JP2016212308A - Three-dimensional image displaying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional image displaying device that restrains unevenness of images.SOLUTION: A three-dimensional image displaying device 1 is equipped with multiple backlights 10 arranged on the same plane, multiple display panels 20 that display divided three-dimensional images and are so arranged on the same plane as to match the backlights 10, an expanded optical system 30 that has a prescribed spread angle and expands three-dimensional images displayed on the display panels 20, a diffuser panel 40 that has a prescribed diffusion angle and combines the divided three-dimensional images from the expanded optical system 30, and a displaying lens array 50. The working distance from the expanded optical system 30 to the diffuser panel 40 is not shorter than a preset distance.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a stereoscopic video display apparatus that displays a stereoscopic video.

Integral stereoscopic television is a 3D video system that does not require special glasses and enables stereoscopic viewing with the naked eye (for example, Patent Document 1). As shown in FIG. 16, a conventional integral solid TV 9 includes an image display panel P such as a liquid crystal panel, and a lens array L _A which is arranged in front of the image display panel P. The lens array L _A are those elements lens L _P are arrayed two-dimensionally. Further, corresponds and the element lenses L _P and the element image G, the element lenses L _P element image G is projected in the space, stereoscopic image Z is formed.

Japanese Patent No. 4741395 (FIGS. 22 to 24)

  In the conventional integral stereoscopic television 9, it is necessary to display a very large number of pixels on the image display panel P in order to improve the number of pixels, the viewing area, and the depth reproduction range of the stereoscopic video. However, at present, there is no image display panel P having a number of pixels exceeding the super high-definition, and it is difficult to improve the quality of the integral stereoscopic video by the single image display panel P. Therefore, in the integral 3D television 9, a technique for increasing the number of pixels using a plurality of image display panels P is required.

When the integral stereoscopic television 9 has a large number of pixels, there are the following problems.
If the plurality of image display panels P are arranged as they are, a bezel portion (frame) is present in each image display panel P. Therefore, a break in the displayed video occurs in the bezel portion, and a similar break is also generated in the reproduced stereoscopic video. Occurs. At present, it is difficult to manufacture the image display panel P having no bezel portion, so it is necessary to combine a plurality of display images so that there is no break.

For this purpose, an enlargement optical system (not shown) that introduces and enlarges the images displayed on the respective image display panels P is introduced. Specifically, the display image is enlarged by an enlargement optical system arranged in front of each image display panel P, and the enlargement images are combined by a diffusion plate (not shown) arranged at the imaging position. In this case, since the light spreads by enlarging the display image with the magnifying optical system, the light imaged on the diffusion plate has anisotropy corresponding to the position, and this anisotropy becomes uneven brightness. Appear. This uneven brightness causes deterioration of the image quality of the stereoscopic video.
Note that the luminance unevenness means that even if an image having the same luminance value of each pixel is input, each pixel is displayed with a different luminance, and the luminance varies.

  It is an object of the present invention to provide a stereoscopic video display device that suppresses uneven luminance.

  In view of the above-described problems, the stereoscopic video display device according to the present invention is a stereoscopic video display device that stereoscopically displays a stereoscopic video by dividing the stereoscopic video into a plurality of pixels, and is divided into a plurality of stereoscopic video images arranged on the same plane. A display panel that displays each of the stereoscopic images, and a magnifying optical system that is arranged corresponding to the display panel and that enlarges each of the divided stereoscopic images displayed on the display panel so that the frame of the corresponding display panel is not displayed. And a diffuser plate that combines the divided stereoscopic video from the magnifying optical system to increase the number of pixels of the stereoscopic video.

  According to such a configuration, the stereoscopic video display device displays each of the divided stereoscopic videos obtained by dividing the stereoscopic video by the display panel. Then, the stereoscopic image display device enlarges each of the divided stereoscopic images displayed on the display panel so that the frame of the display panel corresponding to the set of the magnifying lens array is not displayed in the magnifying optical system.

  In addition, the stereoscopic video display device multiplies the stereoscopic video by combining the split stereoscopic video from the magnifying optical system on the diffusion plate. Then, the stereoscopic video display device stereoscopically displays the stereoscopic video having a large number of pixels on the diffusion plate by the display lens array.

