JP2000075243A - Stereoscopic display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a practicable stereoscopic display device capable of displaying three-dimensional images of a simple type with a simple structure without using spectacles, etc. SOLUTION: This display device has a panel LED array 13 for executing image display, a light emission type two-dimensional image display section consisting of a collimator 12 for emitting the illumination light of this plane LED array 13 as approximately parallel beams and an electronic control screen 11 which consists of plural laminated scattering type liquid crystal display elements 15 and constitutes the three-dimensional images. The device is so constituted as to successively switch the scattering type liquid crystal display elements 15 which emit the light of the respective cut face images formed by successively cutting the three-dimensional materials to be displayed from the end as two-dimensional images and display these images in synchronization with the respective two-dimensional images to be subjected to light emission in the light emission type two-dimensional image display section described above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional display device, and more particularly to a three-dimensional display device for displaying a three-dimensional image by superposing and stacking a plurality of two-dimensional images displayed on a two-dimensional display panel.

[0002]

2. Description of the Related Art As a conventional three-dimensional display device, for example, a device using liquid crystal shutter glasses shown in FIG. 8 is known. In the apparatus shown in FIG. 8, first, the three-dimensional object 5 is viewed from different directions.
In order to obtain a so-called parallax image of the image 1, a three-dimensional object 51 is provided by two cameras 52 and 53 installed at a predetermined interval.
Is imaged.

Next, the video signal converter 54 synthesizes the two-dimensional images so that the two-dimensional images picked up by the cameras 52 and 53 are alternately arranged for each field. The video signal conversion device 54 displays the synthesized two-dimensional image on the two-dimensional display device 55, and when displaying the two-dimensional image captured by the camera 52, the liquid crystal shutter glasses 56.
Among them, the liquid crystal shutter on the left side of the observer 57 is set to the transmitting state, and the right side is set to the non-transmitting state.

On the other hand, a video signal converter 54
Is displayed on the two-dimensional display device 55 by the observer 57 in the liquid crystal shutter glasses 56.
The liquid crystal shutter on the right side is set to a transmission state, and the liquid crystal shutter on the left side is set to a non-transmission state. By repeating the above-described operation, the observer 57 feels as if they are simultaneously viewing the parallax image with both eyes due to the afterimage effect of the eyes, so that stereoscopic viewing with binocular parallax can be performed.

As another three-dimensional display device using no glasses or the like, for example, a three-dimensional display device using a well-known lenticular lens plate shown in FIG. 9 is known. In this apparatus, first, a parallax image of a three-dimensional object 51 is formed by cameras 52,
An image is taken at 3. Next, from the two two-dimensional images captured by the cameras 52 and 53, the video signal conversion unit 54 synthesizes a two-dimensional image in which pixels in the horizontal direction are alternately arranged for each pixel.

The video signal converter 54 causes the two-dimensional display device 55 to display the synthesized two-dimensional image. At this time, the lenticular lens plate 5 is provided on the display surface side of the two-dimensional display device 55.
Since the lenticular lens plate 58 has directivity by closely arranging the lenses 8, the camera 52 and the camera 53 scan the left and right eyes of the observer 57 depending on the position of the observer 57. Only the pixels of the obtained two-dimensional image are recognized. Therefore, on both days of the observer 7, the parallax images captured at the predetermined intervals are respectively visible, and a stereoscopic image corresponding to the binocular parallax is formed.

[0007]

However, a conventional stereoscopic display device using liquid crystal shutter glasses always has
You have to wear liquid crystal shutter glasses, which is unnatural. On the other hand, in a stereoscopic display device using a lenticular lens, the range in which a parallax image can be observed with both eyes is limited to a narrow range, and thus the observer 57 cannot freely select a position with respect to the two-dimensional display device 55.

Further, in a three-dimensional display device using liquid crystal shutter glasses and a three-dimensional display device using a lenticular lens, the eye of the observer 57 is often focused on the surface of the display device and displayed. Since there is no change due to the image, and a contradiction occurs between the displayed image recognized by the observer 7 and the focus position of the eye, eyestrain may be caused.

