JP2010271505A - Stereoscopic display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stereoscopic display device that obtains a wide observation area without using a wide-angle projection lens. <P>SOLUTION: Among projectors 61 to 65, the projectors 61 and 65 are disposed so that their respective optical axes K are parallel to the direction (X direction in FIG. 2) of an optical axis orthogonal to the light-incident surface 10a of a vertical diffusion screen 10 and outside the vertical diffusion screen 10 in a horizontal direction (Y direction in FIG. 2). That is, a light beam from each of the projectors 61 and 65 satisfies θ>tan<SP>-1</SP>(W/D). Accordingly, the incident angle θ at which emission light L1 from the projector 61 enters the vertical diffusion screen 10 can be made larger than tan<SP>-1</SP>(W/D), and the emission angle ϕ of the vertical diffusion light L2 relative to the optical axis K can be made larger. This causes expansion of a partial observation area R1 of the stereoscopic display device 1 without using a wide-angle projection lens. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a stereoscopic display device that enables stereoscopic display without wearing special glasses.

  As an apparatus for displaying a stereoscopic image, there is an apparatus that generates parallax with respect to left and right eyes by using polarized glasses or the like. In recent years, a technique that enables stereoscopic display without using such polarized glasses is known.

  For example, Patent Document 1 discloses a stereoscopic display device using a plurality of projectors. This stereoscopic display device reproduces light emitted from the surface of a stereoscopic image by a plurality of projectors. Such a stereoscopic display device includes, for example, a plurality of projectors and a screen arranged in the horizontal direction. The screen diffuses light projected from the projector to reproduce a stereoscopic image. Specifically, the screen has a Fresnel lens and a diffusion layer, and this diffusion layer has a large diffusion effect in the vertical direction and does not have a large diffusion effect in the horizontal direction.

  Such a stereoscopic display device reproduces a stereoscopic image by a plurality of light beams emitted from the plurality of projectors, for example. For this reason, stereoscopic vision is possible without using special glasses, and there is a feature that it is suitable for natural video expression.

  Patent Document 2 discloses a technique for enlarging an area that can be observed by an observer by reflecting light that has been emitted from a projector but does not reach the screen, and is reflected by a mirror. Yes.

JP 2008-288616 A (paragraph [0067], FIG. 5) JP2007-187754 (FIG. 1)

  However, in the above-described technique, the diffusion layer of the screen does not have a large diffusion effect in the horizontal direction, so that the light emitted from the projector enters the Fresnel lens, is refracted, and enters the diffusion layer. The diffusion layer proceeds in the horizontal direction without much diffusion. As a result, there is a problem in that light does not reach the observer's eyes outside the angle of view of the projection lens, and the partial observation area, which is an area where the observer can observe at least part of the screen, becomes narrow. There is also a problem that the entire observation area becomes smaller as the partial observation area becomes smaller. The entire observation area is an area where light reaches the observer's eyes from the entire screen.

  Even when the technique of Patent Document 2 is used, the partial observation area and the entire observation area cannot be expanded unless a projection lens having a relatively large angle of view is used.

However, in order to obtain a wide-angle projection lens, it may be necessary to increase the number of lenses or use a large lens, resulting in an increase in the size of each projector. In addition, it is necessary to increase the number of projectors and the number of light beams to reproduce high-quality 3D images. It is difficult to reproduce the statue.
In view of the circumstances as described above, an object of the present invention is to provide a stereoscopic display device capable of ensuring a wide observation area without using a wide-angle projection lens.

In order to achieve the above object, a stereoscopic display device according to one embodiment of the present invention includes a plurality of projectors and a screen.
Each of the plurality of projectors includes a spatial light modulation element that spatially modulates incident light and a projection lens that projects light from the spatial modulation element. The screen has a light incident surface on which light projected from the projector is incident, and diffuses the incident light more in the vertical direction than in the horizontal direction.
The plurality of projectors are arranged at equidistant positions in the optical axis direction from the light incident surface of the screen, with the optical axis directions of the projection lenses aligned with the direction orthogonal to the light incident surface. The horizontal width of the screen is W, the projection depth, which is the distance between the projector and the screen in the optical axis direction, is D, and the incident angle of light rays from the projector on the horizontal plane is θ. Then, light rays from at least one of the projectors satisfy θ> tan ⁻¹ (W / D).