  Here, uneven brightness occurs because light is spread by the magnifying optical system and diffuses with anisotropy corresponding to the position on the diffusion plate. For this reason, luminance unevenness can be suppressed by increasing the working distance from the magnifying optical system to the diffusion plate and reducing the spread of light in the magnifying optical system. Therefore, the stereoscopic image display device has a spread angle that is not more than a preset angle (for example, 6.75 °) so that luminance unevenness can be suppressed in the magnifying optical system, and is set in advance so as to suppress luminance unevenness. Has a working distance greater than or equal to a given distance (eg 99 mm).

  In addition, since the stereoscopic image display device has a diffusion angle that is greater than or equal to a preset angle (for example, 100 °) so that luminance unevenness can be suppressed in the diffusion plate, the diffusion of anisotropic light is smoothed to some extent. And uneven brightness can be suppressed.

According to the present invention, the following excellent effects can be obtained.
According to the present invention, it is possible to suppress luminance unevenness that occurs when a plurality of magnifying optical systems are used, and to suppress deterioration in image quality of a stereoscopic image.

It is the schematic showing the structure of the three-dimensional image display apparatus which concerns on 1st Embodiment of this invention. It is the schematic showing the structure of the expansion optical system of FIG. It is explanatory drawing explaining the directivity of the backlight of FIG. (A)-(d) is explanatory drawing explaining expansion of a three-dimensional image. It is explanatory drawing explaining generation | occurrence | production of brightness irregularity. It is explanatory drawing explaining a working distance and a divergence angle. It is explanatory drawing explaining suppression of a brightness nonuniformity. In the three-dimensional image display apparatus which concerns on 2nd Embodiment of this invention, it is the schematic showing the structure in a correction | amendment step. In the three-dimensional image display apparatus concerning 2nd Embodiment of this invention, it is the schematic showing the structure in a display step. It is a block diagram which shows the structure of the distortion correction apparatus of FIG. (A) And (b) is explanatory drawing explaining correction | amendment of a lens distortion. (A) is a flowchart showing the operation in the correction stage, and (b) is a flowchart showing the operation in the display stage. (A) is an image of a comparative example when observed from the right direction, (b) is a luminance graph of (a), (c) is an image of an example when observed from the right direction, ( d) is a luminance graph of (c). (A) is an image of a comparative example when observed from the front direction, (b) is a luminance graph of (a), (c) is an image of the example when observed from the front direction, ( d) is a luminance graph of (c). (A) is an image of a comparative example when observed from the left direction, (b) is a luminance graph of (a), (c) is an image of an example when observed from the left direction, ( d) is a luminance graph of (c). (A) And (b) is explanatory drawing explaining the conventional integral three-dimensional television.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In each embodiment, means having the same function are denoted by the same reference numerals and description thereof is omitted.

(First embodiment)
[Configuration of stereoscopic display device]
With reference to FIG. 1, the structure of the three-dimensional image display apparatus 1 which concerns on 1st Embodiment of this invention is demonstrated.
As shown in FIG. 1, a stereoscopic video display device 1 displays a stereoscopic video with multiple pixels using an integral photography system, and includes a backlight 10, a display panel 20, an enlargement optical system 30, and a diffusion plate. 40 and a display lens array 50.

A plurality of backlights 10 are arranged on the same plane and irradiate the display panel 20 with light with high directivity. For example, four backlights 10 are arranged in the vertical and horizontal directions. Examples of the backlight 10 include an LED (Light Emitting Diode) light source having a Fresnel lens disposed on the front surface (for example, Phiphotonics Corporation, product name “Hololite”).
The directivity of the backlight 10 will be described later in detail. Moreover, the backlight 10 can be arrange | positioned in arbitrary distances from the display panel 20 mentioned later.

  A plurality of display panels 20 are arranged on the same plane so as to correspond to the backlight 10, and are non-light-emitting display elements that display each of the divided stereoscopic images obtained by dividing the stereoscopic images by the light from the backlight 10. is there. For example, four display panels 20 are arranged so as to face the backlight 10 and to be aligned vertically and horizontally. Further, the display panel 20 is disposed at a position where the light of the display panel 20 can be condensed between the magnifying lens arrays 32A and 32B described later.

