JP2014126729A - Three-dimensional(3d) display and display drive method - Google Patents

Abstract

In a 3D display without glasses, a 3D display and a display driving method capable of increasing the number of viewpoints without reducing the resolution of a stereoscopic image are obtained.
A main display 10 that emits incident light as linearly polarized light, and whether light emitted from the main display 10 is emitted while maintaining a polarization state, or is emitted with a polarization direction rotated by 90 °. A sub-display 20 that can be switched at a driving speed more than twice the driving speed of the main display 10, and a lenticular lens 30 that gives different refractive indexes to the two types of linearly polarized light emitted from the sub-display 20. Prepare.
[Selection] Figure 1

Description

  The present invention relates to a glasses-less 3D display and a display driving method.

  Conventionally, as a 3D display, a system with glasses and a system without glasses are known. For example, as a method with glasses, a shutter glasses method in which parallax is generated by switching between a right-eye image and a left-eye image at high speed and the glasses simultaneously block the left and right fields of view. It has been known.

  As another system with glasses, as shown in FIG. 5, a circularly polarized glasses system using a polarization filter that passes only circularly polarized light in a specific rotation direction and discards reversely polarized circularly polarized light is known. Furthermore, as shown in FIG. 6, an active retarder method is known in which the amplitude direction of linearly polarized light is temporally switched.

  On the other hand, as a method without glasses, a parallax barrier method is known in which a binocular parallax is created by placing a shielding plate with grooves for each of two left and right pixels in front of the display. Further, as another method without glasses, a lenticular lens method is known in which a binocular parallax is generated by arranging a lenticular lens having a shape (kamaboko shape) in which thin semicylinders are arranged in front of the display.

  Here, FIG. 7 illustrates a lenticular lens type 3D display. In FIG. 7, the lenticular lens is optically isotropic. FIG. 7 shows a case where the number of viewpoints (described later) is 1.

JP 2003-158752 A

However, the prior art has the following problems.
In the 3D display with glasses, there is a problem in that each system has to wear dedicated glasses. The cause of this problem is that there is a principle restriction that the images entering the left and right eyes are changed by the glasses.

  In addition, the shutter glasses type 3D display has a problem that the weight of the glasses increases and the cost increases. The cause of this problem is that the glasses need to have a drive circuit as a mechanism for operating the shutter.

  In addition, the parallax barrier type 3D display has a problem that the luminance is lower (the image becomes darker) than the lenticular lens type 3D display. The cause of this problem is that there is a principle restriction that it is necessary to provide a barrier (shielding plate) between the light source and the eyes.

  In addition, in the 3D display without glasses, there is a problem that the area (number of viewpoints) in which a 3D image can be clearly visually recognized is limited in each system. The cause of this problem is that there is a principle restriction that the point where the 3D image is focused is limited to, for example, only the front.

  In order to solve this problem, there is a problem in that the resolution of the 3D spatial video is reduced to 1 / r when measures are taken to increase the number of viewpoints (r) (see, for example, Patent Document 1). The cause of this problem in the 3D display without glasses is that it is necessary to set the same number of pixels as the number of viewpoints (r) as one set.

  The present invention has been made to solve the above-described problems. In a 3D display using glasses, the number of viewpoints can be increased without reducing the resolution of a stereoscopic image (3D spatial image). It is an object to obtain a 3D display and a display driving method.

  The 3D display according to the present invention emits incident light as linearly polarized light, and emits light emitted from the main display while maintaining the polarization state, or rotates the polarization direction by 90 ° and emits the light. A sub-display that can be switched at a driving speed more than twice the driving speed of the main display, and a lenticular lens that gives different refractive indexes to the two types of linearly polarized light emitted from the sub-display Is.

  The display driving method according to the present invention includes: a first polarization step that emits incident light as linearly polarized light; and the emitted light that is emitted in the first polarization step is emitted while maintaining a polarization state. Alternatively, the second polarization step for switching whether the polarization direction is rotated by 90 ° at a speed more than twice the first polarization step and the two types of linearly polarized light emitted at the second polarization step are refracted differently. And an image forming step in which images are refracted at a rate and imaged at different positions.

