JP2005284207A - Three-dimensional display device equipped with afocal optical system having opening array - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional display device equipped with an afocal optical system having an opening array capable of reducing fluctuation of optical intensity to the horizontal display direction by smoothly switching a horizontal display angle range of an image by providing an opening means for controlling the horizontal display direction installed in a multiplex image formation system. <P>SOLUTION: In the three-dimensional display device equipped with the afocal optical system having the opening array, the opening means for minimizing change of the optical intensity to the horizontal display direction of a three-dimensional image in the opening array is provided. The opening means is considered as a deformed opening 3 of a parallelogram whose opposite edge facing the horizontal direction of the opening array is inclined to a vertical line. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a three-dimensional display device including an afocal optical system having an aperture array.

  The inventor of the present application has already made it possible to display more images in the horizontal direction, and eliminate the skipping of the images by creating overlapping display angle ranges between the images having the adjacent horizontal display directions. (Refer to Patent Document 1 below).

  FIG. 9 is a block diagram (part 1) of the conventional stereoscopic display device. FIG. 9A is a schematic diagram of the whole, FIG. 9B is a plan view of the two-dimensional image display device array, and FIG. FIG. 9C is a plan view of the lens array, and FIG. 9D is a plan view of the aperture array. FIG. 10 is a configuration diagram (part 2) of the stereoscopic display device. FIG. 10 (a) is a schematic diagram showing the horizontal section, and FIG. 10 (b) is a schematic diagram showing the vertical section.

  In these figures, 110 is a two-dimensional image display device array, 111 is an individual two-dimensional image display device, 112 is a lens array, 113 is an individual lens, 114 is an aperture array, 115 is an individual aperture, and 116 is a shared lens. Reference numeral 117 denotes a vertical diffusion plate, 118 denotes a common image plane, and 119 denotes an optical axis.

  Here, multiple images are displayed in screen units. That is, the imaging system is two-dimensionally arranged to generate a plurality of images having different display directions in the horizontal direction and the vertical direction, and the vertical diffusion plate 117 eliminates the difference in the vertical display direction. By arranging the imaging systems so that all the images have different horizontal display directions, it is possible to generate as many images with different display directions in the horizontal direction as the number of imaging systems.

  More specifically, as shown in the horizontal sectional view of FIG. 10A and the vertical sectional view of FIG. 10B, a plurality of afocal optical systems are multiplexed. A normal afocal optical system is composed of two lenses. In this embodiment, a plurality of afocal optical systems are multiplexed by using a single shared lens 116 in which the image side lens is shared. A two-dimensional image display device 111 is arranged on the object plane of each afocal optical system. Each two-dimensional image display device displays a two-dimensional image obtained by projecting a three-dimensional object in different horizontal directions. All the images of the afocal optical system are formed at the same position on the common image plane 118. The horizontal display direction and the vertical display direction of the image on the common image plane 118 are determined according to the horizontal distance and the vertical distance with respect to the optical axis 119 of each afocal imaging system. Since the afocal optical system is two-dimensionally arranged so that the horizontal positions do not match, all images are displayed in different directions in the horizontal direction. Further, since the light is diffused in the vertical direction by the vertical direction diffusion plate 117, the difference in the vertical display direction of the image is eliminated. Therefore, all images are displayed in different horizontal directions.

In addition, in a 3D display device without glasses that uses a large-diameter convex lens, the discontinuity of the exit pupil at the time of 3D image playback, which has been difficult to eliminate in the past, is eliminated, and a high-quality parallax image does not appear. A stereoscopic image display device capable of observing a high-quality stereoscopic image is disclosed (see Patent Document 2 below).
Japanese Patent Laid-Open No. 2003-140083 JP-A-8-240788

  However, in the conventional three-dimensional display method using a multiple imaging system with a modified two-dimensional arrangement, the aperture that controls the horizontal display direction installed in the multiple imaging system is rectangular, and aberrations of the optical system, etc. Due to the deviation from the ideal imaging state, the change in light intensity with respect to the horizontal display direction is a problem.