In the present invention, since the projector is arranged so that the light beam from at least one projector satisfies θ> tan ⁻¹ (W / D), the incident angle of the light beam from at least one projector to the screen. Θ> tan ⁻¹ (W / D), and the observation region can be enlarged without using a wide-angle projection lens.

  The at least one projector may be provided such that the optical axis of the projection lens of the projector is positioned on the outside in the horizontal direction of the screen. Thereby, the incident angle of the light beam from the at least one projector to the screen can be increased, and the observation area of the light diffused by the screen can be enlarged.

The projectors arranged at both ends in the horizontal direction may be provided so that the optical axes of the projection lenses of the respective projectors are located outside the horizontal direction of the screen.
As a result, it is possible to enlarge a part of the observation area with good balance in the horizontal direction.

The screen may include a Fresnel lens provided on the light incident surface side in the optical axis direction.
Thereby, the light beam from the projector can be refracted by the Fresnel lens, and the refracted light beam can be diffused in the vertical direction. In other words, the (entire) observation area can be changed by the Fresnel lens.

In the spatial light modulation element of the projector that projects a light beam satisfying θ> tan ⁻¹ (W / D), the center of the display area of the spatial light modulation element is horizontal with respect to the optical axis of the projection lens of the projector. It may be arranged so as to be eccentric.
Thereby, the light modulated by the spatial light modulator can be incident obliquely on the projection lens, and as a result, the observation area can be enlarged.

  Thus, according to the present invention, a wide observation area can be secured without using a wide-angle projection lens.

1 is a perspective view of a stereoscopic image display device according to an embodiment of the present invention. It is a top view of the three-dimensional image display apparatus shown in FIG. FIG. 3 is a side view of the stereoscopic image display device shown in FIG. 2. It is a figure which shows the spreading | diffusion characteristic of the horizontal direction of a vertical diffusion screen of a stereo image display apparatus, and a perpendicular direction. It is a schematic diagram explaining the principle of the stereoscopic vision of a stereoscopic image display apparatus. It is a top view which shows the partial observation area | region using the three-dimensional image display apparatus shown in FIG. It is a top view which shows the whole surface observation area | region using the three-dimensional image display apparatus shown in FIG. It is a top view which shows the structure and partial observation area | region of the three-dimensional image display apparatus of 2nd Embodiment concerning this invention. It is a top view which shows the structure of the stereo image display apparatus shown in FIG. 8, and a whole surface observation area | region. It is a top view which shows the structure of the three-dimensional image display apparatus of 3rd Embodiment concerning this invention. It is a top view which shows the partial observation area | region of the conventional stereo image display apparatus. It is a top view which shows the whole surface observation area | region of the conventional stereo image display apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
[Configuration of stereoscopic image display apparatus]

  1 is a perspective view of a stereoscopic image display apparatus according to an embodiment of the present invention, FIG. 2 is a plan view of the stereoscopic image display apparatus shown in FIG. 1, and FIG. 3 is a side view of the stereoscopic image display apparatus shown in FIG. .

  The stereoscopic image display apparatus 1 is an apparatus that displays a stereoscopic image using a light beam reproduction method. The stereoscopic image display apparatus 1 includes a base 2, a substrate holding unit 3 provided on the base 2, a projector base 4, a screen frame 5, projectors 61 to 65, a substrate 7, a side surface unit 8, and a vertical unit. It comprises a diffusion screen 10 and a cooling fan (not shown).

  A plurality of projectors 61 to 65 are arranged on the projector base 4 in the horizontal direction (Y direction in FIGS. 1 and 2). The substrate 7 is held by the substrate holding unit 3 and a circuit for driving and controlling the projectors 61 to 65 is mounted. The side surface portion 8 prevents the light projected from the projectors 61 to 65 from leaking to the outside of the stereoscopic image display device 1 and reflects the projected light. The vertical diffusion screen 10 is held by the screen frame 5 and diffuses a plurality of image lights projected from the projectors 61 to 65 in the vertical direction (Z direction), respectively, so that a continuous viewpoint in the horizontal direction (Y direction) can be obtained. An image is projected.

