necessary.

Next, a ninth embodiment will be described in detail with reference to the drawings.

The device configuration of the display device according to the ninth embodiment is the same as that of the display device according to the first embodiment. The difference lies in the curved lens itself.

FIG. 11 is a sectional view showing a curved lens according to the display device of the ninth embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

The curved lens is made of a material 110 having a refractive index of nl, and a boundary surface A, which is one of the outer surfaces, is virtual along a virtual array surface V which is the same curved surface as the boundary surface A of the eighth embodiment. The arrangement surface is a smooth curved surface in which small surfaces and small concave surfaces having an area smaller than the area of the convex surface or the concave surface constituting the array V are alternately arranged. The virtual arrangement plane V is shown by a dotted line in the figure. The remaining outer surface Β is a plane.

If an area range equivalent to each convex or concave surface constituting the virtual array surface is taken into account, the boundary surface 仮想 is a virtual lens having approximately the same shape and the same position as the virtual array surface V. Surface N can be considered. On the other hand, if a small concave surface or a small convex surface having a relatively small area arranged on the virtual array surface is to be considered, the boundary surface A is approximately equal to the small area arranged on the virtual array surface. It can be regarded as a virtual lens surface M in which convex surfaces and small concave surfaces are alternately arranged in a plane. Therefore, the boundary surface A can be considered as a multilayer structure of the virtual lens surface M and the virtual lens surface N. Here, assuming again that the virtual lens surface N is the first lens surface and the virtual lens surface M is the second lens surface, the first lens surface is the same as the first lens surface of the eighth embodiment. Similarly, the second lens surface is a smooth curved surface in which small convex surfaces and small four surfaces each having an area smaller than the area of each convex surface or the ia surface constituting the first lens surface are alternately arranged.

Therefore, on the first lens surface, the difference that occurs between the images of both eyes is based on a relatively large unit. In addition, a range in which a distortion generated in an image is relatively large is a unit. On the other hand, on the second lens surface, both the difference occurring between the images of both eyes and the distortion occurring in the image are repeated in units of a relatively small range.

As is clear from the above description, the curved lens according to the ninth embodiment functions in the same manner as the curved lens according to the eighth embodiment, and is formed by the first lens surface and the second lens surface. The differences in the eye images interact with each other, resulting in a stronger stereoscopic effect than each alone. For the distortion caused by the first lens surface and the second lens surface, the extent of the distortion is small because the area ranges are different. That is, distortion is suppressed and a three-dimensional effect is strongly exhibited.

Furthermore, it is also possible to regard the boundary surface A of this embodiment as a new virtual array surface, and alternately arrange small convex surfaces and small concave surfaces having a smaller area on this virtual array surface.

In other words, the lens surface in this case is a virtual lens surface Z in which small convex surfaces and small concave surfaces having a smaller area are alternately arranged in a plane on the virtual lens surface M and the virtual lens surface N described above. Can be regarded as having multiple layers.

Next, a tenth embodiment will be described in detail with reference to the drawings.

The device configuration of the display device of the tenth embodiment is the same as that of the display device of the first embodiment. The difference lies in the curved lens itself.

FIG. 12 is a sectional view showing a curved lens according to the display device of the tenth embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

The curved lens has a two-layer structure of a material 120 having a refractive index of nl and a material 121 having a refractive index of n2. The outer surface of the material 120 is the boundary surface A in contact with air, which is the same as the outer surface A in contact with air in the curved lens according to the eighth embodiment described above. The boundary surface B between the material 1 20 and the material 121 corresponds to the outer surface A along the virtual arrangement plane V indicated by the dotted line in the figure. The convex and concave cylindrical surfaces, whose areas are sufficiently smaller than the convex or concave surfaces, are smooth curved surfaces that alternate alternately. The virtual array plane V is a curved surface having the same shape as the outer surface A, and is located near the outer surface A along the outer surface A. The outer surface C of the material 121 is flat. · As can be easily understood from the description of the ninth embodiment, the boundary surface B is approximately the same shape as the virtual array surface V and is arranged on the virtual lens surface N and the virtual array surface V at the same position. It can be considered that the virtual lens surface M in which the small convex surface and the small concave surface are alternately arranged in a plane is overlapped in multiple layers.

The virtual lens surface N and the boundary surface A have the same curved surface shape.Here, the virtual lens surface P obtained by combining the lens surface of the boundary surface A and the virtual lens surface N in multiple layers The first lens surface can be regarded as the virtual lens surface M, and the virtual lens surface M can be regarded as the second lens surface.

