JP2011048286A - Optical member for stereoscopic image display, and stereoscopic image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical member for stereoscopic image display which reduces the occurrence of moire, and also to provide a stereoscopic image display device. <P>SOLUTION: The optical member for stereoscopic image display has a polarization axis control plate 180. The polarization axis control plate 180 has: a first polarization area 181; a second polarization area 182; and a polarization axis control plate area light shielding part 183 provided in a position corresponding to an image production area light shielding part 163, in a boundary part between the first polarization area 181 and the second polarization area 182 and shielding the whole or a part of image light for a right eye and image light for a left eye. The polarization axis control plate 180 emits the incident image light for a right eye and the incident image light for a left eye as linearly polarized lights whose polarization axes are orthogonal to each other or circularly polarized lights whose rotational directions of the polarization axes are opposite to each other, when the image light for a right eye and the image light for a left eye are made incident on the first polarization area 181 and the second polarization area 182 respectively. Microbeads are added to the polarization axis control plate area light shielding part 183. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a stereoscopic video display optical member and a stereoscopic video display device.

  As a device that allows an observer to recognize a stereoscopic image, an image generation unit that displays a right-eye image and a left-eye image in different regions, and straight lines in which polarization axes of polarized light incident on two different regions are orthogonal to each other There is known a stereoscopic image display device including a polarization axis control plate that emits polarized light or circularly polarized light whose polarization axis rotation directions are opposite to each other (see, for example, Patent Documents 1 to 5).

Japanese Patent Laid-Open No. 10-232365 JP 2004-264338 A JP-A-9-90431 JP 2008-304909 A JP 2002-185983 A

  However, in the techniques described in Patent Documents 1 to 5, moire may occur. Here, moire is also referred to as interference fringe, and is a striped pattern that is visually generated due to a shift in the period when a plurality of regularly repeated patterns are superimposed.

  For example, in the stereoscopic video display devices described in Patent Literature 4 and Patent Literature 5, video generation provided to reduce the occurrence of crosstalk and a region for generating a right-eye image, a region for generating a left-eye image, and the like. Crosstalk is generated by an image generation unit having a region light blocking unit, a first deflection region that transmits a right-eye image, and a first deflection region that transmits a left-eye image at a right angle to a deflection axis. A polarization axis control plate having a polarization axis control plate region light shielding portion provided for reduction, and the pitch between the image generation region light shielding portion and the polarization axis control plate region light shielding portion is approximate, Moire is likely to occur. In general, when there are two regularly repeated patterns, when the interval (period) of the first pattern is p and the interval (period) of the second pattern is p + δp, the generated moire interval ( (Period) d is expressed using the following (Formula 1).

d = p ² / δp (Formula 1)
A glass substrate for holding the polarization axis control unit is provided between the image generation region light shielding unit and the polarization axis control plate region light shielding unit, and these glass substrates are arranged at a certain distance from each other. ing. For this reason, the observer looks as if the image generation area light shielding part and the polarization axis control plate area light shielding part in front of each other overlap, and the image generation area light shielding part and the polarization axis control plate area light shielding part appear to be separated. Absent. For this reason, moire does not occur. However, when the observer observes a part away from the front, the image generation area light shielding part and the polarization axis control plate area light shielding part appear to be separated, that is, a moire is observed because of a deviation in the apparent pitch.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a stereoscopic image display optical member and a stereoscopic image display apparatus that reduce the occurrence of moire.

In order to achieve the above object, a first feature of the stereoscopic image display optical member according to the present invention is that a first polarization axis that is a polarization axis of a predetermined angle based on a first video signal input from the outside. A first modulated light generation region that generates and emits first modulated light by optically modulating the linearly polarized light, and linearly polarized light having the first polarization axis based on a second video signal input from the outside. Of the first modulated light and the second modulated light emitted from the image generation unit having a second modulated light generation region that emits light and generates second modulated light and emits the second modulated light, A polarizing plate that transmits and emits the first modulated polarized light and the second modulated polarized light that are linearly polarized light of the second polarization axis having an angle different from the polarization axis of
Corresponding to the position of the first modulated light generation region in the image generation unit, when the first modulated polarized light emitted from the polarizing plate is incident, the polarization axis of the first modulated polarized light is set to the third polarization axis. Corresponding to the position of the second modulated light generation region in the image generation unit, and the second modulated polarized light emitted from the polarizing plate corresponding to the position of the second modulated light generation region in the image generation unit. The second polarization region that is polarized so that the polarization axis of the second modulated polarization becomes a fourth polarization axis different from the third polarization axis and is emitted as the fourth modulated polarization, A polarization axis control plate provided at a boundary between the polarization region and the second polarization region and having a light shielding unit that shields incident light, and the light shielding unit transmits a part of the incident light. The permeable member is added.

  In order to achieve the above object, a second feature of the optical member for stereoscopic image display according to the present invention is that the size of the light transmissive member added to the light shielding portion in the film thickness direction is the film thickness of the light shielding portion. It is in the following.

  In order to achieve the above object, a third feature of the optical member for stereoscopic image display according to the present invention is that the light transmissive member added to the light shielding portion is a sphere.

  In order to achieve the above object, the fourth feature of the optical member for stereoscopic image display according to the present invention is that the addition ratio of the light transmissive member added to the light shielding portion is 20 to 50 (vol%). is there.

  In order to achieve the above object, a first feature of a stereoscopic image display device according to the present invention is a linearly polarized light that transmits a light source and a first linearly polarized light that is the first polarization axis of light emitted from the light source. A first modulation light generation region, a first modulation light generation region, and the first linearly polarized light emitted from the linearly polarized light generation unit is optically modulated when the first linear polarization is incident; 5. The stereoscopic image display optical member according to claim 1, wherein the image generation unit emits the modulated polarized light and the second modulated polarized light, and the first optical axis in the polarization axis control plate. An image generated by the third modulated polarized light exiting the polarization region is a right-eye image, and an image generated by the fourth modulated polarized light exiting the second polarization region is a left-eye image. .