  The display panel 20 includes a display screen 22 that displays the divided stereoscopic video and a bezel portion (frame) 24 that does not display the divided stereoscopic video because of its structure. An example of the display panel 20 is a super high vision (7680 × 4320 pixel) transmissive liquid crystal display.

Here, the divided stereoscopic video displayed on the display panel 20 will be briefly described.
For example, a subject is photographed with a general IP stereoscopic camera, and the stereoscopic video (element image group) is divided into the same number (four) as the display panel 20. A divided stereoscopic video (divided element image group) can be generated by enlarging the divided stereoscopic video according to the size of the display panel. Each display panel 20 displays a divided stereoscopic video corresponding to each position.

  A plurality of magnifying optical systems 30 are arranged on the same plane so as to correspond to the display panel 20, and each of the divided stereoscopic images displayed on the display panel 20 is displayed so that the bezel portion 24 of the corresponding display panel 20 is not displayed. It is something that expands. For example, the four magnifying optical systems 30 are arranged to face the display panel 20 so as to be aligned vertically and horizontally.

The magnifying optical system 30 includes a pair of magnifying lens arrays 32A and 32B and a concave lens 36 as shown in FIG.
The magnifying lens arrays 32A and 32B are composed of element lenses 34 arranged two-dimensionally. Two magnifying lens arrays 32A and 32B are arranged so as to face each other. Further, in the magnifying lens arrays 32A and 32B, in order to suppress luminance unevenness, a divergence angle described later is set to be equal to or larger than a preset angle.
One concave lens 36 is arranged so as to face the magnifying lens array 32B, and expands the light emitted from the magnifying lens array 32B.
Here, the magnifying lens array 32A is located on the display panel 20 side, the concave lens 36 is located on the diffusing plate 40 side, and the magnifying lens array 32B is located between the magnifying lens array 32A and the concave lens 36. .

With such a configuration, the magnifying optical system 30 functions as an erecting magnifying optical system that magnifies the erecting equal-magnification image β of the subject.
In addition, as the magnifying optical system 30, an erecting variable magnification array lens device described in "JP 2000-284217 A" can also be used.

Returning to FIG. 1, the description of the configuration of the stereoscopic video display device 1 will be continued.
The diffuser plate 40 joins the divided stereoscopic video from the magnifying optical system 30 to increase the number of pixels of the stereoscopic video. One diffusing plate 40 is disposed at the imaging position of the magnifying optical system 30 (concave lens 36) so that the working distance described later is equal to or greater than a preset distance. Further, the diffusion plate 40 sets a diffusion angle described later to be equal to or larger than a preset angle. For example, examples of the diffusing plate 40 include a holographic diffuser that diffuses light emitted from the magnifying optical system 30.
Note that the increase in the number of pixels refers to increasing the number of pixels of a stereoscopic video captured by an IP stereoscopic camera.

  The display lens array 50 is configured by two-dimensionally arranged element lenses 52, and three-dimensionally displays a three-dimensional image having a plurality of pixels by the diffusion plate 40. For example, one display lens array 50 is arranged so that the diffusion plate 40 is positioned at the focal length of the display lens array 50.

<Direction of backlight>
The directivity of the backlight 10 will be described with reference to FIG.
The backlight 10 needs to have high directivity in order to reduce the crosstalk of the magnifying optical system 30. As shown in FIG. 3, the directivity of the backlight 10 may be equal to or smaller than the angle θ formed by the straight line L1 and the optical axis L2 of the magnifying element lens 32A. This straight line L1 is formed by connecting the lens center C on the incident surface side and the lens outer edge O on the output surface side in the magnifying element lens 32A. For example, the directivity of the backlight 10 is 10 ° or less. In this way, the backlight 10 can suppress stray light to the adjacent element lenses 34 in the magnifying lens arrays 32A and 32B and reduce crosstalk.