As is clear from the above description, the curved lens in the tenth embodiment functions in the same manner as the curved lens in the eighth embodiment or the ninth embodiment. The difference between the binocular images generated between the lens surfaces of the lenses interacts with each other, and a stronger stereoscopic effect appears than when each of them is used alone. As for the strain, the distortion caused by the first lens surface and the second lens surface has a different area range, so that the degree of the distortion being emphasized is small. That is, distortion is suppressed and a three-dimensional effect is strongly exhibited.

Next, an eleventh embodiment will be described in detail with reference to the drawings.

The device configuration of the display device of the first embodiment is the same as that of the display device of the first embodiment. The difference lies in the curved lens itself.

FIG. 13 is a cross-sectional view illustrating a curved lens according to the display device of the eleventh embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

The curved lens has a two-layer structure composed of a material 131 having a refractive index of nl and a material 132 having a refractive index of n2, and the outer surface A of the material 131 is a Fresnel lens type lens surface, and the base curved surface is an eighth surface. This is the same curved surface as the boundary surface A which is the outer surface in the embodiment.

The boundary surface B between the material 131 and the material 132 is a smooth curved surface in which a convex cylindrical surface and a concave cylindrical surface are alternately repeated. The convex cylindrical surface and the concave cylindrical surface have a smaller area than either the convex surface or the concave surface of the generating surface of the outer surface A. Therefore, the convex cylindrical surface is small. The convex and concave cylindrical surface is a small concave surface. This boundary surface B functions as a lens surface similar to the boundary surface B which is the outer surface in the eighth embodiment. The outer surface C of the material 132 is flat.

Since the lens of the Fresnel lens type functions as a lens having a generating surface as a lens surface, the boundary surfaces A and B are regarded as the first lens surface and the second lens surface in the eighth embodiment, respectively. And functions in the same manner as in the eighth embodiment, such as operation and effects.

There are two differences between the eighth embodiment and the eleventh embodiment.The first is whether or not the first lens surface is a Fresnel lens type, and the second is the second. The difference is whether lens surface 1 is a boundary surface in contact with air or a boundary surface between two materials other than gas. The effect of making the lens a Fresnel lens form is to make the lens thinner.

The effect of using the interface between the two materials as the lens surface is that the degree of freedom in selecting the refractive index increases and the degree of freedom in controlling the focal length of the lens increases. Note that the lens surfaces of the curved lenses in the embodiments described so far and in the embodiments to be described below may be interfaces that are all in contact with air or interfaces of two materials other than gas. What is necessary is just to select according to a required focal length.

As is clear from the above description, in the eighth to eleventh embodiments, the lens surface of the first lens surface or its generating surface is a cylindrical surface, and the cylindrical axis is perpendicular to the paper. Although it is a straight curved surface, it is not limited to such a curved surface, and either a single concave surface or a single convex surface is a smooth curved surface, or a concave surface and a ώ surface are alternately arranged Obviously, a smooth curved surface is good. Needless to say, like the lens surfaces in the first and second embodiments, the curved change component of the curved surface has both the horizontal component of the eye and the vertical component of the eye at any location on the lens surface. A curved surface is preferable because it gives a stronger three-dimensional effect. However, since the effect of the second lens surface enhances the three-dimensional effect, there is little need to limit the use to such a special curved surface.

Also, the second lens surface of each of the eighth to eleventh embodiments also includes small concave surfaces and small convex surfaces which are sufficiently smaller than the area of the concave or convex surface constituting the first lens surface, and are alternately arranged. Special for concave or convex shapes that are good for smooth curved surfaces It is clear that there are no restrictions.

However, if the convex or concave surface of the first lens surface or the second lens surface is systematically and regularly arranged, the distortion becomes conspicuous, and from the viewpoint of making the distortion less conspicuous, the convex or concave surface has various shapes. It is advisable to use as regular as possible.

Here, a description will be additionally given of a smooth curved surface in which concave surfaces and convex surfaces are alternately arranged. Basically, the concave surface and the convex surface are in direct contact with each other.However, even if a plane enters the boundary between the concave surface and the convex surface, the concave surface and the 的に surface are equivalently directly Obviously, the present invention is a curved surface in which concave and convex surfaces are alternately arranged even when the boundary portion includes such a narrow plane. What is important is that these convex, round, or narrow planes smoothly contact to form a curved surface.