The two-dimensional image displayed on the display device is
Since it is fixed at the viewpoint position determined by the positions of the cameras 52 and 53, dynamic parallax cannot be expressed. For example, when the observer 57 moves, the image displayed on the display device moves together. Because it feels like
There was a problem of giving a strange feeling to the observer.

It is an object of the present invention to satisfy the physiological factors of stereoscopic vision, such as binocular parallax, focus adjustment, and dynamic parallax, without using glasses or the like, and to provide an electrically rewritable image display. It is an object of the present invention to provide a three-dimensional display device capable of performing the following.

[0011]

A three-dimensional display device according to the present invention is a three-dimensional display device for displaying a three-dimensional object as a three-dimensional image, and includes a flat LED array for displaying an image and the flat LED array. A two-dimensional image display unit including a collimator for emitting the illumination light as substantially parallel light, and an electronic control screen including a plurality of stacked liquid crystal display elements for forming a three-dimensional image. And
The light-emitting type two-dimensional image display unit emits, as two-dimensional images, respective cut plane images obtained by sequentially cutting a three-dimensional display object from an end, and displays the images in synchronization with the issued two-dimensional images. The liquid crystal display elements are configured to be sequentially switched.

Further, the collimator comprises at least two pinhole arrays arranged at a predetermined interval.

Further, the collimator is characterized by comprising at least one pinhole array having a predetermined aspect ratio.

The collimator includes a pinhole array and at least one microlens array provided on the electronic control screen side of the pinhole array, and the focal positions of a large number of microlenses constituting the microlens array are determined by the pin positions. The microlens array and the pinhole array are arranged so as to be located on the same plane as the surface of the hole array on the side of the microlens array.

(Effect) Each cut plane image obtained by cutting the three-dimensional display object in order from the end is emitted as a two-dimensional image by the light-emitting two-dimensional image display unit, and the electronic control screen is irradiated. At this time, the scattering type liquid crystal element for displaying the emitted two-dimensional image is set to the scattering state, and the other scattering type liquid crystal elements are set to the transmission state. As a result, the observer sees a two-dimensional image brightly displayed on the scattering type liquid crystal element in the scattering state.

Further, in synchronization with the two-dimensional image sequentially emitted from the light-emitting type two-dimensional image display unit, the two-dimensional image is displayed while sequentially switching the scattering type liquid crystal elements to be displayed. Therefore, the observer observes the two-dimensional images displayed one after another on each of the stacked scattering type liquid crystal elements. As a result, due to the afterimage phenomenon of the observer, the cut surface images are collectively observed as a three-dimensional image (three-dimensional image) on the electronic control screen.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a block diagram illustrating a schematic configuration of a stereoscopic display device, FIG. 2 is a schematic cross-sectional view illustrating a main part of an electronic control screen including a plurality of stacked scattering liquid crystal elements, and FIG. FIG. 3 is a schematic perspective view showing a state in which a plurality of scattering type liquid crystal elements to be formed are stacked.

The three-dimensional display device according to the present embodiment includes a flat LED array 13 and a collimator 12 for converting light into substantially parallel light.
And an electronic control screen 11 composed of a polymer dispersed liquid crystal element 15 as a plurality of scattering liquid crystal elements.

As shown in FIG. 2 and FIG. 3, the electronic control screen 11 is a two-dimensional image (indicated by the symbol D in the figure) of each cut plane image obtained by cutting the display object to be displayed in order from the end.
1, D2,...) Are stacked (eg, about 10).

As shown in FIG. 2, the polymer-dispersed liquid crystal elements 15 constituting the electronic control screen 11 are closely attached at equal intervals with a spacer 14 made of a transparent adhesive interposed therebetween. . The spacer 14 has a refractive index of glass, which is a material of the transparent substrates 1 and 2 of the polymer-dispersed liquid crystal element 15 (absolute refractive index n = optical glass (BK-7)).
1.519).