  FIG. 11 is a diagram showing an aperture array in a three-dimensional display system using a multiple imaging system having a conventional rectangular aperture and the light intensity with respect to the horizontal display direction of the three-dimensional image.

  In this figure, each rectangular array of openings 202 (corresponding to 115 in FIGS. 9 and 10) is formed in the opening array 201 (corresponding to 114 in FIGS. 9 and 10).

  Since it is configured in this manner, the relationship between the horizontal display direction of the image passing through one opening 202 shown in FIG. 11A and the light intensity of the image is as shown in FIG. The horizontal traveling direction of a light beam for displaying an image is represented by θ. Thus, the horizontal display angle region has a staircase shape corresponding to the horizontal width of the opening 202. Therefore, as shown in FIG. 11C, the horizontal width and horizontal interval of the opening 202 are determined. FIG. 11D shows the horizontal display angle ranges of the images that have passed through the respective apertures. The intensity of the three-dimensional image, which is a combination of these images, with respect to the horizontal display direction is the horizontal created by the respective apertures 202. As a composition of the display angle region, these are added together as shown in FIG. Thus, in an ideal situation, there is no change in intensity in the horizontal display direction of the three-dimensional image.

  Here, let us consider a case where the horizontal display angle range of each image differs from the design value due to the aberration of the imaging system and the manufacturing error of the aperture.

  FIG. 12 is a diagram showing an intensity change depending on the display direction due to a deviation from the conventional ideal imaging system.

  When the horizontal display angle region becomes larger than the design value, the overlap increases in a certain horizontal display direction, and the intensity of light in the horizontal direction increases rapidly as shown in FIG. Further, when the horizontal display angle region is reduced, the overlap is reduced in a certain horizontal display direction, and the intensity of light in the horizontal direction is rapidly reduced as shown in FIG. In either case, the light intensity with respect to the horizontal display direction of the three-dimensional image changes in a stepped manner, and clear intensity unevenness occurs in the three-dimensional image.

  In view of the above situation, the present invention provides an aperture means for controlling the horizontal display direction installed in the multiple imaging system so that the horizontal display angle range of the image can be switched smoothly, and the light with respect to the horizontal display direction can be switched. It is an object of the present invention to provide a three-dimensional display device including an afocal optical system having an aperture array that can reduce fluctuations in intensity.

In order to achieve the above object, the present invention provides
[1] A three-dimensional display device including an afocal optical system having an aperture array, wherein the aperture array is provided with aperture means that can suppress a change in light intensity with respect to a horizontal display direction of a three-dimensional image. .

  [2] In the three-dimensional display device provided with the afocal optical system having the aperture array as described in [1], the aperture means has a deformation in which opposing edges facing the horizontal direction of the aperture array are inclined with respect to a vertical line. It is an opening.

  [3] A three-dimensional display device including an afocal optical system having the aperture array according to [2], wherein the deformed aperture is a parallelogram.

  [4] A three-dimensional display device including an afocal optical system having the aperture array according to [2], wherein the deformed aperture is a hexagon.

  [5] A three-dimensional display device including an afocal optical system having the aperture array according to [2], wherein the deformed aperture is trapezoidal.

  [6] A three-dimensional display device including an afocal optical system having the aperture array according to [2], wherein the deformed aperture is a rhombus.

  [7] In the three-dimensional display device provided with the afocal optical system having the aperture array described in [1], the aperture means is a transparent plate whose transmittance changes in the horizontal direction of the aperture array. .

  [8] In the three-dimensional display device provided with the afocal optical system having the aperture array according to [7], the transparent plate changes the thickness of the metal film by depositing metal on the surface of the transparent plate. Thus, the transmittance is controlled.