Further, a description will be given of the lens surface of the Fresnel lens type. In the second, seventh, and eleventh embodiments, the lens surface is of the Fresnel lens type. However, the boundary surface between the third and fourth embodiments, and the virtual array surface of the fifth embodiment V, boundary planes in the sixth embodiment Α and Β, virtual arrangement plane V, and boundary plane in the eighth embodiment Α, virtual arrangement plane V in the ninth embodiment, tenth embodiment It can be easily understood that the curved surface of the boundary plane Α and the virtual array plane V in can be a Fresnel lens type curved surface.

In the third to eleventh embodiments, each lens surface of the first lens surface and the second lens surface is a lens surface having a single boundary surface except for a part. It is also easily understood that a lens surface composed of a plurality of boundary surfaces in which the boundary surfaces are stacked in multiple layers may be used.

In the third to eleventh embodiments described so far, a curved lens having two types of lens surfaces, a first lens surface and a second lens surface, is used. Next, a display device using a curved surface composed of one kind of lens surface will be described in detail as a twelfth embodiment with reference to the drawings.

The device configuration of the display device of the twelfth embodiment is the same as that of the display device of the first embodiment. The difference lies in the curved lens itself. FIG. 14 is a sectional view showing a curved lens according to the display device of the twelfth embodiment. The cross section of the cross section is the same as the cross section described in the first embodiment.

This curved lens is made of material 140, and the boundary surface A in contact with air is the lens surface, and the boundary surface B in contact with air is also a flat surface.

The boundary surface A, which is a lens surface, is a smooth curved surface in which convex and concave cylindrical surfaces having an area small enough for the effective area are alternately repeated. The cylindrical axes of the small convex surface and the small concave surface constituting the boundary surface A are both straight lines perpendicular to the paper surface.

The cylindrical axis of the cylindrical surface constituting the lens surface is perpendicular to the paper surface, and the lens surface changes in a curved manner in the horizontal direction of the left and right eyes. Therefore, the difference between the amounts of refraction depending on the location of the lens surface causes a difference between the images formed on the retinas of the left and right eyes. The difference between the images of both eyes occurs in units corresponding to the convex and concave surfaces constituting the lens surface, and these unit regions are repeated. In this way, even when the regions with the difference between the binocular images are distributed in the whole image, a solid feeling with a sense of depth appears in the whole image. Also, as for the distortion, a distortion having a size corresponding to the small convex surface and the small concave surface is distributed, so that the distortion can be set to a size that does not seem to hinder the whole image. In addition, since the lens surface is a smooth curved surface, there is no sharply changing distortion, and the displayed image can be viewed as a three-dimensional image while maintaining the image quality at a certain level.

In this embodiment, the lens surface is a cylindrical surface, and the cylindrical axis is a curved surface having a straight line perpendicular to the paper surface. However, the present invention is not limited to such a curved surface, and is a smooth curved surface as in the other embodiments. It is clear that there are no particular restrictions on the shape of the concave or convex surface other than the above.

The various curved lenses according to the present invention have been described in detail in the first to twelfth embodiments. Next, a thirteenth embodiment in which the present invention is applied to a mobile phone will be described in detail with reference to FIG.

FIG. 15 is a cross-sectional view of the mobile phone in use in a cross-section orthogonal to the left-right direction of the eye. This cross-sectional view shows the main parts of the cross-sectional views at multiple cut planes parallel to each other in order to clarify the configuration that is not a single cut plane.

The mobile phone shown in the figure consists of two frames, A frame 151 and B frame 152. And act as lids to protect each other. These frames have an opening / closing mechanism 153 that closes when not in use and opens when in use.

A display element 154 such as a liquid crystal is mounted on the A frame 151 so that the user can face the user's face with the frame opened.

A dial button 155 and the like are mounted on the B frame 152.

A curved lens 156 is placed facing the display element 154. The curved lens 156 is the curved lens described in the first to eleventh embodiments. The curved lens 1 56 is connected to an opening and closing mechanism by a lens support 157. The curved lens 156 is in contact with a flip-up mechanism 158 which is a thin plate-like panel.

When the mobile phone is not used, the opening / closing mechanism 153 rotates, the A frame and the B frame approach each other, sandwiching the curved lens 156, and the whole mobile phone becomes compact. The positions of the curved lens 156 and the flip-up mechanism 158 with respect to the A frame in this state are indicated by dotted lines.

When the mobile phone is used, the opening / closing mechanism 153 rotates and the B frame moves away from the A frame, so the restraint of the curved lens 156 is released, the flip-up mechanism 158 returns to its original shape, and the curved lens 156 is Move to a position away from the display element.

As a result, the curved lens is separated from the display image by an appropriate distance in the use state, and the display image on the display element can be viewed as a three-dimensional image. On the other hand, when not in use, the mobile phone can be placed in a position close to the display element to make the mobile phone compact and portable.