<Enlargement of stereoscopic images>
With reference to FIG. 4, the expansion of the stereoscopic video in the stereoscopic video display device 1 will be described.
As shown in FIG. 4A, the magnifying lens arrays 32A and 32B have a subject on the opposite side of the subject 90 around the position where the light of the display panel 20 is condensed between the magnifying lens arrays 32A and 32B. 90 erecting equal-magnification images 92 are formed. Therefore, as shown in FIG. 4B, a concave lens 36 is arranged on the side of the magnifying lens array 32B. Then, the concave lens 36 can enlarge the subject 90 and form an upright enlarged image 94 of the subject 90.

  Therefore, as shown in FIGS. 4C and 4D, the magnifying optical system 30 enlarges the divided stereoscopic image emitted from the display screen 22 of the display panel 20 so that the bezel portion 24 of the display panel 20 is not displayed. Then, an image is formed at the position of the diffusion plate 40. At this time, in the diffusing plate 40, the boundary between the divided stereoscopic image enlarged by a certain magnifying optical system 30 and the divided stereoscopic image enlarged by another adjacent magnifying optical system 30 coincide. In this manner, the stereoscopic image display apparatus 1 can combine the divided stereoscopic images from the magnifying optical system 30 without any gaps, thereby increasing the number of pixels of the stereoscopic image.

<Suppression of uneven brightness>
With reference to FIGS. 5 to 7, suppression of luminance unevenness in the stereoscopic video display device 1 will be described.
FIG. 5 illustrates the stereoscopic video display device 1 in which uneven brightness occurs. Further, in FIG. 5, the light shown the light passing through the one first display panel ₂₀₁ and the enlarging optical system 30 ₁ by solid arrows, passes through the two eyes of the display panel 20 ₂ and the magnifying optical system 30 ₂ Illustrated with dashed arrows.

As shown in FIG. 5, the light passing through the upper side of the magnifying optical systems 30 ₁ and 30 ₂ is diffused by the diffusion plate 40 while being biased toward the upper side of the drawing. On the other hand, the light passing through the lower side of the magnifying optical systems 30 ₁ and 30 ₂ is diffused by the diffusion plate 40 while being biased toward the lower side of the drawing. Thus, the light diffused by the diffusion plate 40 has anisotropy depending on the position, and appears as luminance unevenness. Therefore, the stereoscopic image display device 1 suppresses this luminance unevenness by combining two kinds of methods.

First, the first method will be described.
As shown in FIG. 6, uneven brightness can be suppressed by increasing the working distance WD and decreasing the light spread angle θ. In the present embodiment, the spread angle θ is set to 6.75 ° or less. Furthermore, the working distance WD was set to 99 mm or more by setting the F value of the magnifying lens arrays 32A and 32B to 6.4 or more.

The working distance WD is a distance from the magnifying optical system 30 to the diffusion plate 40. More specifically, the working distance WD is a distance from the lens surface on the concave lens 36 side in the magnifying lens array 32B to the flat surface on the concave lens 36 side in the diffusion plate 40.
Further, the spread angle θ is an angle at which the light of the divided stereoscopic video spreads. More specifically, the spread angle θ is an angle between the optical axis of the magnifying optical system 30 and the light beam magnified by the magnifying optical system 30.

Next, the second type of method will be described.
The light magnified by the magnification optical systems 30 ₁ and 30 ₂ is diffused by the diffusion plate 40 around the magnified direction. Therefore, by increasing the diffusion angle φ of the diffusing plate 40, the diffusion of light having anisotropy can be smoothed to some extent and luminance unevenness can be suppressed. In the present embodiment, a holographic diffuser having a diffusion angle φ of 100 ° or more is used as the diffusion plate 40.

  As shown in FIG. 6, the diffusion angle φ is an angle at which light is diffused by the diffusion plate 40. More specifically, the diffusion angle φ is a full-width display of the half value of the central illuminance at the diffusion plate 40 (FWHM).

As a result of combining the two kinds of methods, as shown in FIG. 7, the light passing through the upper side of the magnifying optical systems 30 ₁ and 30 ₂ is diffused by the diffusion plate 40 to the lower side of the drawing. Further, the light passing through the lower side of the magnifying optical systems 30 ₁ and 30 ₂ is diffused by the diffusion plate 40 to the upper side of the drawing. In this way, the stereoscopic video display device 1 can suppress luminance unevenness.