  According to the three-dimensional image display optical member and the three-dimensional image display device of the present invention, it is possible to reduce the occurrence of moire.

1 is an exploded perspective view of a stereoscopic video display apparatus according to Embodiment 1 of the present invention. It is a perspective view which shows another form of the polarization-axis control board of the three-dimensional video display apparatus concerning Example 1 of this invention. It is the schematic which shows the use condition of the stereoscopic video display apparatus which concerns on Example 1 of this invention. It is a top view which expands and shows a part of video production | generation part with which the three-dimensional video display apparatus which concerns on Example 1 of this invention is provided. It is sectional drawing which showed an example of the cross section of a video production | generation part and a polarization axis control board in case the image production | generation area | region light shielding part and the polarization axis control board area | region light shielding part are not formed. FIG. 4 is a cross-sectional view illustrating an example of a cross section of an image generation unit and a polarization axis control plate provided in a stereoscopic image display apparatus according to an embodiment of the present invention. (A) is sectional drawing of the polarization-axis control board area | region light shielding part with which the three-dimensional video display apparatus which concerns on Example 1 of this invention is equipped, (b) is the stereoscopic video display apparatus which concerns on Example 1 of this invention. It is the figure which showed typically the optical film thickness in the cross section of (a) of the polarization axis control board area light-shielding part with which it is equipped, (c) is the polarization axis with which the three-dimensional image display apparatus which concerns on Example 1 of this invention is equipped. It is a top view of a control board area light-shielding part. (A) is sectional drawing of Experimental example 3 of the polarization axis control board area | region light shielding part with which the three-dimensional-image display apparatus which concerns on Example 1 of this invention is equipped, (b) is the three-dimensional which concerns on Example 1 of this invention. It is the figure of Experimental example 3 which showed typically the optical film thickness in the cross section of (a) of the polarization axis control board area | region light shielding part with which an image display apparatus is equipped, (c) concerns on Example 1 of this invention. It is a top view of Experimental example 3 of the polarization axis control board area | region light shielding part with which a three-dimensional video display apparatus is provided. In the stereoscopic image display apparatus according to Example 1 of the present invention, the results of moire evaluation and crosstalk evaluation for the experimental example and the comparative example in which the experiment was performed by changing the size and addition rate of the microbeads added to the light shielding portion. FIG. It is a perspective view which shows another form of the polarization-axis control board of the three-dimensional video display apparatus concerning Example 1 of this invention. It is a perspective view which shows another form of the polarization-axis control board of the three-dimensional video display apparatus concerning Example 1 of this invention. It is a disassembled perspective view of the three-dimensional-video display apparatus which concerns on Example 2 of this invention. It is the block diagram which showed the structure of the three-dimensional video display apparatus concerning Example 3 of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an exploded perspective view of a stereoscopic image display apparatus 100 according to Embodiment 1 of the present invention.

  The stereoscopic image display apparatus 100 includes a light source 120, an image display unit 130, and a polarization axis control plate (stereoscopic image display optical member) 180 in the order shown in FIG. 1, and these are accommodated in a casing (not shown). Yes. The image display unit 130 includes a polarizing plate (linearly polarized light generating unit) 150, an image generating unit 160 and a polarizing plate 170. When a viewer who will be described later observes a stereoscopic video displayed on the stereoscopic video display device 100, the observer is from the direction of the arrow X1 shown in FIG. 1 (from the right side of the polarization axis control plate 180 in FIG. 1). Observe.

  The light source 120 is disposed on the farthest side of the stereoscopic video display device 100 as viewed from the observer, and is in a state where the stereoscopic video display device 100 is used (hereinafter abbreviated as “usage state of the stereoscopic video display device 100”). 2, white non-polarized light is emitted toward one surface of the polarizing plate 150. In the first embodiment of the present invention, a surface light source is used as the light source 120, but a combination of a point light source and a condenser lens may be used instead of the surface light source. An example of this condensing lens is a Fresnel lens sheet.

  The polarizing plate 150 is disposed on the light source 120 side of the image generation unit 160. The polarizing plate 150 has a transmission axis and an absorption axis orthogonal to the transmission axis. When non-polarized light emitted from the light source 120 enters, the polarizing plate 150 transmits and absorbs light having a polarization axis parallel to the transmission axis. Blocks light with a polarization axis parallel to the axis. Here, the polarization axis is the vibration direction of the electric field in the light, and the transmission axis in the polarizing plate 150 is when the observer views the stereoscopic image display device 100 as indicated by an arrow Y1 in FIG. It has an inclination of 45 degrees from the horizontal direction to the upper right direction and the lower left direction. Therefore, the light emitted from the polarizing plate 150 becomes linearly polarized light having an inclination of 45 degrees from the horizontal direction.

  The video generation unit 160 includes pixels corresponding to red light, green light, and blue light, respectively. In addition, the video generation unit 160 includes a right-eye video generation area 162 including a plurality of pixels and a left-eye video generation area 164 including a plurality of pixels different from the right-eye video generation area 162. The image generation unit 160 optically modulates incident light from a liquid crystal display element or the like based on an image signal input from the outside. As shown in FIG. 1, the right-eye video generation area 162 and the left-eye video generation area 164 are areas in which the video generation section 160 is horizontally divided, and a plurality of right-eye video generation areas 162 and left-eye video generation areas are generated. Regions 164 are staggered in the vertical direction.

  In the usage state of the stereoscopic video display device 100, the right-eye video signal is generated in the right-eye video generation area 162 and the left-eye video generation area 164 of the video generation unit 160 by the right-eye video signal and the left-eye video signal supplied from the outside. And a left-eye video is generated. When a right-eye image is generated in the right-eye image generation area 162 and a part of the light transmitted through the polarizing plate 150 enters the right-eye image generation area 162, the right-eye image signal is modulated based on the right-eye image signal. From the video image generation area 162, video light of the right-eye video (hereinafter abbreviated as “right-eye video light”) is emitted. In addition, when a left-eye image is generated in the left-eye image generation region 164 and another part of the light transmitted through the polarizing plate 150 is incident on the left-eye image generation region 164, the left-eye image signal is generated based on the left-eye image signal. Light-modulated, left-eye image generation region 164 emits left-eye image light (hereinafter abbreviated as “left-eye image light”). Here, the right-eye image light emitted from the right-eye image generation region 162 and the left-eye image light emitted from the left-eye image generation region 164 are respectively light-modulated based on the image signal in the image light, and each has a polarization axis. Rotate. Further, in order to reduce the color mixture of red light, green light, and blue light, a light shielding portion called a black matrix is provided at the boundary portion of each pixel of the video generation unit 160. Further, a video generation area light-shielding portion 163 that is a strip-shaped black stripe is formed at the boundary between the right-eye video generation area 162 and the left-eye video generation area 164 in the black matrix.