The fact that it is important that the curved lens is separated from the display image by an appropriate distance in order to produce a three-dimensional effect has already been described in the first embodiment, and a detailed description thereof will be omitted.

Next, a fourteenth embodiment in which the present invention is applied to a mobile phone as in the thirteenth embodiment will be described in detail with reference to FIG.

FIG. 16 is a cross-sectional view of a mobile phone in use in a cross section orthogonal to the left and right directions of the eye. This cross-sectional view shows the main parts of the cross-sectional views at multiple cut planes parallel to each other in order to clarify the configuration that is not a single cut plane.

The fourteenth embodiment uses a flexible curved lens 201 and a curved lens. This is the same as the thirteenth embodiment except that the supporting method is different. That is, an A frame 151, a B frame 152, an opening / closing mechanism 153, a display element 154, a dial button 155, and a flip-up mechanism 158 are provided.

In the flexible curved lens 201, one end of the curved lens 201 indicated by g in the figure is fixed to the A frame, and the other end indicated by h is connected to a moving mechanism that can move along the surface of the A frame. In this state, it is placed facing display element 154. The moving mechanism is omitted in the figure. The curved lens 201 is in contact with a flip-up mechanism 158 which is a thin plate-like panel.

When the mobile phone is not used, the A frame and the B frame come close to each other and sandwich the curved lens 201, so that the entire mobile phone becomes compact. The positions of the curved lens 201 and the flip-up mechanism 158 in this state with respect to the A frame are indicated by dotted lines.

When the mobile phone is used, since the B frame is separated from the A frame, the restraint of the curved lens 201 is released, and the flip-up mechanism 158 returns to its original shape. As a result, the curved lens 201 attempts to move away from the display element, but one end g of the curved lens 201 is fixed to the A frame, and the other end h is connected to a moving mechanism that moves along the A frame. Since both ends cannot change the distance from the A frame, the curved lens rises in a curved shape. As a result, the curved lens is not only moved away from the display image, but also curved.

The effect of the curved lens moving away from the display image when in use and the compact shape that is easy to carry when not in use are the same as in the thirteenth embodiment. However, the curved lens is significantly different from the thirteenth embodiment. The curvature of the curved lens has a large effect on the appearance of a three-dimensional effect.

In the stereoscopic display according to the present invention, the lens surfaces of the curved lenses play an important role in producing a difference between the images formed on the retinas of the left and right eyes. To enhance this function, the curvature of the lens surface must be increased. This curvature can be controlled by the degree of curvature. However, with respect to the appearance of a three-dimensional effect, the effect of the inclination of the lens is greater than the effect of the change in curvature due to the curvature. The curvature causes the lens portion to be inclined with respect to the eye. The degree of the inclination varies depending on the place where the inclination is not uniform. When this lens is tilted with respect to the eye, the function as a lens is strengthened, and it acts as if the focal length was shortened equivalently. You.

The degree to which the lens is tilted due to the curvature is small at the part directly facing the eye, and increases as the distance from the part approaches the end. Therefore, if the center of the display image corresponds to the center of the curve and the end of the display image corresponds to the end of the curve, the increase in distortion is suppressed at the center of the display image being viewed, and Therefore, as the distortion increases, the difference between the images seen by the left and right eyes also increases.

The perceived three-dimensional effect does not need to be different for the whole image. Even if the difference is small at the center and becomes larger as approaching the edge, the larger the difference itself, the stronger the three-dimensional effect is expressed. In addition, the distortion that is perceived is stronger when it is closer to the center of the gaze target, and is weaker when it is closer to the edge. Therefore, the curvature suppresses an increase in the distortion of the central portion to be watched, and the stereoscopic effect is more strongly developed. This is the effect of Curvature :!

When viewed obliquely with a flat curved lens, the curved lens faces the observer obliquely. As a result, the characteristics of the curved lens are equivalently enhanced, and the distortion is enhanced over the entire surface, so that the viewing zone is relatively narrow. When the curved lens is curved, the observer in a wide area can face the observer under similar conditions, and the viewing area can be expanded. This is the second effect.

In the fourteenth embodiment, the upper and lower sides are curved. Even in this case, which is not in the horizontal direction, in areas where the line of sight falls obliquely upward or downward, the angle of inclination is strong relative to the line of sight, and the difference between the images formed by the left and right eyes increases, resulting in a stereoscopic effect. Strengthens. In other words, the three-dimensional effect is strongly felt in any direction. In particular, when viewing from a relatively close position, the distance between the eyes works effectively to enhance the stereoscopic effect.

