JP4492208B2 - 3D image playback device - Google Patents

Description

  The present invention includes video technology field, amusement field, entertainment field, internet field, information field, multimedia field, communication field, advertising field, advertising field, medical field, art field, education field, design support field, simulation field, virtual reality. The present invention relates to a three-dimensional image reproducing apparatus that enables three-dimensional display used in, for example.

  Conventionally, as means for displaying three-dimensional image information, two images including binocular parallax, a right eye with the right eye, a left eye with the left eye, and a left eye stereoscopic parallel method, glasses with a liquid crystal shutter There are stereoscopes that use different lenses for the right and left eyes, and an anaglyph method that uses binocular parallax pictures with different colors of red and blue to view images through red and blue glasses. However, special glasses and training are required to view 3D images using these methods.

  In recent years, with the development of liquid crystal technology, liquid crystal displays capable of three-dimensional display without using special glasses have been announced one after another. Most of them are three-dimensional image display devices having only a horizontal parallax of a so-called parallax barrier method or lenticular lens method, which are image splitter type glasses-less three-dimensional liquid crystal display elements. In the three-dimensional display device of the parallax barrier method or the lenticular lens method, the image light path is spatially separated and supplied so that the right eye image can be seen from the right eye position and the left eye image can be seen from the left eye position. It is what is generated. Accordingly, image light paths are periodically supplied to the right eye position and the left eye position periodically in the space, and if the position is shifted, the solid is broken. In this way, in principle, since an image including a parallax in the horizontal direction is supplied, there is a problem that a solid is broken if the right eye position and the left eye position are deviated from the horizontal. Therefore, if stereoscopic viewing is performed while maintaining a three-dimensional moving image solid for a long time, it is necessary to fix the right eye position and the left eye position at fixed positions in space.

  For the horizontal right-eye position and left-eye position deviation, there is a method in which the position of the observer's eyes or face is specified by a sensor, and the image optical path is controlled and corrected according to the deviation of the position. Although it has been devised, the apparatus becomes large and inconvenience arises that a marker must be attached to the observer in order to sense the position of the eyes and the position of the face.

In recent years, as a method for solving these problems, M.I. G. The integral photography proposed by Lipmann in 1908 was developed, and instead of the film, a three-dimensional display method using a two-dimensional display panel such as liquid crystal and a pinhole or fly-eye lens array is, for example, ( This is proposed in Patent Document 1).
JP 2001-275134 A

  However, in order to display smooth three-dimensional images with integral photography, it is necessary to arrange different parallax images in one pinhole or lens. For example, to express 5 parallax images in the horizontal and vertical directions, 25 images of 5 × 5 are required. Accordingly, there is a problem that the resolution of the two-dimensional display panel is reduced to 1 / 25th resolution when performing three-dimensional display.

  There is a method of reducing the number of parallax images in order to prevent such a decrease in resolution, but as the number of parallax images decreases, the smooth parallax does not move and the stereoscopic effect decreases.

  SUMMARY An advantage of some aspects of the invention is to provide a three-dimensional image reproducing apparatus capable of improving resolution, image quality, and stereoscopic effect.

  In order to solve the above-described problems, the present invention provides a three-dimensional image display device that displays three-dimensional image information by two-dimensional display and has a light path control mechanism between a human retina and a three-dimensional image. A diffusion volume hologram screen is provided as a means for projecting a light beam including a plurality of three-dimensional images onto a two-dimensional surface in the vicinity of the imaging plane on the optical path of the light beam including information. In addition, the three-dimensional image reproducing device is characterized in that the light scattered by the diffusion volume hologram screen reaches the retina of the observer.

  According to the present invention, it is possible to realize a three-dimensional image reproduction device that can improve spatial resolution, improve image quality, and increase stereoscopic effect.

  A first invention of the present application is a three-dimensional image display device that displays three-dimensional image information by two-dimensional display and has a light path control mechanism between the human retina and includes three-dimensional image information. In addition to the light beam that directly reaches the retina of the observer, a diffusion volume hologram screen is provided as a means for projecting a light beam including a plurality of three-dimensional images on the two-dimensional surface in the vicinity of the imaging plane on the optical path of the light beam. The three-dimensional image reproducing device is characterized in that light scattered by the diffusion volume hologram screen reaches an observer's retina.

  In addition to the light directly reaching the retina, the light scattered by the diffusive volume hologram screen reaches the viewer's retina, which is recognized as a new parallax image by the viewer and improves the spatial resolution. The image quality of the image is improved and the stereoscopic effect is amplified.

  A convex lens array can be used as the optical path control mechanism of the light beam, and a pinhole array can also be used.

  It is preferable to display the three-dimensional image information using a display element having a resolution of 200 dpi or more. As a result, the reproduction element image 10 of one lens can be composed of an image of 10 × 10 pixels, and a smooth three-dimensional stereoscopic image with 10 fields of view in the horizontal and vertical directions can be reproduced.