  The polarizing plate 170 is disposed on the viewer side in the video generation unit 160. When the right-eye video light that has passed through the right-eye video generation region 162 and the left-eye video light that has passed through the left-eye video generation region 164 are incident on the polarizing plate 170, the polarization axis component of these components. The polarization component parallel to the transmission axis is transmitted, and the polarization component whose polarization axis is parallel to the absorption axis is blocked. Here, the transmission axis of the polarizing plate 170 has an inclination of 45 degrees from the horizontal direction to the upper left direction and the lower right direction when the observer views the stereoscopic image display device 100 as indicated by an arrow Y2 in FIG. . Accordingly, the light emitted from the polarizing plate 170 is linearly polarized light that is orthogonal to the light emitted from the polarizing plate 150 and has an inclination of 45 degrees from the horizontal direction. In addition, the direction of the transmission axis in the polarizing plate 170 is substantially matched with the directions of the polarization axes of the right-eye video light and the left-eye video light emitted from the video generation unit 160, thereby improving the luminance of the stereoscopic video display device 100. Can do.

  The polarization axis control plate 180 includes a substrate 184 and a first polarization region 181 and a second polarization region 182 formed on the substrate 184. The positions and sizes of the first polarization region 181 and the second polarization region 182 on the polarization axis control plate 180 are as shown in FIG. 1, and the right-eye image generation region 162 and the left-eye image generation region 164 of the image generation unit 160. Corresponds to the position and size. Therefore, in the usage state of the stereoscopic image display device 100, the right-eye image light transmitted through the right-eye image generation region 162 is incident on the first polarization region 181 and the left-eye image generation region is input to the second polarization region 182. The image light for the left eye that has passed through 164 enters.

  The first polarizing region 181 transmits the incident right eye image light as it is without rotating the polarization axis thereof. On the other hand, the second polarization region 182 rotates the polarization axis of the incident left-eye image light by 90 degrees in a direction orthogonal to the polarization axis of the right-eye image light incident on the first polarization region 181. Therefore, the polarization axis of the right-eye image light transmitted through the first polarization region 181 and the polarization axis of the left-eye image light transmitted through the second polarization region 182 are as shown by arrows Y3 and Y4 in FIG. The directions are orthogonal to each other. In FIG. 1, arrows Y3 and Y4 shown in the first polarization region 181 and the second polarization region 182 of the polarization axis control plate 180 indicate the directions of the polarization axes of the polarized light passing through the polarization regions.

  In the polarization axis control plate 180, a plate-like member such as a transparent glass having a low birefringence or a resin having a low birefringence, or a birefringence is provided on the substrate 184 so as not to change the direction of the polarization axis of the incident image light. A film-like member having a low value is used. The first polarizing region 181 transmits light without changing the direction of the polarization axis of the incident video light for the right eye, so that light is transmitted without providing anything on the substrate 184 or glass having low birefringence. Or a member such as a resin, or a polarizing plate having a polarization state similar to that of the polarizing plate 170 is used. For the second polarizing region 182, for example, a half-wave plate made of a birefringent material having the property of rotating the direction of the polarization axis of the incident left-eye image light by 90 degrees is used. As a result, the direction of the polarization axis of the right-eye image light emitted from the polarization axis control plate 180 is orthogonal to the direction of the polarization axis of the left-eye image light.

  As another form of the polarization axis control plate 180, a structure having a substrate 184 as shown in FIG. 2 and a second polarization region 182 formed on the substrate 184 may be used.

  Further, a band-shaped polarization axis control plate region light-shielding unit 183 is provided on the side of the image display unit 130 at the boundary between the first polarization region 181 and the second polarization region 182 on the surface of the polarization axis control plate 180 facing the image display unit 130. Is provided. By providing such a polarization axis control plate region light-shielding portion 183, the left eye image light that should enter the second polarization region 182 adjacent to the first polarization region 181 of the polarization axis control plate 180 exceeds the boundary. Thus, the image light incident on the first polarization region 181 can be absorbed and blocked. Similarly, of the right-eye image light that should be incident on the first polarization region 181 adjacent to the second polarization region 182 of the polarization axis control plate 180, the image that enters the second polarization region 182 beyond the boundary. Can absorb and block light. Therefore, crosstalk is less likely to occur in the right-eye video light and the left-eye video light emitted from the stereoscopic video display device 100. Details of the crosstalk will be described later.

  In addition, the stereoscopic image display apparatus 100 is closer to the observer side than the polarization axis control plate 180 (on the right side of the polarization axis control plate 180 in FIG. 1), and the first polarization region 181 and the second polarization of the polarization axis control plate 180. You may have the diffuser which diffuses the image light for right eyes and the image light for left eyes which permeate | transmitted the area | region 182 to at least one direction of a horizontal direction or a perpendicular direction. For such a diffuser plate, for example, a lenticular lens sheet in which a plurality of cylindrically shaped convex lenses (cylindrical lenses) extending in the horizontal direction or the vertical direction is used, or a lens array sheet in which a plurality of convex lenses are arranged in a planar shape is used. It is done.

  FIG. 3 is a schematic diagram illustrating a usage state of the stereoscopic video display device 100.