Further, the curvature is not limited to only the concave surface or only the convex surface, and may be such that the non-concave surface and the convex surface are alternately repeated.

The effect of the curvature of the curved lens described in the fourteenth embodiment can be applied not only to a mobile phone but also to a portable information device such as a palmtop or a laptop, or any device including any display element. Of course, in the display devices of the first to twelfth embodiments, the same effect can be obtained by bending the curved lens. The curvature of the curved lens described above is a state in which each lens surface constituting the curved lens is bent along the curved surface, and the area of the concave or convex surface constituting each lens surface is larger than the area of the curved arm surface. In this case, it can be considered that the M surface or convex surface that constitutes each lens surface is approximately equivalent to the arrangement of the convex surface along the curved arm surface. Of course, if the lens surface is bent along the virtual curved surface in advance, it is necessary to consider it as a lens surface bent along a more complicated virtual curved surface.In the thirteenth and fourteenth embodiments, Although the curved lens moves and separates from the display element when the lid is used, it is not necessary to move the lens with the lid open. It may be close. If such measures can be taken, distortion that occurs in the displayed image can be reduced when reading characters or when reading the displayed image with another device and performing authentication. As described above, the present invention has the following effects.

In the invention of the curved lens according to claim 1, a rectangular curved lens is opposed to a generally continuous two-dimensional display image of a continuous pattern of rectangles such that each side corresponds to each other. When installed and viewed through this curved lens, the following effects of the curved lens appear on the displayed image.

Since different images are formed between the right and left eyes after being deformed by the curved lens, the two-dimensional display image looks like a three-dimensional image with a sense of depth. Furthermore, this image appears to be deformed in an oblique direction, and the three-dimensional effect that appears when compared to the case where the deformation occurs only in the horizontal direction or only in the vertical direction is felt more strongly.

According to the invention described in claim 2, when the two-dimensional display image is viewed through the curved lens, the following effects of the curved lens appear on the image of the display image.

The lens surface has the same shape as the virtual array surface and the virtual lens surface at the same position, and the virtual lens surface where the small concave surface and the small convex surface arranged along the virtual array surface are arranged in a plane. Can be considered to be synthesized. Therefore, the image of the display image viewed through the curved lens placed opposite to the two-dimensional display image is a virtual lens surface. Distorted and deformed by the virtual lens surface M. The degree of this deformation varies depending on where the light that reaches the eye passes through the lens surface, resulting in a difference between the images formed in the retina of the right eye and the left eye. As a result, the two-dimensional display image appears as a three-dimensional image with a sense of depth.

In addition, since the virtual lens surface N and the virtual lens surface M have different repetition intervals of the concave surface and the convex surface, the images seen through all of these lens surfaces include the distance between the right eye and the left eye. Thus, there is a difference in which the difference gradually changes over a relatively wide range, and a difference which is repeated in a narrow range in which the difference changes in a relatively narrow range. As a result, a three-dimensional effect is felt both in the image part having a large area and in the image part having a small area, and the two parts are mutually strengthened to obtain a stronger three-dimensional effect.

The image distortion caused by the virtual lens surface N and the virtual lens surface M has different repetition periods. Therefore, it is possible to avoid that the image distortions caused by the virtual lens surface N and the virtual lens surface M reinforce each other.

Further, since the lens surface is a smooth curved surface, the deformation of the image is a smooth deformation, and is not accompanied by a sudden deformation, so that the image quality can be maintained at a certain level. According to the third aspect of the present invention, the small concave surface and the small convex surface constituting the lens surface are both at substantially the same interval, and the change of the curved surface between the small 囬 surface and the small convex surface is substantially the same. Therefore, distortion is not leveled and strong distortion does not occur in some parts. Also, the lens surface is a smooth curved surface, which can maintain a certain level of image quality.

According to the invention set forth in claim 4, the small convex surface and the small concave surface correspond to the area of the convex surface or the concave surface constituting the virtual array surface with respect to the area of each region of the convex surface or the concave surface constituting the virtual array surface. Since the area of the portion overlapping with each region is small, the difference between the repetition intervals of the concavities and convexities is large. Therefore, it is possible to avoid that both distortions affect each other and the overall image distortion strengthens each other.

In addition, the difference between the images generated between the eyes is relatively narrow and the change is relatively narrow. A change occurs in which the change of the range is repeated periodically, and the corresponding three-dimensional effect is felt for the image part having a large area and the image part having a small area corresponding to the change. And a stronger three-dimensional effect can be obtained.