  [9] In the three-dimensional display device provided with the afocal optical system having the aperture array according to [7], the transparent plate forms a fine opaque dot pattern on the surface of the transparent plate, The transmittance is controlled by changing the size of the dots.

  [10] In the three-dimensional display device provided with the afocal optical system having the aperture array according to [1], the aperture means divides one aperture into a plurality of portions, and transmits and blocks each of the divided apertures. It is a shutter that can control transmission independently.

  According to the present invention, in the three-dimensional display device provided with the afocal optical system having the aperture array, the aperture array is provided with aperture means that can suppress a change in light intensity with respect to the horizontal display direction of the three-dimensional image. Therefore, the intensity unevenness with respect to the horizontal display direction of the three-dimensional image can be reduced.

  Further, the aperture means can be a transparent plate, and the transmittance can be changed in the horizontal direction of the aperture array.

  Furthermore, the number of images that can be displayed in the multiple imaging system can be increased by dividing the openings in the horizontal direction and replacing the divided openings with shutters.

  The aperture that controls the horizontal display direction installed in the multiple imaging system is deformed from the conventional rectangular shape, for example, a deformed aperture in which the opposed edges facing the horizontal direction of the aperture array are inclined with respect to the vertical line. Let it be a parallelogram. In the case of a rectangular aperture, the horizontal display angle range of a large number of images constituting a three-dimensional image has been switched abruptly. However, when a deformed aperture is used, the horizontal display angle range of the image can be switched smoothly. Variation in light intensity can be reduced.

  Hereinafter, embodiments of the present invention will be described in detail.

  FIG. 1 is a schematic view showing an aperture and a horizontal display direction of an image of a three-dimensional display device provided with the afocal optical system of the present invention. Here, one imaging system is shown out of a number of imaging systems constituting a multiple imaging system arranged in a modified two-dimensional manner.

  In this figure, 1 is a two-dimensional image display device, 2 is a first lens, 3 is an aperture of an aperture array, 4 is a second lens (shared lens), 5 is a vertical diffusion plate, 6 is an image plane, 7 Indicates the central axis of the second lens 4.

  Thus, in the three-dimensional display device provided with this afocal optical system, the image displayed on the two-dimensional image display device 1 is formed on the vertical diffusion plate 5 that is the image plane 6. The two-dimensional image display device 1 is disposed at one of the two focal positions of the first lens 2, and the aperture 3 of the aperture array is disposed at the other. The aperture 3 of the aperture array is disposed at one of the two focal positions of the second lens (shared lens) 4 and the vertical diffusion plate 5 is disposed at the other. As described above, in the afocal optical system in which one of the focal positions of the two lenses 2 and 4 is matched, the angular range of the light beam for displaying the image is controlled by installing the aperture 3 of the aperture array at the matching position. can do.

  The horizontal display direction of the image is determined by the horizontal distance that the aperture 3 corresponding to the combination of the two-dimensional image display device 1 and the first lens 2 has with respect to the central axis 7 of the second lens. Further, since the opening has a width in the horizontal direction, the image is not displayed in a single horizontal display direction, but is displayed in a horizontal display angle region corresponding to the horizontal width of the opening 3.

  FIG. 2 is a diagram showing an aperture array having a modified aperture of the 3D display device according to the embodiment of the present invention and the light intensity with respect to the horizontal display direction of the 3D image.

  Here, what was conventionally a rectangular-shaped opening is, for example, a parallelogram that is a deformed opening whose opposing edges that face in the horizontal direction H are inclined with respect to the vertical line as shown in FIG. Let it be an opening 12. With this configuration, the light intensity in the horizontal display direction changes gently as shown in FIG. 2B in accordance with the change in the vertical width of the opening with respect to the horizontal direction H of the opening. In the deformed opening, the vertical width of the opening becomes smaller toward the periphery, so that the amount of transmitted light becomes smaller toward the periphery. Accordingly, the light intensity distribution in the horizontal direction is also a trapezoidal distribution in which the light intensity decreases in the peripheral portion as shown in FIG. The horizontal display angle range of the plurality of images is as shown in FIG. 2D, and the intensity of the three-dimensional image obtained by superimposing these images in the horizontal display direction H can be made constant as shown in FIG. it can.