  In the light beam reproduction method, a plurality of cameras are used when an image is captured, an imaging range in charge for each camera is set, and images with parallax captured by each camera are prepared. Then, according to the conversion matrix for each pixel calculated from the imaging position, the captured image is converted to obtain a projection image. By combining the projection images thus obtained, one stereoscopic image is generated. In the present embodiment, projection images obtained by conversion from individual images captured by the plurality of cameras are projected from the projectors 61 to 65 toward the vertical diffusion screen 10, and each of the vertical diffusion screens 10 has a vertical direction. The image is projected as a series of long vertical lines.

[Projectors 61-65]
As shown in FIGS. 2 and 3, the projectors 61 to 65 project images (videos) on the vertical diffusion screen 10. The projectors 61 to 65 are respectively arranged in the horizontal direction (Y direction in FIGS. 1 and 2) so that the emission surfaces of the projection light are substantially aligned with one plane (YZ plane). Further, the distance in the optical axis direction (K direction) of the projection lens with respect to the vertical diffusion screen 10 of each projector 61 to 65 is the same. Here, the optical axis direction (K direction) of the projection lens is the same as the X direction, and is a direction orthogonal to the light incident surface 10 a of the vertical diffusion screen 10. The projectors 61 to 65 are arranged at the same height in the vertical direction (Z direction) as shown in FIGS. 1 and 2.

  The projectors 61 and 65 at both ends of the projectors 61 to 65 are arranged such that their optical axes K are positioned outside the vertical diffusion screen 10 in the horizontal direction (Y direction shown in FIG. 2).

That is, the positions of the projector 61 and the projector 65 at both ends are determined so as to satisfy θ> tan ⁻¹ (W / D). Here, W is the width of the vertical diffusion screen 10 in the horizontal direction (Y direction shown in FIG. 2). D is a projection depth which is an interval in the optical axis direction (X direction) between the projectors 61 to 65 and the vertical diffusion screen 10. More specifically, D is the distance in the optical axis direction (X direction) between the vertical diffusion screen 10 and the center of the projection lens in the projector. θ is an incident angle on the horizontal plane (XY plane) of light rays from the individual projectors 61 and 65 to the vertical diffusion screen 10.

  Among the projectors 61 to 65, the position in the horizontal direction of the optical axis K of the projection lens of the projector 63 at the center in the horizontal direction and the center of the vertical diffusion screen 10 are substantially the same. On the other hand, the positions in the horizontal direction of the optical axis K of the projection lenses of the other projectors 61, 62, 64, 65 and the center of the vertical diffusion screen 10 do not match. Accordingly, the positions of the projected images in the horizontal direction are set so that the images projected from the projectors 61, 62, 64, 65 other than the center coincide with each other on the light incident surface 10a of the vertical diffusion screen 10. It has been shifted. An example of this projection image shift will be described later.

  The projectors 61 to 65 each incorporate a light source, a spatial light modulation element, a projection lens, and an illumination optical system, and the projectors 61 to 65 each function as an independent projection device. However, when the spatial light modulation element is an EL (electroluminescence) element that emits light by itself, the light source and the illumination optical system may not be provided. The light source is, for example, a white light source module that emits white light, and specifically, a white light emitter composed of a blue LED and a yellow phosphor is used. The spatial light modulation element modulates light for each of blue, green, and red incident from a light source to generate image light. The supply of image data to the spatial light modulator is controlled by a circuit mounted on the substrate 7 so that a predetermined image is displayed from each of the projectors 61 to 65. As the spatial light modulation element, for example, a reflective liquid crystal element is used. In addition to the reflective liquid crystal display element, the spatial light modulation element is applied like a transmissive liquid crystal display element or DLP (registered trademark Digital Light Processing) equipped with DMD (Digital Micro-mirror Device). A device that performs light intensity modulation for each pixel in accordance with an image (video) signal can also be used.