According to the invention described in claim 5, when the two-dimensional display image is viewed through the curved lens, the following effects of the curved lens appear in the image of the display image.

The lens surface has the same shape as the virtual array surface and the virtual lens surface N at the same position and the virtual lens surface M where the minute convex surface or minute concave surface arranged on the virtual array surface is arranged in a plane. Can be regarded as being done. Therefore, the image of the two-dimensional display image viewed through the curved lens is first deformed by the virtual lens surface N to be different images for the right eye and the left eye, and the two-dimensional display image is three-dimensional with a sense of depth. It looks like an image.

In addition, the deformation of an image viewed as a three-dimensional image due to the virtual lens surface N is a smooth and gentle deformation, and is not accompanied by a sudden deformation, so that the image quality can be maintained at a certain level.

The virtual lens surface M functions to further change only the position of the entire image in the depth direction by the virtual lens surface N, and the 'three-dimensional appearance' further increases.

According to the invention described in claim 6, since the image of the minute convex surface or the minute concave surface can be regarded as a pixel of the whole image, the resolution of the whole image can be improved.

According to the invention described in claim 7, when the two-dimensional display image is viewed through the curved lens, the following effects of the curved lens appear on the image of the display image.

The image is distorted by both the first lens surface and the second lens surface, and the image is distorted. For this reason, a difference occurs between the images formed in the retinas of the right eye and the left eye. As a result, the two-dimensional display image looks like a three-dimensional image with a sense of depth.

In addition, the difference between the images between the two eyes changes over a relatively wide range in the portion corresponding to the first lens surface, and the difference in the image between the two eyes changes in the portion corresponding to the second lens surface. The difference varies with a relatively narrow range as a cycle. As a result, a three-dimensional effect can be felt both for an image portion having a large area and an image portion having a small area, and a stronger three-dimensional effect can be obtained by mutually strengthening the two.

Between the first lens surface and the second lens surface, the range of image distortion due to each lens surface is limited. As a result, it is possible to avoid increasing the distortion of the image.

As a result, it is possible to suppress the distortion of the image and further enhance the appearance of the three-dimensional effect. ·

Also, since the lens surface is a smooth curved surface, the deformation of the image becomes a smooth deformation without any sudden deformation, so that the quality as an image can be maintained at a certain level.

According to the invention set forth in claim 8, the small concave surface and the small convex surface constituting the lens surface are both at substantially the same interval, and the state of the curved surface change between the small concave surface and the small convex surface is substantially the same. There is no possibility that strong distortion will occur in some parts due to leveling of distortion. Also, the lens surface is a smooth curved surface, which can maintain a certain level of image quality. According to the invention described in claim 9, the small convex surface and the small concave surface constitute the first lens surface with respect to the area of each of the convex surface and the concave surface constituting the first lens surface. Since the area of the portion overlapping each region of the concave surface is small, the difference in the repetition interval between the first lens surface and the second lens surface is large. For this reason, it is possible to avoid that the image distortion due to the two lens surfaces reinforces each other, and that the overall image deformation is not mutually enhanced.

According to the invention described in claim 10, when the two-dimensional display image is viewed through the curved lens, the following effects of the curved lens appear in the image of the display image.

Since the image is deformed by the first lens surface and becomes different images for the right eye and the left eye, the two-dimensional display image looks like a three-dimensional image with a sense of depth.

In addition, the deformation of the image viewed as a three-dimensional image by the first lens surface is a smooth deformation and does not involve a sudden deformation, so that the image quality can be maintained at a certain level.

In addition, the second lens surface further greatly changes only the position of the first lens surface in the depth direction of the entire image, and the appearing three-dimensional effect is further enhanced.

According to the invention described in claim 11, since the image of the minute convex surface or the minute concave surface can be regarded as a pixel of the whole image, the number of pixels can be equivalently increased, and the resolution of the whole image can be increased. Can be improved.

According to the invention described in claim 12, when the two-dimensional display image is viewed through the curved lens, the following effects of the curved lens appear on the image of the display image. The image is distorted by each lens surface that overlaps the multilayer. This causes a difference in the images formed in the retinas of the right and left eyes. As a result, the two-dimensional display image appears as a three-dimensional image with a sense of depth.

In addition, since the repetition interval between the concave and convex surfaces that constitute each lens surface overlapping in the multilayer is different, the image difference between the eyes changes from a relatively wide range to a relatively narrow range. There is such a change, and therefore, a three-dimensional effect can be felt both in an image part having a large area and an image part having a small area, and a stronger three-dimensional effect can be obtained by mutually strengthening the two parts.