  When observing a stereoscopic image with the stereoscopic image display device 100, the observer 500 puts the right eye image light and the left eye image light projected from the stereoscopic image display device 100 through polarized glasses 200 as shown in FIG. 3. Observe. In the polarizing glasses 200, when the observer 500 puts on the polarizing glasses 200, a right-eye image transmission unit 232 is disposed at a position corresponding to the right eye 512 side of the observer 500, and a left-eye image transmission is performed at a position corresponding to the left eye 514 side. A part 234 is arranged. The right-eye image transmission unit 232 and the left-eye image transmission unit 234 are polarization lenses having different transmission axis directions, and are fixed to the frame of the polarizing glasses 200.

  The right-eye image transmission unit 232 is a polarizing plate having the same transmission axis as the right-eye image light transmitted through the first polarizing region 181 and the absorption axis being orthogonal to the transmission axis. The left-eye image transmission unit 234 is a polarizing plate having the same transmission axis as the left-eye image light transmitted through the second polarization region 182 and the absorption axis orthogonal to the transmission axis. For the right-eye image transmission unit 232 and the left-eye image transmission unit 234, for example, a polarizing lens to which a polarizing film obtained by uniaxially stretching a film impregnated with a dichroic dye is attached.

  When the observer 500 observes a stereoscopic image with the stereoscopic image display device 100, the observer 500 is within a range in which the right-eye image light transmitted through the first polarization region 181 and the left-eye image light transmitted through the second polarization region 182 are emitted. By observing the stereoscopic image display apparatus 100 with the polarizing glasses 200, the right eye 512 can observe only the right eye image included in the right eye image light, and the left eye 514 includes the left eye included in the left eye image light. You can observe only the video. Therefore, the viewer 500 can recognize these right-eye video and left-eye video as stereoscopic video.

  FIG. 4 is an enlarged plan view showing a part of the video generation unit 160.

  As shown in FIG. 4, the right-eye video generation region 162 and the left-eye video generation region 164 of the video generation unit 160 are each divided into a plurality of small cells in the horizontal direction, and each of these cells is red. A display pixel 361, a green display pixel 362, and a blue display pixel 363 are provided.

  Note that, in the right-eye video generation region 162 and the left-eye video generation region 164 of the video generation unit 160, for example, a red display pixel 361, a green display pixel 362, and a blue display pixel 363 are repeatedly arranged in this order in the horizontal direction.

  In addition, a video generation region light shielding unit 163 that is a black stripe is formed at the boundary portion of each pixel including the boundary portion between the right eye video generation region 162 and the left eye video generation region 164 of the video generation unit 160.

  Here, crosstalk will be described.

  FIG. 5 is a cross-sectional view illustrating an example of a cross section of the image generation unit 160 and the polarization axis control plate 180 when the image generation region light shielding unit 163 and the polarization axis control plate region light shielding unit 183 are not formed.

  As shown in FIG. 5, the polarization axis control plate 180 is arranged such that the first polarization region 181 is positioned in front of the right eye image generation region 162 and the second polarization region 182 is in front of the left eye image generation region 164. Is positioned on the near side of the video generation unit 160 as viewed from the observer 500.

  Then, right-eye image light is emitted from the right-eye image generation area 162, and the emitted right-eye image light passes through the first polarization area 181 and reaches the observer 500. On the other hand, left-eye image light is emitted from the left-eye image generation region 164, and the emitted left-eye image light is incident on the second polarization region 182 and the polarization vibration direction is rotated by 90 ° to the observer 500. To reach.

  As described above, in order to display the right-eye video and the left-eye video in the stereoscopic video display device 100, the right-eye video light emitted from the right-eye video generation region 162 is incident on the first polarization region 181; The left-eye image light emitted from the left-eye image generation region 164 needs to be incident on the second polarization region 182.

  For example, when the right-eye image light emitted from the right-eye image generation region 162 is incident on the second polarization region 182, the polarization vibration direction is rotated by 90 ° and is captured by the left-eye image transmission unit 234 of the viewer 500. It will be the video that will be. Of course, this video is different from the original left-eye video, so that the video captured by the observer 500 may become unclear, and the three-dimensional effect may become unclear.

  However, in the related art, the right-eye video light and the left-eye video light emitted from the video generation unit 160 are accurately input to the first polarization region 181 and the second polarization region 182 respectively. It was very difficult to arrange the polarization axis control plate 180.

  In order to obtain a clear image, it is better that the right-eye image generation area 162 and the left-eye image generation area 164 are dense (thin), but in this case, the right-eye image generation area 162 and the left-eye image generation area The first polarization region 181 and the second polarization region 182 are accurately arranged in front of the image generation unit 160 in which 164 is densely arranged so as to correspond to the right-eye image generation region 162 and the left-eye image generation region 164. It was extremely difficult. Specifically, the general first polarizing region 181 and the second polarizing region 182 are each an ultrathin line having a width of about 200 μm, and are accurately arranged at a level of several tens of μm so that the positional deviation is less than 5%. It is very difficult.

  Further, since the right-eye image light emitted from the right-eye image generation region 162 and the left-eye image light emitted from the left-eye image generation region 164 are not completely parallel light, for example, as shown in FIG. In addition, part of the left-eye video light emitted from the vicinity of the upper end of the left-eye video generation region 164 may be incident on the first polarization region 181 (arrow 10 shown in FIG. 5).

  Furthermore, the left-eye image light emitted from the left-eye image generation region 164 may once enter the second polarization region 182 and then enter the first polarization region 181 (arrow 11 shown in FIG. 5). . This phenomenon is generally called a crosstalk phenomenon. In this case, the vibration direction of the polarization of the left-eye image light indicated by the arrow 11 is rotated within a range of 0 to 90 °. For example, when the left-eye image light is rotated 45 °, the left-eye image light is converted into the right-eye image light. Each of the images passes through the transmission unit 232 and the left-eye image transmission unit 234 by 50%. Also in this respect, the image captured by the observer 500 becomes unclear and the stereoscopic effect becomes unclear. .

  Therefore, the stereoscopic image display apparatus 100 according to the first embodiment of the present invention is configured to include the polarization axis control plate region light shielding unit 183 in the polarization axis control plate 180.