[Vertical diffusion screen 10]
The vertical diffusion screen 10 is provided in parallel to the YZ plane on which the projectors 61 to 65 are disposed. In the vertical diffusion screen 10, the horizontal width of the vertical diffusion screen 10 is W. The vertical diffusion screen 10 diffuses incident light from the projectors 61 to 65 at a predetermined diffusion angle in the horizontal direction and the vertical direction, respectively.

FIG. 4 is a diagram showing diffusion characteristics of the vertical diffusion screen 10 in the horizontal direction and the vertical direction.
The vertical diffusion screen 10 diffuses incident light at a predetermined diffusion angle (diffusion amount) different in the horizontal direction and the vertical direction. Here, the diffusion angles in the horizontal direction and the vertical direction are set such that the horizontal diffusion angle is smaller than the vertical diffusion angle. More specifically, incident light from the projectors 61 to 65 does not diffuse so much in the horizontal direction (Y direction) (FIG. 4A), but greatly diffuses in the vertical direction (Z direction) (FIG. 4 ( As in b)), the diffusion angles in the horizontal direction and the vertical direction are determined.

  Here, as shown in FIG. 4A, the light beam 11 incident on the vertical diffusion screen 10 is not so diffused in the horizontal direction (Y direction). For this reason, light rays of projection images from some of all the projectors 61 to 65 reach the observer's eyes through the vertical diffusion screen 10.

  On the other hand, as shown in FIG. 4B, the light beam 11 incident on the vertical diffusion screen 10 is greatly diffused in the vertical direction (Z direction). For this reason, for example, the light beam 11 projected on the light incident surface upper part or the light incident surface lower part of the vertical diffusion screen 10 is diffused greatly in the vertical direction (Z direction) by the vertical diffusion screen 10 and the light beam 13 from the vertical diffusion screen 10. And the diffused light beam 13 enters the observer's eyes.

FIG. 5 is a schematic diagram for explaining the principle of stereoscopic vision of the stereoscopic image display device 1.
The observer 16 observes the light emitted from the projectors 61 to 65 through the vertical diffusion screen 10. Specifically, if the light beam emitted from the surface of the stereoscopic image 15 to be displayed enters the left eye 17 and the right eye 18 of the viewer 16, the viewer 16 stereoscopically views the stereoscopic image 15. be able to. In FIG. 5, the light emitted from the projector 62 travels almost straight on the vertical diffusion screen 10 and enters the left eye 17, and the light emitted from the projector 63 travels substantially straight on the vertical diffusion screen 10 and enters the right eye 18. To do. In this way, the stereoscopic image 15 to be displayed is made to correspond to the light rays of the projectors 61 to 65, thereby enabling stereoscopic display with the naked eye.

[Partial observation area]
FIG. 6 is a plan view showing a partial observation region using the stereoscopic image display device 1 shown in FIG.
Light emitted from the projectors 61 to 65 is diffused in the vertical direction by the vertical diffusion screen 10 and emitted as vertical diffusion light from the vertical diffusion screen 10. Here, the emitted light L1 of the projector 61 arranged at one end in the horizontal direction among the projectors 61 to 65 is incident on the vertical diffusion screen 10 at an incident angle θ (> tan ⁻¹ (W / D)) with respect to the optical axis K. Is incident on. Therefore, the vertical diffusion light L2 is emitted from the vertical diffusion screen 10 at an emission angle (refraction angle) φ. The emission angle φ is larger than the emission angle of light incident on the vertical diffusion screen 10 at an incident angle of tan ⁻¹ (W / D) or less with respect to the optical axis K.

Similarly, the emitted light L3 from the projector 65 is incident on the vertical diffusion screen 10 at an incident angle θ (> tan ⁻¹ (W / D)) with respect to the optical axis K. For this reason, the vertical diffusion light L4 is emitted from the vertical diffusion screen 10 at an emission angle φ. The emission angle φ is larger than the emission angle of light incident on the vertical diffusion screen 10 at an incident angle of tan ⁻¹ (W / D) or less with respect to the optical axis K.
As a result, a partial observation region R1 indicated by hatching in FIG. 6 is generated by the light beams emitted from the projectors 61 to 65.