The extent of image distortion due to individual lens surfaces in a multilayer stack is different from the extent of image distortion due to other lens surfaces. Therefore, it is possible to avoid compromising the overall image distortion. As a result, it is possible to suppress the image distortion and to further enhance the appearance of the three-dimensional effect.

Further, since the lens surface is a smooth curved surface, the deformation of the image is a smooth deformation, and is not accompanied by a sudden deformation, so that the image quality can be maintained at a certain level. According to the invention described in claim 13, when the two-dimensional display image is viewed through the curved lens, the following effects of the curved lens appear on the image of the displayed image.

In the whole image, a large number of regions having a difference in size corresponding to the small convex surface or the small concave surface of the lens surface are distributed. In this way, even when a region with a difference between the binocular images is distributed in the entire image, a three-dimensional effect with a sense of depth appears in the entire image. Also, as for the distortion, a distortion having a magnitude corresponding to the small convex surface and the small turning surface is distributed.

Since a distortion having a size corresponding to the small convex surface and the small concave surface will be distributed, it is possible to make the distortion such that the distortion is not so much disturbed with respect to the whole image.

Furthermore, the thickness of this lens can be reduced because the individual convex or concave surfaces of the lens are both relatively narrow.

The invention of the display device described in claim 14 has the following effects when a two-dimensional display image is viewed through a curved lens.

In any of the curved lenses according to claims 1 to 13, different images are formed between the right eye and the left eye by being deformed by the curved lens, so that the two-dimensional display image has a sense of depth. It looks like a solid three-dimensional image. According to the invention set forth in claim 15, a communication image or a broadcast image can be used, and a use area is greatly expanded.

According to the invention as set forth in claim 16, since there is a means for holding the display image at a predetermined distance from the lens surface, a three-dimensional effect of a desired strength can be stably secured.

According to the invention described in claim 17, the distance between the display element for displaying the two-dimensional display image and the curved lens can be freely varied, and appears by adjusting the distance as needed. You can adjust the stereoscopic effect.

According to the invention set forth in claim 18, a three-dimensional image with limited distortion can be obtained.

According to the invention as set forth in claim 19, the curved lens is circulated with the curved lens attached to the holding mechanism first.

The effects have been described for each claim. Further, effects common to a plurality of claims will be described.

In many of the claims, the lens surface is a curved surface of the Fresnel lens type, but the lens thickness can be reduced by using the Fresnel lens type. In particular, it is necessary to reduce the radius of curvature of the lens surface when placing a curved lens close to a two-dimensional display image, and the effective area is large when placing it in front of a display image, etc. If the lens thickness is not a Fresnel lens type, the thickness may be difficult to be realized in practice, and in a curved lens applied to a display device, the lens surface of the Fresnel lens type is extremely important and effective. It is.

In each of the embodiments of the present invention, a displayed image is viewed through a lens, and a unique transparent feeling appears in the image viewed through the lens. The color tone is also vivid, and the image looks brilliant. This effect alone has utility.

In the display device of the present invention, there is no strict condition on the positional relationship between the curved lens and the display image. Moreover, the display image may be a two-dimensional display image of a continuous pattern such as a general photograph or picture, and a special operation such as processing an image is not necessarily required. Therefore, the configuration of the apparatus can be made easily and inexpensively. All publications, patents and patent applications cited in this specification are incorporated herein by reference as they are. Industrial applicability

The present invention provides a display device for displaying a two-dimensional image as a three-dimensional image having a sense of depth. Further, a curved lens used for the display device is provided.

Claims

The scope of the claims

1.The lens surface has any one of a single smooth concave surface, a single smooth convex surface, or a smooth curved surface in which concave and convex surfaces are alternately arranged, or a single smooth concave surface. The lens surface has a Fresnel lens type surface having either a single smooth convex surface or a smooth curved surface in which concave and convex surfaces are alternately arranged as a mother curved surface,

The effective area or shape is rectangular,

The lens surface or the generating surface has a direction with the largest curve change at an arbitrary point, and a plane including the direction with the largest curve change and perpendicular to the rectangle is one side of the rectangle. A curved lens with an angle between 30 and 60 degrees.

2.A convex surface constituting the virtual array surface, wherein any one of a single smooth concave surface, a single smooth convex surface, or a smooth curved surface in which concave and convex surfaces are alternately arranged is used as a virtual array surface. A lens surface having a smooth curved surface formed by alternately arranging small convex surfaces and small concave surfaces along the imaginary arrangement surface in which the area of a portion overlapping each of the concave regions is small with respect to the area of each concave region; or The small convex surface and the small concave surface having a small area of a portion overlapping with each of the regions are alternately arranged along the virtual arrangement surface with respect to the area of each of the convex and concave regions constituting the virtual array surface. A curved lens having a Fresnel lens-type surface with a smooth curved surface as a base curved surface.