[Action / Effect]
As described above, the stereoscopic video display device 1 can increase the quality of the IP stereoscopic video because the stereoscopic video can be multi-pixeled and luminance unevenness can be suppressed.
Furthermore, since the number of display panels 20 is not limited, the stereoscopic image display device 1 can be increased in number of pixels without an upper limit.
Furthermore, the stereoscopic image display apparatus 1 uses the backlight 10 with high directivity to reduce crosstalk in the magnifying optical system 30, so that resolution degradation due to crosstalk does not occur, and the degradation of stereoscopic image quality is suppressed. can do.

(Second Embodiment)
With reference to FIG. 8, differences from the first embodiment will be described regarding the configuration of the stereoscopic video display apparatus 1 </ b> B according to the second embodiment of the present invention.
The stereoscopic image display apparatus 1B is different from the first embodiment in that lens distortion caused by the magnifying optical system 30 is corrected.

A procedure for correcting lens distortion in the stereoscopic image display apparatus 1B will be briefly described.
As shown in FIG. 8, the reference sheet 42 is attached to the diffusion plate 40B. Further, the display lens array 50 is detached from the stereoscopic image display device 1B (illustrated by a one-dot chain line). Then, the distortion correction device (distortion correction means) 60 performs projective transformation and affine transformation on a reference image described later, and outputs the result to the display panel 20B. At this time, an observer (not shown) visually determines whether or not lens distortion has been corrected, and inputs the determination result to the distortion correction device 60.
The stage in which the stereoscopic image display apparatus 1B corrects lens distortion is referred to as a “correction stage”.

After correcting the lens distortion, as shown in FIG. 9, the reference sheet 42 is removed from the diffusion plate 40B (shown by a one-dot chain line), and the display lens array 50 is disposed. Then, the distortion correction device 60 performs projective transformation and affine transformation on the input stereoscopic video and outputs the result to the display panel 20B.
In this way, the stereoscopic video display device 1B can display a stereoscopic video with lens distortion corrected.
The stage in which the stereoscopic video display device 1B displays a stereoscopic video after correcting the lens distortion is referred to as a “display stage”.

[Configuration of stereoscopic display device]
The configuration of the stereoscopic video display device 1B will be described with respect to differences from the first embodiment (see FIGS. 8 and 9 as appropriate).
In the correction stage, the display panel 20B receives the reference image from the distortion correction device 60 and displays the input reference image. Here, all the display panels 20B display the same reference image. This reference image is an image in which a predetermined pattern, for example, the same right triangle is drawn in a mesh shape. In addition, the reference image may have a dot pattern in which the center of each element lens 52 is represented by a point.
At the display stage, the display panel 20B is the same as in the first embodiment.

In the diffusing plate 40B, the reference sheet 42 is attached to the emission surface side (the display lens array 50 side) at the correction stage. The reference sheet 42 is a sheet on which the same pattern as the reference image is drawn. Here, the number of right triangles or points drawn on the reference sheet 42 is equal to the total number of right triangles or points of the reference images displayed on all the display panels 20B.
In the display stage, the diffusion plate 40B is the same as that in the first embodiment.

In the correction stage, the distortion correction device 60 generates a reference image based on preset image setting parameters, and outputs the generated reference image to the display panel 20B. In addition, the distortion correction device 60 performs projective transformation and affine transformation so that the stereoscopic image of the reference image matches the reference sheet 42.
It is assumed that the observer visually determines whether or not the three-dimensional image of the reference image matches the reference sheet 42 and inputs the determination result to the distortion correction device 60.

  Further, the distortion correction device 60 performs projection transformation and affine transformation on the stereoscopic image using the projection transformation matrix and the affine transformation matrix when the stereoscopic image of the reference image is matched with the reference sheet 42 in the display stage, and the lens Correct distortion.