FIG. 7 is a plan view showing an entire observation area using the stereoscopic image display device 1 shown in FIG.
The outgoing light L5 emitted from the projector 61 is not diffused much in the horizontal direction by the vertical diffusion screen 10, but is diffused in the vertical direction, and emitted from the vertical diffusion screen 10 as vertical diffused light L6. The vertical diffused light L6 travels substantially straight with respect to the vertical diffused light L5 in the horizontal direction.

Similarly, the emitted light L7 emitted from the projector 65 is diffused in the vertical direction without being diffused much in the horizontal direction by the vertical diffusion screen 10, and is emitted from the vertical diffusion screen 10 as the vertical diffused light L8. The vertical diffused light L8 travels substantially straight with respect to the vertical diffused light L7 in the horizontal direction.
As a result, the entire surface observation region R2 indicated by the oblique lines in FIG. 7 is generated by the light beams emitted from the projectors 61 to 65.

[Action etc.]
As described above, according to the present embodiment, the projector 61 and the projector 65 among the projectors 61 to 65 are configured such that the optical axes K are orthogonal to the light incident surface 10a of the vertical diffusion screen 10 (X shown in FIG. 2). In parallel with the horizontal direction (Y direction shown in FIG. 2). That is, the light rays from the projector 61 and the projector 65 satisfy θ> tan ⁻¹ (W / D). Therefore, the incident angle θ at which the outgoing light L1 from the projector 61 enters the vertical diffusion screen 10 is made larger than tan ⁻¹ (W / D), and the outgoing angle φ of the vertical diffused light L2 with respect to the optical axis K is made larger. Can do. As a result, the partial observation region R1 of the stereoscopic image display device 1 can be enlarged without using a wide-angle projection lens.

FIG. 11 is a plan view showing a partial observation region of a conventional stereoscopic image display device.
As shown in FIG. 11, a conventional stereoscopic image display apparatus 300 includes a plurality of projectors 301, 302, and 303 and a vertical diffusion screen 304 that vertically diffuses incident light from these projectors 301 to 303. The projectors 301 and 303 are not provided such that their optical axes are positioned outside the vertical diffusion screen 304 in the horizontal direction.

  The vertical diffusion screen 304 includes a Fresnel lens 305 and a diffusion layer 306. The diffusion layer 306 has a large diffusion effect in the vertical direction and does not have much diffusion effect in the horizontal direction. For this reason, the light beams emitted from the projectors 301 to 303 are incident on the Fresnel lens 305, refracted, and incident on the diffusion layer 306. However, the light travels in the diffusion layer 306 without being diffused much in the horizontal direction. As a result, light does not reach the observer outside the angle of view of the projection lens, and the observation region R3 is partially narrowed.

  Comparing the partial observation region R3 indicated by the oblique lines in FIG. 11 with the partial observation region R1 of the present embodiment indicated by the oblique lines in FIG. 6, the partial observation region R1 is enlarged, and the observer has a wide area. This is advantageous in that the image can be observed.

<Second Embodiment>
Next, a stereoscopic image display device according to a second embodiment of the present invention will be described. In the following embodiments, the same constituent members as those in the first embodiment will be denoted by the same reference numerals, description thereof will be omitted, and different portions will be mainly described.
[Configuration of stereoscopic image display apparatus]
FIG. 8 is a plan view showing a configuration and a partial observation region of the stereoscopic image display apparatus according to the second embodiment of the present invention.
The stereoscopic image display apparatus 100 of this embodiment is different in that a vertical diffusion screen 101 is provided instead of the vertical diffusion screen 10 of the first embodiment.

  The vertical diffusion screen 101 includes a Fresnel lens 102 and a diffusion plate 103. The diffusion plate 103 is a diffusion plate having diffusion characteristics similar to those of the vertical diffusion screen 10 of the first embodiment. The Fresnel lens 102 is laminated on the projector 61 side of the diffusion plate 103.