  As this display element, a liquid crystal panel, a plasma display panel, or an organic EL panel can be used.

  Refractive index distributed in the volume by using a volume hologram screen as a means to project a light beam including multiple 3D images onto a 2D surface in the vicinity of the imaging plane on the optical path of the light beam including 3D image information Since the light is diffracted by the fluctuation distribution, a clear image can be formed when the light hits it.

  A photopolymer can be used as the material of the diffusion volume hologram screen, and photosensitive gelatin can also be used.

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

FIG. 1 is an explanatory diagram of a 3D image reproduction apparatus according to an embodiment of the present invention. As a method of displaying 3D image information in this 3D image reproducing apparatus, an integral photography method is adopted, and each parallax image of the display element 3 for displaying the horizontal / vertical parallax image 2 and the horizontal / vertical parallax image 2 is used. Is formed in a space, a convex lens array 5 in which the convex lenses 4 are assembled in a planar shape is provided. The three-dimensional image information formed at the imaging point 6 near the focal point of the convex lens 4 enters the observer's eye 7 and becomes a three-dimensional stereoscopic image including a plurality of horizontal and vertical parallaxes.

  Here, the integral photography method will be described in detail. FIG. 2 is an explanatory diagram of the integral photography system. Integral photography G. It was proposed by Lipmann in 1908. The principle is that a fly-eye convex lens array is used to place a film at the focal point of the fly-eye convex lens array, and the fly-eye shape on the surface of the film. When an image for each convex lens is recorded and reproduced, a stereoscopic image is reproduced by using the same fly-eye convex lens array as that used for photographing the image for each fly-shaped convex lens recorded on the film. .

  As shown in FIG. 2, when the display element 9 for displaying the reproduction element image 8 is displayed corresponding to each convex lens 11 of the fly-shaped convex lens array 10, the reproduction element image 8 passes through the convex lens 11. An image is formed at an imaging point 12 corresponding to the pixel position on the original image surface. Therefore, when viewed from the observer, a light beam 13 is actually generated from the image forming point 12 and is incident on the pupil 14 of the observer, whereby a three-dimensional reproduced image 15 having a stereoscopic effect is reproduced. Since the three-dimensional reproduced image 15 having a three-dimensional effect actually has an image point 12 in the space, the three-dimensional reproduced image 15 having a three-dimensional effect can be stabilized even if the angle is changed or the position of the eye is moved. You can see it.

  A liquid crystal panel is used as the display element 3 used in the three-dimensional image reproducing apparatus of FIG. In the present embodiment, a convex lens 4 having a diameter of 1.5 mm is used, and a liquid crystal panel which is a display element 3 for displaying a horizontal / vertical parallax image 2 has a resolution of 200 dpi. As a result, the reproduction element image 8 of one lens is composed of an image of 10 × 10 pixels, and a smooth three-dimensional stereoscopic image with 10 fields of view in the horizontal and vertical directions can be reproduced. When the resolution of the liquid crystal panel as the display element 3 is 200 dpi or less, it is difficult to obtain a natural three-dimensional reproduced image. Although it is a trade-off with data processing time, it is effective to reproduce the reproduction element image 8 having a resolution of 200 to 700 dpi with a lens of 1.5 mm or less in order to obtain a natural three-dimensional stereoscopic image. Of course, a plasma display panel and an organic EL panel can be used in addition to the liquid crystal panel as means for displaying the reproduction element image 8.

  A diffusion volume hologram screen 1 is provided in the vicinity of the imaging point 6 of the convex lens 4 as means for projecting a light beam including a plurality of three-dimensional images onto a two-dimensional surface. With reference to FIG. 3, an explanatory view of the effect of the diffusion volume hologram screen according to the embodiment of the present invention will be described in detail. As shown in FIG. 3, the horizontal / vertical parallax image 2 of the display element 3 is formed at an image point 18 near the focal length of the convex lens 4 by the convex lens 4 immediately above the corresponding horizontal / vertical parallax image 2 in the convex lens array 5. Although the image is formed, since the light ray 16 incident on the observer's eye 7 in a straight line from the position of the image formation point 18 is one light beam corresponding to each convex lens 4, the resolution depends on the diameter of the convex lens array 5. Will drop. However, by installing the diffusion volume hologram screen 1 for scattering the light beam 17 that does not directly enter the observer's eye near the imaging point 18, the light beam 17 that does not directly enter the eye is scattered. 19a and 19b. Among the light ray groups 19a and 19b, the light ray 19a incident on the observer's eyes is recognized as a new parallax image by the observer, thereby improving the spatial resolution, thereby improving the image quality of the apparent image and improving the stereoscopic effect. Is amplified.