3. The curved lens according to claim 2, wherein the small convex surface and the small concave surface are arranged at substantially the same size and repetition interval, and the surface gradient changes are substantially the same.

4. The area of the portion where the small convex surface and the small concave surface overlap each of the regions is less than or equal to 1/4 of the area of each region of the 配列 surface or the concave surface constituting the virtual arrangement surface. 4. The curved lens according to any one of items 2 or 3.

5. The virtual array surface is defined as any one of a single smooth concave surface, a single smooth convex surface, or a smooth curved surface in which concave and convex surfaces are alternately arranged. Effectively, only the minute convex surface or only the minute concave surface, in which the area of the portion overlapping with each of the regions is sufficiently small, is arranged along the virtual array surface with respect to the area of each of the formed convex or concave regions. A force having a curved surface as a lens surface, or only a small convex surface or a minute concave surface in which the area of a portion overlapping with each of the regions is effectively small with respect to the area of each of the convex or concave regions constituting the virtual array surface. A curved surface lens having, as a lens surface, a surface in the form of a Frennner lens having a curved surface obtained by arranging only the surfaces along the virtual arrangement surface as a base curved surface.

6. The curved lens according to claim 5, wherein an area force of a portion where the minute convex surface or the minute concave surface overlaps with each of the regions is equal to or less than an area force of the effective region / 100.

7.A single smooth concave surface, a single smooth convex surface, or a smooth curved surface in which concave and convex surfaces are alternately arranged as a first lens surface, or a single smooth concave surface The first lens surface is a Fresnel lens-type surface having any one of a concave surface, a single smooth convex surface, or a smooth curved surface in which concave and convex surfaces are alternately arranged as a mother curved surface. The second lens forms a smooth curved surface formed by alternately arranging small convex surfaces and small concave surfaces having a small area of a portion overlapping with each of the above-described regions with respect to the area of each of the convex or concave regions constituting the lens surface of the second lens. A curved lens having a surface, wherein the first lens surface and the second lens surface are laminated.

8. The curved lens according to claim 7, wherein the small convex surface and the small turning surface are arranged at substantially the same size and repetition interval, and the state of change of the surface gradient is substantially the same. .

9. The area of the portion where the small convex surface and the small concave surface overlap each of the regions is 1/4 or less of the area of each of the convex and concave regions constituting the first lens surface. Item 9. A curved lens according to any one of Items 7 to 8.

10. A surface in the form of a Fresnel lens whose first curved surface is one of a single smooth concave surface, a single smooth convex surface, or a smooth curved surface in which concave and convex surfaces are alternately arranged is defined as the first surface. Effectively, only the small convex surface or only the small 囬 surface, in which the area of the portion overlapping with each of the regions is sufficiently small with respect to the area of each of the convex and concave regions constituting the first lens surface, is set as the lens surface. A curved lens in which a curved surface formed as an array is a second lens surface, and the first lens surface and the second lens surface are stacked.

11. The curved lens according to claim 10, wherein an area of a portion where the minute convex surface or the minute concave surface overlaps each of the regions is 1/100 or less with respect to an area of the effective region.

12. Either one or both of a smooth lens surface with concave and convex surfaces alternately arranged, or a Fresnel lens type surface with a smooth curved surface with concave and convex surfaces alternately arranged as a base surface A curved surface lens in which the repetition interval between the concave surface and the convex surface constituting the lens surface of each layer is different from the repetition interval between the concave surface and the convex surface constituting the lens surface of the other layer.

13.The lens surface has a smooth curved surface formed by alternately arranging small convex surfaces or small concave surfaces, and the area of each small convex surface or small concave surface is 1/20 or less of the effective area. A curved lens.

14.A display screen for displaying the two-dimensional display image and the curved lens so that a two-dimensional display image consisting of continuous design force can be observed through the curved lens according to claims 1 to 13. A display device comprising:

15. The communication device according to claim 14, further comprising a communication image or broadcast image receiving means.

16. The display device according to claim 14, further comprising means for holding the curved lens and the display screen at a predetermined distance.

17. The display device according to claim 16, wherein the predetermined distance is adjustable.

18. The display device according to claim 16, wherein the predetermined distance is not more than 12 times a focal length of the curved lens.

19. A structure for a display device according to any one of claims 14 to 18, comprising the curved lens and a holding mechanism for holding the display screen.