[Configuration of distortion correction device]
With reference to FIG. 10, the structure of the distortion correction apparatus 60 is demonstrated.
As illustrated in FIG. 10, the distortion correction apparatus 60 includes a reference image generation unit 62, a projective conversion unit 64, an affine conversion unit 66, and a control unit 68.

  The reference image generation means 62 is configured to receive an image setting parameter from outside and generate a reference image based on the input image setting parameter. This image setting parameter is a parameter necessary for generating a reference image, for example, the number and size of triangular meshes.

  The projective transformation means 64 receives the reference image from the reference image generation means 62 and performs projective transformation on the reference image so that the control points of the inputted reference image coincide with the reference sheet 42.

Specifically, as shown in FIG. 11A, the projective transformation means 64 uses the four corners of the reference image as control points Pt, and the control points Pt of the reference image coincide with the four corners of the reference sheet 42. Projective transformation.
In FIG. 11, the triangular mesh of the reference image is illustrated by a broken line, and the triangular mesh of the reference sheet 42 is illustrated by a solid line. Further, in FIG. 11A, only the lower right portion of the reference image and the reference sheet 42 is illustrated.

  The affine transformation unit 66 receives the reference image from the projection transformation unit 64 and affine transforms the reference image so that the input reference image and the triangular mesh of the reference sheet 42 coincide.

Specifically, as shown in FIG. 11B, the affine transformation means 66 performs affine transformation individually on all the triangular meshes with the vertex of each triangular mesh of the reference image as the control point Pt.
In FIG. 11B, only a part of the control point Pt, the reference image, and the triangular mesh of the reference sheet 42 are illustrated.

  The control means 68 inputs a determination result from the observer and instructs the projection conversion means 64 and the affine conversion means 66 based on the input determination result. The command by the control means 68 will be described in the operation of the distortion correction device 60.

Here, the control unit 68 inputs a determination result by an observer operating a mouse and a keyboard (not shown).
When the stereoscopic image of the reference image matches the reference sheet 42, the observer inputs “match” to the control means 68.
In addition, when the stereoscopic image of the reference image does not match the reference sheet 42, the observer inputs “mismatch” to the control unit 68.

[Operation of distortion corrector]
<Correction stage>
With reference to FIG. 12, the operations of the correction stage and the display stage in the distortion correction apparatus 60 will be described in order (see FIG. 10 as appropriate).
As shown in FIG. 12A, the reference image generation unit 62 generates a reference image based on the image setting parameter (step S1).
The projective transformation means 64 performs projective transformation with the four corners of the reference image generated in step S1 as control points Pt so that the control points Pt of the reference image coincide with the four corners of the reference sheet 42 (step S2).

The affine transformation means 66 performs affine transformation so that all the triangular meshes coincide with the triangular meshes of the reference sheet 42 using the vertices of the triangular meshes of the reference image projectively transformed in step S2 as control points Pt (step S3). .
The affine transformation means 66 outputs the reference image affine transformed in step S3 to the display panel 20B (step S4).

The observer visually determines whether or not the reference image output to the display panel 20B matches the reference sheet 42. Then, the observer inputs the determination result to the control means 68.
The control means 68 determines whether the determination result input from the observer is “match” or “mismatch” (step S5).

When the determination result is “match” (Yes in step S5), the control unit 68 instructs the projection conversion unit 64 and the affine conversion unit 66 to execute step S6.
The projective transformation means 64 stores the projective transformation matrix when the projective transformation is performed in step S2 in a memory not shown.
The affine transformation means 66 stores the affine transformation matrix when the affine transformation is performed in step S3 in a memory (not shown) (step S6), and ends the correction stage processing.

When the determination result is “mismatch” (No in step S5), the control unit 68 instructs the projection conversion unit 64 and the affine conversion unit 66 to execute step S7.
The projective transformation means 64 changes the projective transformation matrix when the projective transformation is performed in step S2 by a preset value.
The affine transformation means 66 changes the affine transformation matrix when the affine transformation is performed in step S3 by a preset value (step S7), and returns to the processing in step S2.
That is, until the determination result is “match”, the projective transformation unit 64 and the affine transformation unit 66 repeatedly perform the projective transformation and the affine transformation on the reference image while changing the projection transformation matrix and the affine transformation matrix stored in the memory. Apply.