This is because, for example, when air enters the interface between the polymer-dispersed liquid crystal element 15 and the adjacent polymer-dispersed liquid crystal element 15, about 4% of the reflection occurs at one interface, and This is to prevent a value that cannot be ignored when the number of liquid crystal elements 15 increases. Since the spacer 14 prevents the interface reflection from occurring inside the electronic control screen 11, the electronic control screen 1
1 is a transparent rectangular parallelepiped made entirely of glass.

As shown in FIG. 2, the polymer-dispersed liquid crystal element 15 constituting the electronic control screen 11 is sandwiched between a pair of transparent substrates 1 and 2 made of glass and the pair of transparent substrates 1 and 2. And a sealing material 6 a, 6 b for sealing the polymer liquid crystal layer 5.
Further, electrodes 3 and 4 are formed on opposing surfaces of the pair of transparent substrates.

The surface of the polymer-dispersed liquid crystal element 15 usually scatters (diffuses) light (when no AC voltage is applied), and the electrodes 3, 4
When an AC voltage is applied to the substrate, a transparent transparent glass-like transmission state is obtained. Thus, each polymer-dispersed liquid crystal element 15 can be switched between a scattering state and a transmitting state.

Next, the operation of the stereoscopic display device according to this embodiment will be described. As shown in FIG. 1, the stereoscopic display device has a light-emitting two-dimensional image display in which an electronic control screen 11 in which a plurality of polymer dispersed liquid crystal elements 15 are layered is provided below the electronic control screen 11. Part 1
It is illuminated by 0. Light emitting type 2
Since the light of the flat LED array 13 constituting the two-dimensional image display unit 10 becomes parallel light by the collimator 12 and is irradiated perpendicularly to the surface of each polymer dispersed liquid crystal element 15,
It is projected on the position of the polymer dispersed liquid crystal element 15 of the electronic control screen 11 selected in the scattering state.

Therefore, the polymer-dispersed liquid crystal element 15 in the scattered state becomes a virtual light source determined by a display pattern reflecting each cut plane image of the display object emitted from the light-emitting type two-dimensional image display section 10 and brightly displays. Is done. Further, by changing the color of the flat LED array 13, the three-dimensional image 23 displayed on the electronic control screen 11 can be displayed in red or green instead of white.

Next, a method for displaying a three-dimensional image using the three-dimensional display device according to the present invention will be described. First, FIG.
Is a computer (not shown).
Alternatively, from the information of the display object stored in an external memory (not shown), each cut plane image cut in order from the end of the display object is calculated, and the information of each of the cut plane images is converted into a light-emitting two-dimensional image. It is sent to the display unit 10. Subsequently, the light emitting type two-dimensional image display unit 1
A polymer dispersed liquid crystal element 15 that emits a two-dimensional image of each section plane image from 0 and displays the emitted two-dimensional image
In a scattering state, a two-dimensional image of a cut plane image is displayed on a predetermined polymer-dispersed liquid crystal element 15.

At this time, the two-dimensional images (D1, D2,...) Of the respective cut plane images emitted from the light emitting type two-dimensional image display unit 10 are displayed.
The polymer dispersed liquid crystal element 15, which is displayed in synchronization with an image similar to the above, is sequentially switched to the scattering state, and the two-dimensional image (D
, D2... Are displayed. As a result, the observer 13 who observes from above the electronic control screen 11 can see the three-dimensional image 23 due to the afterimage phenomenon.

In this embodiment, a single-color static three-dimensional image is displayed on the electronic control screen 11. However, the flat LED array 13 is composed of red, blue, and green LEDs for color display. Comprising each polymer dispersed liquid crystal element 15
By switching and illuminating each color in synchronization with the display on the display, color display of a three-dimensional image is also possible.

(First Embodiment) Next, a first embodiment of a light emitting type two-dimensional image display unit will be described. FIG.
FIG. 5 is a schematic diagram illustrating a part of a configuration of a light-emitting two-dimensional image display unit according to the first embodiment of the present invention. FIG. 5 is a schematic diagram illustrating a part of a configuration of a light-emitting two-dimensional image display unit according to the present embodiment. It is a top view.