According to the 3D display of the present invention, the main display emits the incident light as linearly polarized light, and the sub-display emits the emitted light from the main display while maintaining the polarization state, or the polarization direction. Is rotated at a driving speed that is at least twice the driving speed of the main display, and the lenticular lens refracts the two types of linearly polarized light emitted from the sub-display with different refractive indexes.
According to the display driving method of the present invention, the first polarization step emits the incident light as linearly polarized light, and the second polarization step polarizes the outgoing light emitted in the first polarization step. Switching between exiting while maintaining the state or rotating by rotating the polarization direction by 90 ° is switched at a speed more than twice that of the first polarization step, and the imaging step is output at the second polarization step. Different types of linearly polarized light are refracted at different refractive indexes and imaged at different positions.
Therefore, in the 3D display without glasses, the number of viewpoints can be increased without reducing the resolution of the stereoscopic video.

It is a block diagram which shows the 3D display which concerns on Embodiment 1 of this invention. It is a block diagram which shows the lenticular lens of 3D display which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows operation | movement (at the time of a sub display OFF) of the 3D display which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows operation | movement (at the time of a sub display ON) of the 3D display which concerns on Embodiment 1 of this invention. It is explanatory drawing which illustrates 3D display of a circularly polarized glasses system. It is explanatory drawing which illustrates the 3D display of an active retarder system. It is explanatory drawing which illustrates the 3D display of a lenticular lens system.

  Hereinafter, preferred embodiments of a 3D display and a display driving method according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts will be described with the same reference numerals.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a 3D display 1 according to Embodiment 1 of the present invention. In FIG. 1, the 3D display 1 includes a main display 10, a sub display 20, and a lenticular lens 30, and is arranged in the order of the lenticular lens 30, the sub display 20, and the main display 10 as viewed from the observer.

  The main display 10 is, for example, a liquid crystal display (LCD: Liquid Crystal Display), and emits incident light as linearly polarized light. The main display 10 is not limited to the LCD, and may be other types of displays such as an organic EL display (OLED: Organic Light Emitting Display) as long as it can emit linearly polarized light by attaching a polarizing plate. .

  Further, the polarization direction of the light emitted from the main display 10 and the orientation direction (rubbing axis) of the incident-side substrate of the sub display 20 coincide with each other.

  The sub display 20 is an LCD that can be driven at a high speed, and emits light emitted from the main display 10 while maintaining the polarization state by turning on / off the voltage, or shifts the phase by half a wavelength (λ / 2). It is possible to switch whether to emit (by rotating the polarization direction by 90 °).

  Specifically, the sub-display 20 is driven by a driving circuit (not shown) and operates at a driving speed that is twice or more that of the main display 10. The sub-display 20 may be a nematic liquid crystal or a smectic liquid crystal (Ferroelectric Liquid Crystal (FLC)). Further, the electrode of the sub display 20 may be a solid electrode or a patterning electrode.

  Here, the two types of linearly polarized light emitted from the sub display 20 are incident on either the X axis or the Y axis of the lenticular lens 30 in parallel.

  The lenticular lens 30 is made of a liquid crystalline material that is uniaxially oriented on either the X axis or the Y axis, and has a characteristic that the refractive index differs between the X axis and the Y axis, so-called birefringence (optical anisotropy). doing. Further, the surface of the lenticular lens 30 is not flattened in order to diffuse light in a plurality of directions.

  Here, the lenticular lens 30 is formed of a birefringent material such as a liquid crystal polymer, for example, the refractive index in the longitudinal direction (for example, the X axis) is ne, and the short direction (for example, the Y axis). The refractive index of is no.

  The lenticular lens 30 may be polymerized after alignment using polymerizable liquid crystal, or may be polymer liquid crystal. Further, the alignment method of the liquid crystal in the lenticular lens 30 may be a rubbing method, a photo alignment method, or a method of giving a shear (shear).

  The main display 10, the sub display 20, and the lenticular lens 30 may each have a flexible configuration.