  FIG. 6 is a cross-sectional view illustrating an example of a cross section of the image generation unit 160 and the polarization axis control plate 180 included in the stereoscopic image display apparatus 100 according to the first embodiment of the present invention.

  As shown in FIG. 6, the video generation unit 160 includes a video generation unit 160 in which a right-eye video generation region 162 and a left-eye video generation region 164 are alternately arranged. A video generation area light-shielding portion 163 that is a black stripe is formed at the boundary between the video generation area 162 and the left-eye video generation area 164.

  Further, in the polarization axis control plate 180, a band-shaped polarization axis control plate region light shielding portion 183 is formed at the boundary between the second polarization region 182 and the first polarization region 181 in order to reduce crosstalk.

  The image generation region light shielding portion 163 and the polarization axis control plate region light shielding portion 183 are formed using a printing method, and the coating material used here is an ultraviolet curable resin or a thermosetting resin to which a black dye is added. Usually, the polarization axis control plate region light-shielding portion 183 is formed as a black belt. Here, letterpress printing, planographic printing, intaglio printing, stencil printing, screen printing, offset printing, and the like can be used as the printing method.

  As a result, among the image light for the left eye that should enter the second polarization region 182 adjacent to the first polarization region 181 of the polarization axis control plate 180, the image light that enters the first polarization region 181 beyond the boundary is absorbed. Can be blocked.

  Similarly, among the right-eye video light that should enter the first polarization region 181 adjacent to the second polarization region 182 of the polarization axis control plate 180, the image light that enters the second polarization region 182 beyond the boundary. Can be absorbed and blocked. Therefore, crosstalk is less likely to occur in the right-eye video light and the left-eye video light emitted from the stereoscopic video display device 100.

  Therefore, when the observer 500 observes a stereoscopic image with the stereoscopic image display apparatus 100, the range in which the right-eye image light transmitted through the first polarization region 181 and the left-eye image light transmitted through the second polarization region 182 are emitted. , By observing the stereoscopic image display device 100 with polarized glasses 200, the right eye can observe only the right eye image included in the right eye image light, and the left eye includes the left eye included in the left eye image light. You can observe only the video. Thereby, the observer 500 can recognize these right-eye video and left-eye video as stereoscopic video.

  The pitch between the image generation region light shielding unit 163 and the polarization axis control plate region light shielding unit 183 is approximate, and moire is likely to occur. Therefore, the polarization axis control plate region light shielding portion 183 of the polarization axis control plate 180 provided in the stereoscopic image display apparatus 100 according to the first embodiment of the present invention is a spherical light transmissive member (hereinafter referred to as microbead) in the paint. Is added to form a predetermined shape, thereby reducing the occurrence of moire. The microbeads used here are fine spheres or substantially spherical particles having a material particle size of about 1 to 1000 μm made of an acrylic material or a silicon material, and transmit a predetermined amount of light. The microbeads are not necessarily spherical, but may be cylindrical or indefinite.

  Here, since the microbeads are contained in the paint and are applied by the printing method described above, the positions of the microbeads can be randomly arranged. For this reason, the amount of transmitted light and the distribution of the transmitted light amount can be made random, and the occurrence of moire can be reduced.

  FIG. 7A is a cross-sectional view of the polarization axis control plate region light shielding portion 183 included in the stereoscopic image display apparatus 100 according to the first embodiment of the present invention, and FIG. 7B is a diagram illustrating the first embodiment of the present invention. It is the figure which showed typically the optical film thickness in the cross section of Fig.7 (a) of the polarization-axis control board area | region light-shielding part 183 with which the three-dimensional image display apparatus 100 concerned is equipped, FIG.7 (c) is implementation of this invention. 6 is a plan view of a polarization axis control plate region light shielding unit 183 included in the stereoscopic video display apparatus 100 according to Example 1. FIG.

  As shown in FIGS. 7A and 7C, the polarization axis control plate region light-shielding portion 183 is formed of microbeads randomly on the light-shielding portion 183a formed of an ultraviolet curable resin or a thermosetting resin to which a black dye is added. 183b is added.

  Further, as shown in FIGS. 7A and 7C, since the light shielding portion 183a is formed with a film thickness d1 which is approximately the same as the diameter of the microbead 183b, a part of the microbead 183b is part of the light shielding portion 183a. Since it appears on the surface, the image light is transmitted, and the transmittance is random depending on the incident position.

  In the diagram shown in FIG. 7B, in the cross section of FIG. 7A of the polarization axis control plate region light shielding portion 183, the optical film becomes thicker as the image light shielding rate is higher, that is, the transmittance is lower. The optical film thickness od1 which is the thickness is shown.

  As shown in FIG. 7 (b), since the micro-beads 183b are randomly added, the optically uneven shape is randomly formed. Therefore, regions having different transmittances are formed on the surface of the light shielding portion 183a. Will appear randomly. As a result, the moire between the image generation region light-shielding portion 163 reduces the contrast between the black portion and the white portion and makes it difficult to see the moire.

  Hereinafter, experimental examples and comparative examples in which an experiment for investigating changes in crosstalk and moire by changing the size and addition rate of the microbeads 183b added to the light shielding portion 183a will be described.

<Experimental example 1>
In Experimental Example 1, a black pigment and microbeads 183b having a diameter of 5 (μm) were added to an ultraviolet curable resin, and the film thickness (d1 in FIG. 7A) was changed to 5 (μm) and width by the printing method described above. A polarization axis control plate region light-shielding portion 183 (W1 in FIG. 7B) of 135 (μm) was formed. At this time, the pitch of the polarization axis control plate region light shielding portions 183 is 270 (μm). In addition, the pitch of the image generation region light blocking portions 163 is also 270 (μm).

  Then, the addition rate of the microbeads 183b was changed in a volume ratio of 10 to 70 (vol%), and crosstalk (the ratio of the left-eye image included in the right-eye image) and the change in moire were investigated.