<Display stage>
As shown in FIG. 12B, the projection conversion means 64 receives a stereoscopic video from the outside (step S10).
The projective transformation means 64 performs projective transformation on the stereoscopic video input in step S10 using the projective transformation matrix stored in step S6 (step S11).

The affine transformation means 66 performs affine transformation on the stereoscopic video obtained by projective transformation in step S11 using the affine transformation matrix stored in step S6 (step S12).
The affine transformation means 66 outputs the 3D image affine transformed in step S12 to the display panel 20B (step S13).
In this way, the distortion correction device 60 can display a stereoscopic image in which lens distortion is corrected.

Since the lens distortion correction method is described in Reference Document 1 below, further explanation is omitted.
Reference 1: Oka City, Hiura, Miura, Senrai: “Integral 3D image display by multiple projectors using distortion correction method,” Eiji University of Science, 11-5 (2013)

[Action / Effect]
As described above, the stereoscopic video display apparatus 1B can correct lens distortion by combining projective transformation and affine transformation in addition to the same effects as those of the first embodiment. Accordingly, the stereoscopic video display device 1B can accurately correct the enlarged image and accurately combine the plurality of enlarged images.

As mentioned above, although each embodiment of this invention was explained in full detail, this invention is not limited to above-described embodiment, The design change etc. of the range which does not deviate from the summary of this invention are also included.
In each of the above-described embodiments, the stereoscopic video display device has been described as displaying IP stereoscopic video. However, the present invention is not limited to this. For example, the stereoscopic video display device may display a binocular stereoscopic video.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 13 to 15.
Similar to the first embodiment, the stereoscopic image display device 1 is configured to include four backlights 10, the display panel 20, the magnifying optical system 30, one diffusion plate 40, and a display lens array 50. Two types of stereoscopic image display devices 1 having different working distances and diffusion angles in this configuration were prepared. Hereinafter, a stereoscopic video display device 1 in which uneven luminance is suppressed will be described as an example, and the stereoscopic video display device 1 in which uneven luminance has occurred will be described as a comparative example.

  In the example, the divergence angle θ of the magnifying optical system 30 was 6.75 °, and the working distance WD was 99.0 mm. In the example, the width of the display screen 22 was 106.56 mm, and the magnification ratio of the magnification optical system 30 was 1.22 times. In the example, the diffusion angle of the diffusion plate 40 was 100 °.

  In the comparative example, the expansion angle θ of the magnifying optical system 30 was 29.4 °, and the working distance WD was 20.8 mm. In the comparative example, the width of the display screen 22 and the magnification ratio of the magnification optical system 30 were the same as those in the example. In the comparative example, the diffusion angle of the diffusion plate 40 was 60 °.

Then, the entire white divided stereoscopic video was input to the stereoscopic video display devices 1 of the example and the comparative example, and the stereoscopic video was displayed. In this state, the brightness unevenness was visually recognized, and the brightness unevenness index value was calculated. This luminance unevenness index value is expressed by the following formula (1) using a maximum luminance max and a minimum luminance min of a luminance graph described later. That is, as the luminance unevenness index value increases, the luminance unevenness increases.
Brightness unevenness index value = (max−min) / (max + min) (1)

  As shown in FIG. 13A, when viewed from the right direction, in the comparative example, the left side of the screen is not visible, and the combined portion of the divided stereoscopic images located in the center of the screen is dark. Moreover, the luminance graph in the horizontal line of Fig.13 (a) was illustrated in FIG.13 (b). In the luminance graph, the vertical axis represents the luminance value of 256 gradations, and the horizontal axis represents the position on the horizontal line. From FIG. 13B as well, in the comparative example, it was found that the luminance decreased at the joint portion between the left side of the screen and the center of the screen. In the comparative example, the luminance unevenness index value was 0.94.

  When observed from the right direction as shown in FIG. 13C, in the example, the left side of the screen is somewhat dark, but it is not dark at the joint portion at the center of the screen. Moreover, the luminance graph in the horizontal line of FIG.13 (c) was illustrated in FIG.13 (d). Also from FIG. 13D, it was found that in the example, the luminance unevenness was small over the entire screen. In the example, the luminance unevenness index value is 0.44.