As shown in FIGS. 4 and 5, the light emitting type two-dimensional image display unit 10 includes a collimator 12 and a flat LED array 13. The planar LED array 13
It is composed of a number of LEDs 19 arranged in a matrix. The collimator 12 includes two pinhole arrays 16 arranged at a predetermined interval.

The distance between the two pinhole arrays 16 is set such that the light emitted from the collimator 12 and illuminating each polymer dispersed liquid crystal element 15 becomes substantially parallel light. Further, the pinhole array 16 includes a large number of pinholes 20 arranged so as to correspond to a large number of the LEDs 19 arranged in a matrix on a one-to-one basis.

As described above, according to the present embodiment, the polymer constituting the electronic control screen 11 (not shown) has a simple structure in which the two pinhole arrays 16 shown in FIG. The dispersion type liquid crystal element 15 can be irradiated with substantially parallel light.

(Second Embodiment) Next, a second embodiment of the light emitting type two-dimensional image display unit will be described. FIG. 6 (a)
FIG. 7 is a schematic diagram illustrating a part of a configuration of a light-emitting two-dimensional image display unit according to a second embodiment of the present invention. FIG.
(B) is a schematic partial enlarged view of the pinhole array 16a that constitutes the light emitting type two-dimensional image display unit.

As shown in FIGS. 6A and 6B, the light emitting type two-dimensional image display unit 10a includes a single pinhole array 16a having a predetermined thickness b as a collimator,
And a flat LED array 13. Flat LED
The array 13 is composed of a large number of LEDs 19 arranged in a matrix as in the first embodiment.

The pinhole array 16a is composed of a large number of pinholes 20a arranged in a one-to-one correspondence with a large number of the LEDs 19 arranged in a matrix as in the first embodiment. . Further, FIG.
As shown in the figure, a pinhole array 1 as a collimator
The aspect ratio b / d of the thickness b of the layer 6a and the diameter d of the pinhole 20a is such that the light emitted from the pinhole array 16a as the collimator and illuminating each polymer dispersed liquid crystal element 15 becomes substantially parallel light. Set as follows.

As described above, according to the present embodiment, similarly to the first embodiment, the predetermined aspect ratio b /
With a simple structure in which a single pinhole array 16a having d is arranged, it is possible to irradiate substantially parallel light to the polymer dispersed liquid crystal element 15 constituting the electronic control screen 11 (not shown).

(Third Embodiment) Next, a third embodiment of the light emitting type two-dimensional image display unit will be described. FIG. 7 (a)
FIG. 9 is a schematic diagram illustrating a part of a configuration of a light-emitting two-dimensional image display unit according to a third embodiment of the present invention.

FIG. 7B is a schematic partial enlarged view of a light emitting type two-dimensional image display section. As shown in FIG. 7A, the light-emitting two-dimensional image display unit 10b includes a collimator 12b and a flat LED array 13. The flat LED array 13 is composed of a large number of LEDs 19 arranged in a matrix as in the first embodiment.
Also, the collimator 12b is a single pinhole array 1
6b and a polymer-dispersed liquid crystal element 15 forming an electronic control screen 11 (not shown) of the pinhole array 16b.
And one microlens array 18 arranged on the side.

The pinhole array 16b is composed of a large number of pinholes 20b arranged in a one-to-one correspondence with a large number of the LEDs 19 arranged in a matrix as in the first embodiment. The microlens array 18 is also composed of a large number of microlenses 21 arranged so as to correspond to a large number of the LEDs 19 arranged in a matrix on a one-to-one basis.

As shown in FIG. 7B, the focal position P of the microlens 21 is different from that of the pinhole array 1.
The pinhole array 16b and the microlens array 18 are arranged so as to be located on the same plane as the surface 26 of the 6b on the side of the microlens array 18. Further, the light emitted from the pinhole 20b is reflected by the opening f of the microlens 21.
It is desirable to set the dimensions of each part of the pinhole array 16b to such an extent as to spread the whole. In other words, it may be set so that light emitted from one pinhole 20b does not enter the microlenses 21 on both sides.