<Experimental example 2>
In Experimental Example 2, a black pigment and microbeads 183b having a diameter of 10 (μm) were added to an ultraviolet curable resin, and the film thickness (d1 in FIG. 7A) was set to 10 (μm) and width by the printing method described above. A polarization axis control plate region light-shielding portion 183 (W1 in FIG. 7B) of 135 (μm) was formed. At this time, the pitch of the polarization axis control plate region light shielding portions 183 is 270 (μm). In addition, the pitch of the image generation region light blocking portions 163 is also 270 (μm).

  Then, the addition rate of the microbeads 183b was changed in a volume ratio of 10 to 70 (vol%), and crosstalk (the ratio of the left-eye image included in the right-eye image) and the change in moire were investigated.

<Experimental example 3>
FIG. 8A is a cross-sectional view of Experimental Example 3 of the polarization axis control plate region light shielding portion 183 provided in the stereoscopic image display apparatus 100 according to Example 1 of the present invention, and FIG. FIG. 8 is a diagram of Experimental Example 3 schematically showing the optical film thickness in the cross section of FIG. 8A of the polarization axis control plate region light shielding portion 183 included in the stereoscopic image display apparatus 100 according to Example 1; c) is a plan view of Experimental Example 3 of the polarization axis control plate region light-shielding portion 183 included in the stereoscopic image display apparatus 100 according to Embodiment 1 of the present invention.

  As shown in FIGS. 8A and 8C, the polarization axis control plate region light-shielding portion 183 has various randomly added light-shielding portions 183a formed of an ultraviolet curable resin or a thermosetting resin to which a black dye is added. Microbeads 183b with a diameter are added.

  Further, as shown in FIGS. 8A and 8C, since the microbeads 183b having various diameters are added to the light-shielding portion 183a formed with the film thickness d2, the transmittance of the image light is further incident. It becomes random depending on the position.

  In the diagram shown in FIG. 8B, in the cross section of FIG. 8A of the polarization axis control plate region light shielding portion 183 of Experimental Example 3, the higher the image light shielding rate, that is, the lower the transmittance, the thicker the light. An optical film thickness od2 that is an optical film thickness is shown.

  As shown in FIG. 8B, since the microbeads 183b having different diameters are randomly added, the size and shape of the optical irregularities are more randomly formed, so that the light-shielding portion 183a is transmissive. Regions with different rates will appear randomly. As a result, the moire between the image generation region light-shielding portion 163 reduces the contrast between the black portion and the white portion, and makes the moire less visible.

  In Experimental Example 3, a black pigment, microbeads 183b having various diameters of 1 to 15 (μm) were added to an ultraviolet curable resin, and the film thickness (d2 in FIG. 8A) was changed by the above-described printing method. A polarization axis control plate region light-shielding portion 183 having a thickness of 7 (μm) and a width (W1 in FIG. 7B) of 135 (μm) was formed. At this time, the pitch of the polarization axis control plate region light shielding portions 183 is 270 (μm). In addition, the pitch of the image generation region light blocking portions 163 is also 270 (μm).

  And the change of the crosstalk (ratio of the image | video for left eyes contained in the image | video for right eyes) and a moire in 30% (vol%) of the addition rate of the microbead 183b was investigated.

<Comparative Example 1>
In Comparative Example 1, the polarization axis control plate region light shielding portion was formed under the same conditions as in Example 1 except that the microbead 183b was not added.

<Comparative example 2>
In Comparative Example 2, the polarization axis control plate region light shielding portion was formed under the same conditions as in Example 2 except that the microbead 183b was not added.

<Experimental result>
FIG. 9 shows a moiré pattern for an experimental example and a comparative example in which the experiment was performed by changing the size and addition rate of the microbeads 183b added to the light-shielding portion 183a in the stereoscopic image display apparatus 100 according to Example 1 of the present invention. It is the figure which showed the result of evaluation and crosstalk evaluation. It is assumed that the moire evaluation is a five-level evaluation. In the evaluation 1, the moire is not observed, the moire becomes clear as the numerical value increases, and the evaluation 5 is observed most clearly. Specifically, when the moire evaluation is 4 or more, the display image is greatly deteriorated due to moire, which causes a practical problem as a video display device. The crosstalk evaluation is “O” if the ratio of the left-eye video light included in the right-eye video light is 10% or less, and therefore, the video quality is not a problem. When it exceeded, it was set as “x”.

  As shown in FIG. 9, in Comparative Example 1 and Comparative Example 2, although there is no problem with crosstalk, moire occurs.

  On the other hand, in Experimental Example 1 and Experimental Example 2, the region where the crosstalk evaluation result, which is a practical level as a video display device, is ◯ and the moire evaluation result is 3 or less is added with microbead 183b. The rate was found to be 20-50 (vol%). Furthermore, when the addition rate of the microbead 183b is in the range of 30 to 40 (vol%), it was found that moire is less visible and crosstalk is a better result without problems.

  Also in Experimental Example 3, it can be seen that the addition rate of microbead 183b is 30 (vol%), and that moire is less visible than Comparative Examples 1 and 2.

  If microbeads having different diameters are added, the randomness of the optical unevenness is increased, so the effect of reducing moire is considered to be greater.

  In addition, in Experimental Example 1 and Experimental Example 2, the moire at the volume ratio of 70 (vol%) in the content of the microbead 183b is not clearer than the moire at 60 (vol%). This is because the image becomes unclear and the interference with the image generation region light shielding portion 163 is reduced.

  As described above, according to the stereoscopic image display device 100 according to the first embodiment of the present invention, the first polarizing region 181, the second polarizing region 182, and the boundary between the first polarizing region 181 and the second polarizing region 182. And the polarization axis control plate region light shielding portion 183 to which the microbeads 183b are added. Therefore, regions having different transmittances appear at random, and the moire between the image generation region light shielding portion 163 is a black portion and a white portion. Contrast can be reduced, and the occurrence of moire can be reduced.

  In Example 1 of the present invention, a stereoscopic image display including a polarization axis control plate region light shielding unit 183 to which spherical micro beads 183b provided at the boundary between the first polarization region 181 and the second polarization region 182 is added. Although the apparatus 100 has been described as an example, the microbead 183b is not limited to a sphere, and may be formed of light transmissive members having various shapes and sizes.