Examples of the diffuser plate that scatters the light beam 17 that is not directly incident on the eyes include rubbed glass, a diffusion sheet in which a plastic surface is processed to be uneven, and a hologram diffusion sheet in which an embossed hologram process is applied to the plastic surface. These diffuser plates form an image by randomly scattering light by the surface of the uneven structure of the material, so that the image is totally blurred due to noise of scattered light. However, since the diffusion type volume hologram screen 1 diffracts light by the variation distribution of the refractive index distributed in the volume, it is normally transparent but can form a clear image when it hits the light.

  The hologram element used for the diffusion volume hologram screen 1 of the present invention is manufactured by recording a diffuser 21 on a photosensitive member 22 such as a photopolymer by an exposure optical system 20 as shown in FIG.

  In this manufacturing method, laser light 24 (for example, wavelength 532 nm) emitted from a laser oscillator 23 (for example, Nd: YAG laser) is split in two directions by a beam splitter 25. One light passes through two reflecting mirrors 26, becomes divergent light by an expander 27, and is then projected onto the photosensitive member 22 as reference light 28. The other light also passes through the two reflecting mirrors 29 and becomes divergent light by the expander 30 and is then introduced into the parabolic mirror 31. The light reflected by the parabolic mirror 31 passes through the diffuser 21 and becomes diffused light, and then is projected onto the photosensitive member 22 as object light 32. The diffusion hologram screen using the hologram element manufactured in this way allows light, including light that does not directly reach the retina, to reach the retina, and has high resolution, high image quality, and three-dimensionality. A stereoscopic image can be formed.

  In the above description, the convex lens array is used as the optical path control mechanism of the light beam. However, the present invention is not limited to this, and a pinhole array can also be used. Further, a photopolymer or photosensitive gelatin can be used as a material for the diffusion volume hologram screen.

  The stereoscopic image reproducing apparatus according to the present invention includes a video technology field, an amusement field, an entertainment field, the Internet field, an information field, a multimedia field, a communication field, an advertisement / advertisement field, a medical field, an art field, an education field, and a design support field. It can be used as a 3D display and 3D image reproduction device used in the simulation field, virtual reality, etc.

Explanatory drawing of the three-dimensional image reproduction apparatus which concerns on embodiment of this invention Illustration of the integral photography system Explanatory drawing of the effect of the diffusion type volume hologram screen which concerns on embodiment of this invention Explanatory drawing of the formation method of the diffusion type | mold volume hologram screen which concerns on embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Diffusion type volume hologram screen 2 Horizontal / vertical parallax image 3 Display element 4 Convex lens 5 Convex lens array 6 Imaging point 7 Observer eye 8 Reproduction element image 9 Display element 10 Fly-shaped convex lens array 11 Convex lens 12 Imaging point 13 Ray 14 Observer's pupil 15 Three-dimensional reconstructed image with three-dimensional effect 16 Ray incident on the eye 17 Ray not directly incident on the eye 18 Imaging point 19a Scattered light group 19b Scattered light group 20 Exposure optical system 21 Diffusion Body 22 Photosensitive member 23 Laser oscillator 24 Laser beam 25 Beam splitter 26 Reflector 27 Expander 28 Reference beam 29 Reflector 30 Expander 31 Parabolic mirror 32 Object beam

Claims (9)

A three-dimensional image display device that displays three-dimensional image information by two-dimensional display and has a light path control mechanism between the human retina and a light beam including the three-dimensional image information on the optical path. A diffusion volume hologram screen is provided as a means for projecting a light beam including a plurality of three-dimensional images in the vicinity of the surface onto a two-dimensional surface. In addition to the light beam that directly reaches the retina of the observer, the light is scattered by the diffusion volume hologram screen. A three-dimensional image reproduction device characterized in that the emitted light beam reaches the retina of an observer. The three-dimensional image reproduction device according to claim 1, wherein the display of the three-dimensional image information is performed using a display device having a resolution of 200 dpi or more. The three-dimensional image reproducing apparatus according to claim 2, wherein the display element is a liquid crystal panel. The three-dimensional image reproducing apparatus according to claim 2, wherein the display element is a plasma display panel. The three-dimensional image reproducing apparatus according to claim 2, wherein the display element is an organic EL panel. 2. The three-dimensional image reproducing apparatus according to claim 1, wherein a convex lens array is used as an optical path control mechanism for the light beam. 2. The three-dimensional image reproducing apparatus according to claim 1, wherein a pinhole array is used as an optical path control mechanism for the light beam. The three-dimensional image reproducing apparatus according to claim 1, wherein the material of the diffusion volume hologram screen is a photopolymer. 2. The three-dimensional image reproducing apparatus according to claim 1, wherein the material of the diffusion volume hologram screen is photosensitive gelatin.

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