As described above, according to this embodiment, the electronic control screen 11 (not shown) is provided by arranging the single pinhole array 16b and the microlens array 18 shown in FIG. Can be irradiated with parallel light.

In this embodiment, the collimator is arranged so as to correspond to a large number of LEDs arranged in a matrix in a one-to-one manner.
A plurality of collimators may be arranged so as to function for (light source). That is, the same effect can be obtained even if the pitches of the pinhole array and the microlens array are made smaller than the pitch of a large number of LEDs arranged in a matrix.

[0043]

As described above, according to the present invention, since a scattering type liquid crystal element is used as an electronic control screen, the transmittance is high even if many sheets are stacked, the wavelength dispersion of transmission characteristics is small, and the structure is simple. 3D display device can be realized,
Full color can be easily realized. Further, the structure of the collimator for irradiating substantially parallel light to the electronic control screen is simple, and a compact and inexpensive stereoscopic display device can be realized. As a result, a three-dimensional display of the time of the clock and a three-dimensional display of the display screen of the small game machine can be realized with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a stereoscopic display device according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing a main part of an electronic control screen including a plurality of polymer-dispersed liquid crystal elements stacked in the embodiment of the present invention.

FIG. 3 is a schematic perspective view showing a state in which a plurality of polymer dispersed liquid crystal elements according to the embodiment of the present invention are stacked.

FIG. 4 is a schematic diagram showing a part of the configuration of a light-emitting two-dimensional image display unit according to the first embodiment of the present invention.

FIG. 5 is a schematic plan view showing a part of the configuration of a light-emitting two-dimensional image display unit according to the first embodiment of the present invention.

FIG. 6 is a schematic diagram illustrating a part of a configuration of a light-emitting two-dimensional image display unit according to a second embodiment of the present invention.

FIG. 7 is a schematic diagram showing a part of the configuration of a light-emitting two-dimensional image display unit according to a third embodiment of the present invention.

FIG. 8 is a block diagram showing a schematic configuration of a stereoscopic display device using conventional liquid crystal shutter glasses.

FIG. 9 is a block diagram showing a schematic configuration of a stereoscopic display device using a conventional lenticular lens plate.

[Explanation of symbols]

1, 2 Transparent substrate 3, 4 Electrode 5 Polymer liquid crystal layer 6a, 6b Sealing material 10, 10a, 10b Light source means 11 Electronic control screen 12, 12b Collimator 13 Flat LED array 14 Spacer 15 Polymer dispersed liquid crystal element 16, 16a, 16b Pinhole array 17 Observer 18 Microlens array 19 LED 20, 20a, 20b Pinhole 21 Microlens 23 3D image 26 Surface of pinhole array on microlens array side D1, D2, D3, D4 2D image f Opening of micro lens P Focus position of micro lens

Claims (4)

[Claims] 1. A three-dimensional display device for displaying a three-dimensional display object as a three-dimensional image, comprising a plane LE for displaying an image.
A light emitting type two-dimensional image display unit including a D array and a collimator for emitting illumination light of the flat LED array as substantially parallel light, and a plurality of stacked scattering type liquid crystal display elements for forming a three-dimensional image. Electronic control screens, each of which emits, as a two-dimensional image, a cut plane image obtained by sequentially cutting a three-dimensional display object from an end in the light-emitting type two-dimensional image display unit, and outputs the two-dimensional image. A three-dimensional display device, wherein the scattering-type liquid crystal display elements to be displayed in synchronization with an image are sequentially switched. 2. The three-dimensional display device according to claim 1, wherein the collimator comprises at least two pinhole arrays arranged at a predetermined interval. 3. The three-dimensional display device according to claim 1, wherein said collimator comprises at least one pinhole array having a predetermined aspect ratio. 4. The collimator includes a pinhole array and at least one microlens array provided on the electronic control screen side of the pinhole array, and a focal position of a large number of microlenses constituting the microlens array is adjusted. The stereoscopic display device according to claim 1, wherein the microlens array and the pinhole array are arranged so as to be located on the same plane as a surface of the pinhole array on the side of the microlens array.