[Partial observation region R4]
Light emitted from the projectors 61 to 65 enters the Fresnel lens 102 and is refracted by the Fresnel lens 102. The light is diffused in the vertical direction by the vertical diffusion screen 10 and emitted from the vertical diffusion screen 10 as vertical diffusion light. The light refracted by the Fresnel lens 102 enters the diffusion plate 103, is diffused in the vertical direction by the diffusion plate 103, and is emitted from the diffusion plate 103 as vertical diffused light. At this time, the outgoing light L1 of the projector 61 enters the Fresnel lens 102 with respect to the optical axis K at an incident angle θ (> tan ⁻¹ (W / D)). Therefore, the vertical diffusion light L10 is emitted from the vertical diffusion screen 10 at an emission angle (refraction angle) φ.

Similarly, the outgoing light L3 from the projector 65 enters the Fresnel lens 102 at an incident angle θ (> tan ⁻¹ (W / D)) with respect to the optical axis K. Therefore, the vertical diffused light L11 is emitted from the vertical diffusion screen 10 at an emission angle (refraction angle) φ.
As a result, a partial observation region R4 indicated by diagonal lines in FIG. 8 is generated by the light beams emitted from the projectors 61 to 65.

FIG. 9 is a plan view showing the entire observation area of the stereoscopic image display apparatus 100.
[Full-surface observation region R5]
The outgoing light L5 emitted from the projector 61 enters the Fresnel lens 102 and is refracted by the Fresnel lens 102. The light refracted by the Fresnel lens 102 enters the diffuser plate 103, diffuses in the vertical direction by the diffuser plate 103, and is emitted from the diffuser plate 103 as vertical diffused light L12. At this time, the emission angle φ of the vertical diffused light L12 from the diffusion plate 103 is larger than that in the case where the Fresnel lens 102 is not provided.

  Similarly, the outgoing light L 7 from the projector 65 is refracted by the Fresnel lens 102. The light refracted by the Fresnel lens 102 enters the diffuser plate 103, diffuses in the vertical direction by the diffuser plate 103, and is emitted from the diffuser plate 103 as vertical diffused light L13. At this time, the emission angle φ of the vertical diffused light L13 from the diffusion plate 103 is larger than that in the case where the Fresnel lens 102 is not provided.

  As a result, the entire surface observation region R5 indicated by the oblique lines in FIG. 9 is generated by the light beams emitted from the projectors 61 to 65. The entire observation area R5 is larger than the entire observation area R2 shown in FIG.

[Action etc.]
As described above, according to the present embodiment, the vertical diffusion screen 101 of the stereoscopic image display apparatus 100 includes the Fresnel lens 102 on the projectors 61 to 65 side of the vertical diffusion screen 101. Therefore, light emitted from the projectors 61 to 65 can be refracted by the Fresnel lens 102 and incident on the diffusion plate 103. Specifically, the outgoing light L5 from the projector 61 is refracted by the Fresnel lens 102 and vertically diffused by the diffusion plate 103, and the horizontal outgoing angle φ of the outgoing light L12 from the vertical diffusion screen 101 can be increased. . Further, the outgoing light L7 from the projector 65 can be refracted by the Fresnel lens 102 and vertically diffused by the diffusion plate 103, and the horizontal outgoing angle φ of the outgoing light L13 from the vertical diffusion screen 101 can be increased. As a result, the entire observation region R5 indicated by the oblique lines in FIG. 9 can be enlarged. That is, in the second embodiment, the entire observation region R5 can be enlarged as shown in FIG. 9 while the partial observation region R4 is enlarged as shown in FIG.

FIG. 12 is a plan view showing the entire observation area of the conventional stereoscopic image display apparatus 300 shown in FIG.
A region where light reaches the observer from the entire surface of the vertical diffusion screen 304 of the stereoscopic image display device 300 is a full surface observation region R6 indicated by hatching in FIG. As described above, when the partial observation region R3 shown in FIG. 11 is small, the entire observation region R6 shown in FIG. 12 is also small.