  Hereinafter, the operation of the 3D display 1 according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 3 shows the operation of the 3D display 1 when the sub display 20 is off, and FIG. 4 shows the operation of the 3D display 1 when the sub display 20 is on.

  Further, here, as an example, the sub-display 20 is a TN (Twisted Nematic) type LCD, and the refractive index ne in the longitudinal direction of the lenticular lens 30 is larger than the refractive index no in the lateral direction (ne> no). explain.

  In FIG. 3, when the sub display 20 is off, the vibration direction of the emitted light (linearly polarized light) from the main display 10 is rotated by 90 ° on the sub display 20. Therefore, the vibration direction of the polarized light emitted from the sub-display 20 coincides with the longitudinal direction of the lenticular lens 30, and the light passing through the lenticular lens 30 is refracted at the refractive index ne.

  On the other hand, in FIG. 4, when the sub display 20 is on, the vibration direction of the emitted light (linearly polarized light) from the main display 10 passes through the sub display 20 because the liquid crystal stands. Is not changed. Therefore, the vibration direction of the polarized light emitted from the sub-display 20 matches the short direction of the lenticular lens 30, and the light passing through the lenticular lens 30 is refracted with a refractive index no.

  Here, when the sub display 20 is off (in the case of FIG. 3) and when the sub display 20 is on (in the case of FIG. 4), since ne> no, the light passing through the lenticular lens 30 in FIG. The image is formed at a position closer to the lenticular lens 30 (L1 <L2) than the light that has passed through the lenticular lens 30 in FIG.

  That is, by switching the sub display 20, the imaging position of the light emitted from the lenticular lens 30 can be changed.

  At this time, the state shown in FIG. 3 is obtained by switching the sub display 20 at a high speed at a driving speed (that is, 120 Hz = 1/120 s) twice that of the main display 10 (for example, 60 Hz = 1/60 s). And the state shown in FIG. 4 can be switched at high speed.

  As a result, the observer can see the 3D image at both the imaging position in FIG. 3 and the imaging position in FIG. 4. That is, the number of viewpoints can be increased without reducing the resolution of the 3D image (spatial image). Specifically, in this example, the number of viewpoints can be doubled.

As described above, according to the first embodiment, the main display emits the incident light as linearly polarized light, and the sub display emits the emitted light from the main display while maintaining the polarization state. Alternatively, the polarization direction is rotated by 90 ° to switch the output at a driving speed more than twice the driving speed of the main display, and the lenticular lens converts the two types of linearly polarized light emitted from the sub display with different refractive indexes. Refract.
Therefore, in the 3D display without glasses, the number of viewpoints can be increased without reducing the resolution of the stereoscopic video.

Further, since the sub display is an LCD, the sub display can be manufactured in the same process as the main display, and there is no need to provide new manufacturing equipment.
In addition, by configuring the lenticular lens from a uniaxially oriented liquid crystalline material, two types of linearly polarized light emitted from the sub-display can be imaged at mutually different focal positions, and the number of viewpoints can be increased.

  1 3D display, 10 main display, 20 sub-display, 30 lenticular lens.

Claims (4)

A main display that emits incident light as linearly polarized light;
The light emitted from the main display can be switched at a driving speed more than twice the driving speed of the main display, whether the light is emitted while maintaining the polarization state or the polarization direction is rotated by 90 °. A sub-display,
A lenticular lens that gives different refractive indexes to the two types of linearly polarized light emitted from the sub-display;
3D display with The 3D display according to claim 1, wherein the sub-display is a liquid crystal display. The 3D display according to claim 1, wherein the lenticular lens is made of a uniaxially oriented liquid crystalline material. A first polarization step for emitting incident light as linearly polarized light;
Switch whether the outgoing light emitted in the first polarization step is emitted while maintaining the polarization state or the polarization direction is rotated by 90 ° at a speed more than twice that of the first polarization step. A second polarization step;
An imaging step of refracting the two types of linearly polarized light emitted in the second polarization step with different refractive indexes to form images at different positions;
A method of driving a display having

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