  Further, in the first embodiment of the present invention, the right-eye image generation area 162 and the left-eye image generation area 164 of the image generation section 160 are described as areas in which the image generation section 160 is divided in the horizontal direction as shown in FIG. However, as shown in FIG. 10, the video generation unit 160 may be a region partitioned in the vertical direction. In that case, it is necessary to change the drive circuit of the image generation unit 160 and to separate the first polarization region 181 and the second polarization region 182 in the polarization axis control plate 180 in the vertical direction.

  Further, the right-eye image generation area 162 and the left-eye image generation area 164 of the image generation unit 160 are divided into a lattice by dividing the drive circuit of the image generation unit 160 in the horizontal direction and the vertical direction as shown in FIG. You may comprise in a shape. In this case, the polarization axis control plate 180 also needs to be formed in a lattice shape in accordance with the image generation unit 160.

  In Example 1 of the present invention, when the right-eye video light and the left-eye video light are respectively incident on the first polarizing region 181 and the second polarizing region 182, the incident right-eye video light and left-eye video light are polarized. Although the stereoscopic image display apparatus 100 including the polarization axis control plate 180 that emits linearly polarized light whose axes are orthogonal to each other has been described as an example, the present invention is not limited thereto.

  In the second embodiment of the present invention, when the right-eye video light and the left-eye video light are respectively incident on the first polarization region 181 and the second polarization region 182, the incident right-eye video light and left-eye video light are polarized. The stereoscopic image display apparatus 102 including a polarization axis control plate that emits circularly polarized light whose axis rotation directions are opposite to each other will be described as an example.

  FIG. 12 is an exploded perspective view of the stereoscopic image display apparatus 101 according to the second embodiment of the present invention.

  In the stereoscopic video display apparatus 101 shown in FIG. 12, the same components as those in the stereoscopic video display apparatus 100 shown in FIG.

  As shown in FIG. 12, the stereoscopic video display device 101 includes a polarization axis control plate 185 instead of the polarization axis control plate 180 of the stereoscopic video display device 100. The polarization axis control plate 185 includes a substrate 184 and a first polarization region 186 and a second polarization region 187 formed on the substrate 184. The positions and sizes of the first polarization region 186 and the second polarization region 187 in the polarization axis control plate 185 are similar to the positions and sizes of the first polarization region 181 and the second polarization region 182 in the polarization axis control plate 180, respectively. This corresponds to the positions and sizes of the right-eye video generation area 162 and the left-eye video generation area 164 of the video generation unit 160. Therefore, in the usage state of the stereoscopic image display apparatus 101, the right-eye image light transmitted through the right-eye image generation region 162 is incident on the first polarization region 186, and the left-eye image is incident on the second polarization region 187. The left-eye image light that has passed through the generation region 164 enters.

  The first polarizing region 186 emits the incident right-eye video light as clockwise circularly polarized light. The second polarization region 187 emits the incident left-eye image light as counterclockwise circularly polarized light. Note that arrows Y5 and Y6 of the polarization axis control plate 185 in FIG. 12 indicate the rotation direction of the polarized light that has passed through the polarization axis control plate 185. For the first polarizing region 186, for example, a quarter wavelength plate whose optical axis is in the horizontal direction is used, and for the second polarizing region 187, for example, a quarter wavelength plate whose optical axis is in the vertical direction is used. The first polarization region 186 and the second polarization region 187 of the polarization axis control plate 185 are each divided into a plurality of small cells in the horizontal direction in the same manner as the first polarization region 181 and the second polarization region 182 of the polarization axis control plate 180. Has been.

  When observing the stereoscopic image display apparatus 101 provided with the polarization axis control plate 185, the observer 500 is polarized glasses in which a quarter wavelength plate and a polarizing lens are arranged at a position corresponding to the right eye 512 and a position corresponding to the left eye 514, respectively. To observe. In this polarized glasses, the quarter-wave plate disposed at the position corresponding to the right eye 512 side of the viewer 500 has a horizontal optical axis and is disposed at the position corresponding to the left eye 514 side of the viewer 500. Is the vertical direction of the optical axis.

  Further, both the polarizing lens arranged at the position corresponding to the right eye 512 side of the observer 500 and the polarizing lens arranged at the position corresponding to the left eye 514 side of the observer 500 both have a transmission axis direction right when viewed from the observer 500. The angle is 45 degrees and the direction of the absorption axis is perpendicular to the direction of the transmission axis.

  When the viewer 500 observes the stereoscopic image display apparatus 101 wearing the above polarizing glasses, on the right eye 512 side of the viewer 500, when the circularly polarized light whose polarization axis is clockwise when viewed from the viewer 500 is incident, The circularly polarized light is converted into linearly polarized light having an angle of 45 degrees to the right by a ¼ wavelength plate whose horizontal axis is the horizontal direction, and then transmitted through the polarizing lens and observed by the right eye 512 of the observer 500.

  On the left eye 514 side of the observer 500, when circularly polarized light whose polarization axis is counterclockwise when viewed from the observer 500 is incident, the circularly polarized light is reflected by the quarter wavelength plate whose optical axis is the vertical direction. After being converted into linearly polarized light having an oblique right angle of 45 degrees, the light passes through the polarizing lens and is observed by the left eye 514 of the observer 500.

  Thus, by observing the stereoscopic image display apparatus 101 with the polarizing glasses, the right eye 512 can observe only the right eye image included in the right eye image light, and the left eye 514 can convert the left eye image light. Only the left-eye image included can be observed. Therefore, the viewer 500 can recognize these right-eye video and left-eye video as stereoscopic video.

  Then, according to the stereoscopic image display apparatus 101 according to the second embodiment of the present invention, similarly to the stereoscopic image display apparatus 100 according to the first embodiment of the present invention, the first polarization region 181, the second polarization region 182, Since it has the polarization axis control plate region light-shielding portion 183 to which the microbeads 183b provided at the boundary between the first polarizing region 181 and the second polarizing region 182 are added, regions having different transmittances appear at random, and the image The moire between the generation region light-shielding portion 163 reduces the contrast between the black portion and the white portion, and can reduce the occurrence of moire.