Comparing the entire observation region R6 shown in FIG. 12 with the entire observation region R5 shown in FIG. 9 of the second embodiment, the entire observation region R5 is enlarged, and the observer can observe an image in a wide region. It is advantageous in that it can be performed.
Further, the range of the partial observation region and the range of the entire observation region (for example, the emission angle φ) can be controlled by the focal length of the Fresnel lens 102.

<Third Embodiment>
Next, a stereoscopic image display apparatus according to a third embodiment of the present invention will be described.
FIG. 10 is a plan view showing the configuration of the stereoscopic image display apparatus according to the third embodiment.
In the first embodiment and the second embodiment described above, specific examples of the above-described shift of the projected image are shown.

[Configuration of Projectors 61-65]
The projector 61 includes a spatial light modulation element 61A and a projection lens 61B. Similarly, the projectors 62 to 65 each include a spatial light modulation element and a projection lens.
The projection lenses 61 </ b> B, 62 </ b> B, 63 </ b> B, 64 </ b> B, 65 </ b> B are arranged so that their optical axes K are orthogonal to the light incident surface 10 a of the vertical diffusion screen 10.

The spatial light modulation element 61A is arranged so that the center of the display area of the spatial light modulation element 61A is eccentric (shifted) in the horizontal direction with respect to the optical axis K of the projection lens 61B. The spatial light modulation element 62A is arranged so that the center of the display area of the spatial light modulation element 62A is eccentric with respect to the optical axis K of the projection lens 62B in the horizontal direction by the eccentricity S2. Similarly, the spatial light modulation element 65A is arranged so that the center of the display area of the spatial light modulation element 65A is decentered by the eccentric amount S1 with respect to the optical axis K of the projection lens 65B. The direction in which the spatial light modulator 65A shifts with respect to the projection lens 65B is opposite to the direction in which the spatial light modulator 61A shifts with respect to the projection lens 61B. Similarly, the spatial light modulation element 64A is arranged so that the center of the display area of the spatial light modulation element 64A is decentered by the eccentric amount S2 with respect to the optical axis K of the projection lens 64B. The direction in which the spatial light modulation element 64A shifts with respect to the projection lens 64B is opposite to the direction in which the spatial light modulation element 62A shifts with respect to the projection lens 62B.
The eccentric amounts S1 and S2 are selected so that the projected images from the projectors 61, 62, 64, and 65 coincide on the vertical diffusion screen 10. That is, the eccentric amount S1 is larger than the eccentric amount S2.

[Action etc.]
According to such a configuration, the light emitted from the spatial light modulation element 61A of the projector 61 enters the projection lens 61B from the outside in the horizontal direction, so that the incident angle of the light with respect to the vertical diffusion screen 10 is increased. In addition, the light emission angle from the vertical diffusion screen 10 can be further increased. Therefore, the observation area by the observer can be made larger. The same applies to the projector 65.

Further, the position of the optical axis K of the projector 62 is not the outside in the horizontal direction of the vertical diffusion screen 10 but the inside, but the spatial light modulation element 62A is shifted to the outside in the horizontal direction with respect to the projection lens 62B. For this reason, since the light emitted from the spatial light modulation element 62A is incident on the projection lens 62B from the outside in the horizontal direction, the incident angle of the light with respect to the vertical diffusion screen 10 is increased, and the light from the vertical diffusion screen 10 is increased. The light emission angle can be increased. That is, in the projector 62, the light emitted from the projector 62 satisfies θ> tan ⁻¹ (W / D) due to the shift of the spatial light modulation element 62A. Therefore, the observation area by the observer can be made larger. The same applies to the projector 64.

In addition, embodiment which concerns on this invention is not limited to embodiment described above, Other various embodiment can be considered.
For example, in the said 1st-3rd embodiment, the stereoscopic image display apparatuses 1,100, and 200 showed the example provided with the five projectors 61-65, respectively. However, the number of projectors is not limited to this, and the image quality of a stereoscopic image may be improved by increasing the number of projectors and increasing the number of light beams emitted from the projector. That is, since the projectors 61 to 65 correspond to one pixel in the stereoscopic image, a high-quality stereoscopic image can be obtained by increasing the number of projectors as projection elements as much as possible.