  As shown in FIG. 14A, when observed from the front direction, in the comparative example, both ends of the screen became invisible and the joint portion at the center of the screen became dark. Moreover, the luminance graph in the horizontal line of Fig.14 (a) was illustrated in FIG.14 (b). Also from FIG. 14B, it was found that in the comparative example, the luminance was reduced at the joint between the both ends of the screen and the center of the screen. In the comparative example, the luminance unevenness index value was 0.81.

  As shown in FIG. 14C, when observed from the front direction, both ends of the screen are slightly darkened in the embodiment, but are not darkened at the joint portion at the center of the screen. Moreover, the luminance graph in the horizontal line of FIG.14 (c) was illustrated in FIG.14 (d). Also from FIG. 14D, it was found that there was little luminance unevenness in the entire screen in the example. In the example, the luminance unevenness index value is 0.46.

  When observed from the left direction as shown in FIG. 15A, in the comparative example, the right side of the screen became invisible and the joint portion at the center of the screen became dark. Further, FIG. 15B shows a luminance graph on the horizontal line in FIG. Also from FIG. 15B, it was found that in the comparative example, the luminance was reduced at the joint portion between the right side of the screen and the center of the screen. In the comparative example, the luminance unevenness index value was 0.94.

As shown in FIG. 15C, when observed from the left direction, in the example, the entire screen was somewhat darkened. Moreover, the luminance graph in the horizontal line of FIG.15 (c) was illustrated in FIG.15 (d). Also from FIG. 15D, it was found that in the example, the luminance unevenness was small over the entire screen. In the example, the luminance unevenness index value is 0.55.
As described above, it was found that the brightness unevenness can be suppressed in the example because the brightness unevenness index value is about half that of the comparative example.

1,1B stereoscopic image display device 10 backlight 20, 20B display panel 30 magnifying optical system 40, 40B diffuser plate 42 reference sheet 50 display lens array 60 distortion correction device (distortion correction means)
62 Reference image output means 64 Projective transformation means 66 Affine transformation means 68 Control means

Claims (3)

A stereoscopic image display device for stereoscopically displaying a stereoscopic image by increasing the number of pixels,
A plurality of display panels arranged on the same plane and displaying each of the divided stereoscopic images obtained by dividing the stereoscopic images;
An enlarged optical system that is arranged corresponding to the display panel and that enlarges each of the divided stereoscopic images displayed on the display panel so that the corresponding frame of the display panel is not displayed;
A diffusion plate for combining the three-dimensional video from the magnifying optical system to increase the number of pixels of the three-dimensional video,
In the magnifying optical system, a spread angle that represents an angle at which the light of the divided stereoscopic image spreads is equal to or smaller than a preset angle so that luminance unevenness can be suppressed,
The diffusion plate has a diffusion angle representing an angle at which the light of the stereoscopic image is diffused is an angle set in advance so as to suppress the luminance unevenness,
A stereoscopic image display device, wherein a working distance from the magnifying optical system to the diffusion plate is equal to or greater than a preset distance so as to suppress the luminance unevenness. A backlight that is arranged corresponding to the display panel and irradiates the display panel with light;
A display lens array in which element lenses are two-dimensionally arranged and three-dimensionally display a three-dimensional image with a plurality of pixels on the diffusion plate;
The display panel displays the divided stereoscopic video of the integral photography system,
The magnifying optical system has a set of magnifying lens arrays arranged corresponding to the display panel and in which element lenses are two-dimensionally arranged,
The backlight has a directivity of the light to be irradiated, a straight line connecting the lens center on the incident surface side and the outer edge of the lens on the output surface side in the element lens of the magnifying lens array located on the display panel side, and The stereoscopic image display device according to claim 1, wherein the stereoscopic image display device has an angle less than or equal to an optical axis of the magnification element lens. The magnifying optical system has the divergence angle of 6.75 ° or less,
The diffusion plate has a diffusion angle of 100 ° or more,
The stereoscopic image display apparatus according to claim 1, wherein the working distance is 99 mm or more.