  In the stereoscopic image display apparatus 100 according to the first embodiment of the present invention, the position and size of the first polarization region 181 and the second polarization region 182 of the polarization axis control plate 180 are determined based on the right eye image generation region 162 of the image generation unit 160. In addition, although it is arranged so as to coincide with the position and size of the left-eye video generation region 164, the present invention is not limited to this.

  In the third embodiment of the present invention, the position and size of the first polarization region 181 and the second polarization region 182 of the polarization axis control plate 180 are for the right eye of the image generation unit 160 according to the distance to the viewer's position. The stereoscopic video display device 102 arranged so as to correspond to the positions and sizes of the video generation area 162 and the left-eye video generation area 164 will be described as an example.

  FIG. 13 is a configuration diagram illustrating the configuration of the stereoscopic video display apparatus 102 according to the third embodiment of the present invention. In the stereoscopic video display device 102 shown in FIG. 13, the same components as those in the stereoscopic video display device 100 shown in FIG.

  As shown in FIG. 13, the stereoscopic video display device 102 includes a polarization axis control plate 190 instead of the polarization axis control plate 180 of the stereoscopic video display device 100.

  The polarization axis control plate 190 includes a substrate 184 (not shown), a first polarization region 191 formed on the substrate 184, a second polarization region 192 (both not shown), a first polarization region 191 and a second polarization region. And a polarization axis control plate region light-shielding portion 193 to which microbeads 183b provided at the boundary portion of 192 are added.

  The polarization axis control plate 190 has a distance from the observer position P to the image generation unit 160 assumed from the screen size of the stereoscopic image display device 100 and a distance from the observer position P to the polarization axis control plate 190. Based on this, as viewed from the observer, the first polarization region 191, the second polarization region 192, and the polarization of the polarization axis control plate 190 so that the image generation region light shielding unit 163 and the polarization axis control plate region light shielding unit 193 overlap each other. An axis control plate area light-shielding portion 193 is disposed.

  Thus, according to the stereoscopic image display apparatus 102 according to the third embodiment of the present invention, when the observer observes at the position P, the image generation region light shielding unit and the polarization axis control plate region light shielding unit seem to overlap each other. Looks like. However, when the observer observes from the position P at a position close to or far from the stereoscopic image display device 100, the image generation region light shielding unit and the polarization axis control plate region light shielding unit appear to be shifted.

  According to the stereoscopic video display apparatus 102 according to the third embodiment of the present invention, even when such an observer observes at a position other than the position P, the same as the stereoscopic video display apparatus 100 according to the first embodiment of the present invention. A polarization axis control plate region light-shielding portion 183 to which a first polarizing region 181, a second polarizing region 182, and a microbead 183 b provided at the boundary between the first polarizing region 181 and the second polarizing region 182 are added. Therefore, regions having different transmittances appear at random, and the moire between the image generation region light-shielding portion 163 reduces the contrast between the black portion and the white portion, and the occurrence of moire can be reduced.

DESCRIPTION OF SYMBOLS 100,101,102 ... Three-dimensional video display apparatus 120 ... Light source 130 ... Video display part 150 ... Polarizing plate 160 ... Video generation part 162 ... Video generation area for right eyes 163 ... Video generation area light-shielding part 164 ... Video generation area for left eyes 170 ... Polarizing plates 180, 185, 190 ... Polarization axis control plates 181, 186, 191 ... First polarization regions 182, 187, 192 ... Second polarization regions 183, 193 ... Polarization axis control plate regions light shielding part 183a ... Light shielding part 183b ... Micro Bead 200 ... Polarized glasses

Claims (5)

Based on the first video signal input from the outside, the first modulated light that generates the first modulated light by optically modulating the linearly polarized light of the first polarization axis that is the polarization axis of a predetermined angle and emits the first modulated light A generation region, and a second modulated light generation region that generates and emits second modulated light by optically modulating linearly polarized light of the first polarization axis based on a second video signal input from the outside. Of the first modulated light and the second modulated light emitted from the image generating unit, the first modulated polarized light that is linearly polarized light having a second polarization axis having an angle different from the first polarization axis And a polarizing plate that transmits and emits the second modulated polarized light,
Corresponding to the position of the first modulated light generation region in the image generation unit, when the first modulated polarized light emitted from the polarizing plate is incident, the polarization axis of the first modulated polarized light is set to the third polarization axis. Corresponding to the position of the second modulated light generation region in the image generation unit, and the second modulated polarized light emitted from the polarizing plate corresponding to the position of the second modulated light generation region in the image generation unit. The second polarization region that is polarized so that the polarization axis of the second modulated polarization becomes a fourth polarization axis different from the third polarization axis and is emitted as the fourth modulated polarization, A polarization axis control plate having a light shielding portion that shields incident light provided at a boundary portion between the polarization region and the second polarization region;
With
The light-shielding part is added with a light-transmitting member that transmits a part of the incident light. The stereoscopic image display optical member according to claim 1, wherein a size of the light transmissive member added to the light shielding portion in a film thickness direction is equal to or less than a film thickness of the light shielding portion. The optical member for stereoscopic video display according to claim 1 or 2, wherein the light transmissive member added to the light shielding portion is a sphere. The optical member for stereoscopic video display according to any one of claims 1 to 3, wherein an addition ratio of the light transmissive member added to the light shielding portion is 20 to 50 (vol%). A light source;
A linearly polarized light generator that transmits the first linearly polarized light that is the first polarization axis of the light emitted from the light source;
A first modulated light generation region and a second modulated light generation region, wherein when the first linearly polarized light emitted from the linearly polarized light generation unit is incident, the first modulated polarized light and the first modulated polarized light; The image generation unit emitting the second modulated polarized light;
The optical member for stereoscopic image display according to any one of claims 1 to 4,
With
An image generated by the third modulation polarization emitted from the first polarization region on the polarization axis control plate is a right-eye image, and is generated by the fourth modulation polarization emitted from the second polarization region. A three-dimensional video device characterized in that the video is a left-eye video.

Images