In the first embodiment and the like, the light beams of the projectors 61 and 65 at both ends among the plurality of projectors 61 to 65 arranged in the horizontal direction are arranged at positions satisfying θ> tan ⁻¹ (W / D). An example is shown. However, the present invention is not limited to this, and for example, the projectors may be arranged such that the optical axes coincide with each other in the horizontal direction of the projectors 61 and 65. Light rays emitted from projectors outside the projectors 61 and 65 in the horizontal direction satisfy θ> tan ⁻¹ (W / D). Thereby, a part of observation area can be made larger. Further, one of the light beams of the projectors 61 or 65 at both ends may be arranged at a position satisfying θ> tan ⁻¹ (W / D). In this way, various observation areas can be realized.

  In the first embodiment and the second embodiment, the images projected from the projectors 61, 62, 64, 65 other than the center are respectively aligned with the light incident surface 10 a of the vertical diffusion screen 10. An example in which the position of the projected image in the horizontal direction is shifted is shown. Although it is preferable that the stereoscopic image display apparatuses 1 and 100 have a configuration that realizes such a shift, it is not always necessary.

  In the third embodiment, the projectors 61 and 65 are disposed outside the vertical diffusion screen 10 in the horizontal direction, the spatial light modulation element 62A is eccentric in the horizontal direction with respect to the projection lens 62B, and the projection lens 64B. In this example, the spatial light modulation element 64A is eccentric in the horizontal direction. However, the projectors 61 and 65 at both ends may be omitted, and a plurality of projectors may be arranged so that the projectors 62 and 64 become projectors at both ends. Even in this case, the horizontal observation region by the observer can be enlarged by the light beams from the projectors 62 and 64.

D Projection depth K Optical axis R1, R4 Partial observation region R2, R5 Full-surface observation region S1, S2 Eccentricity W Vertical diffusion screen width θ Incident angle 1, 100, 200 Stereoscopic image display device 61, 62, 63, 64 , 65 Projector 10, 101 Vertical diffusion screen 10a Light incident surface 61A, 62A, 63A, 64A, 65A Spatial light modulator 61B, 62B, 63B, 64B, 65B Projection lens 102 Fresnel lens 103 Diffuser

Claims (5)

A plurality of projectors each having a spatial light modulation element that spatially modulates incident light and a projection lens that projects light from the spatial modulation element;
A light incident surface on which light projected from the projector is incident, and a screen that diffuses incident light more in the vertical direction than in the horizontal direction,
The plurality of projectors are disposed at equidistant positions in the optical axis direction from the light incident surface of the screen, with the optical axis directions of the projection lenses being aligned with the direction orthogonal to the light incident surface. ,
The horizontal width of the screen is W, the projection depth, which is the distance between the projector and the screen in the optical axis direction, is D, and the incident angle of light rays from the projector on the horizontal plane is θ. Sometimes, a stereoscopic display device in which light rays from at least one projector satisfy θ> tan ⁻¹ (W / D). The stereoscopic display device according to claim 1,
The at least one projector is provided so that an optical axis of a projection lens of the projector is positioned on the outer side in the horizontal direction of the screen. The stereoscopic display device according to claim 2,
The projectors disposed at both ends in the horizontal direction are provided such that the optical axes of the projection lenses of the respective projectors are positioned outside the horizontal direction of the screen. The stereoscopic display device according to claim 3,
The screen is a stereoscopic display device having a Fresnel lens provided on the light incident surface side in the optical axis direction. The stereoscopic display device according to claim 4,
The spatial light modulation element of the projector that projects a light beam satisfying θ> tan ⁻¹ (W / D) is such that the center of the display area of the spatial light modulation element is horizontal with respect to the optical axis of the projection lens of the projector. 3D display device arranged to be eccentric.

Images