  In this way, when a deformed aperture whose opposing edge facing the horizontal direction H is inclined with respect to the vertical line is used, the horizontal display angle range of each image differs from the design value due to aberrations in the imaging system or aperture fabrication errors. Even in such a case, the intensity change of the three-dimensional image with respect to the horizontal display direction H can be suppressed to be small. Therefore, the intensity unevenness of the three-dimensional image with respect to the horizontal display direction H can be reduced.

  FIG. 3 is a diagram showing the intensity change in the display direction due to the deviation from the ideal imaging system by the aperture array having the deformed aperture of the three-dimensional display device of the present invention, and the horizontal display angle region that one aperture bears is designed. The case where the value is larger than the value is shown in FIG. 3A, and the case where the horizontal display angle region is small is shown in FIG.

  Further, the shape of the opening may be a deformed opening in which the opposite edge facing the horizontal direction H is inclined with respect to the vertical line. Therefore, in addition to the parallelogram 12 shown in FIG. 2, as shown in FIG. Various shapes such as a hexagonal opening 13, a trapezoidal opening 14 as shown in FIG. 5, and a rhombus opening 15 as shown in FIG. 6 are conceivable.

  Further, instead of using an opening whose opposing edge facing the horizontal direction H is inclined with respect to the vertical line, the same effect can be obtained by using a transparent plate 21 whose transmittance changes in the horizontal direction as shown in FIG. Can be obtained. This change in transmittance can also be controlled by, for example, depositing metal on the transparent substrate surface and changing the thickness of the metal film. The transmittance can also be controlled by forming a fine opaque dot pattern on the surface of the transparent substrate and changing the dot density and the dot size.

  FIG. 8 is a view showing an aperture in which one aperture is divided into a plurality of apertures, and the transmission and non-transmission of each of the divided apertures are replaced with a shutter that can be controlled independently for each of the divided apertures.

  As shown in FIG. 8 (a), one opening 31 is divided into two parts and replaced with a shutter that can control transmission and non-transmission of the divided individual openings 32 and 33 independently. In this case, the divided openings 32 and 33 are in charge of different horizontal display directions. For example, the divided openings 32 are controlled to be transmissive and the other divided openings 33 are controlled to be non-transmissive, and an image corresponding to the horizontal display direction of the divided openings 32 in the transmissive state is displayed on the two-dimensional image display device. . By controlling in this way, it becomes possible to display a plurality of images in different horizontal directions with one imaging system, and a large number of images can be displayed without increasing the number of imaging systems constituting the multiple imaging system. It becomes possible to display.

  Although FIG. 8A shows the openings 32 and 33 divided into two, FIG. 8B shows the openings 42 to 45 obtained by dividing one opening 41 into four.

  The divided opening needs to have a function as a shutter for switching between the transmission state and the non-transmission state. The switching frequency between the transmission state and the non-transmission state requires a value obtained by multiplying the video rate (30 Hz) by the number of divisions of the aperture, and high-speed switching is required. As such a high-speed shutter device, a ferroelectric liquid crystal panel can be used in addition to a mechanical shutter. The two-dimensional image display device also needs to switch images at the same frequency. As such a high-speed two-dimensional image display device, a ferroelectric liquid crystal display or DMD (Digital Mirror Device) can be used.

  Moreover, since it comprised as mentioned above, the improvement of the image quality of a three-dimensional image display apparatus can be aimed at. In particular, according to the divided opening, it is possible to reduce the size and the price of the three-dimensional image display device.

  In addition, this invention is not limited to the said Example, Based on the meaning of this invention, a various deformation | transformation is possible and these are not excluded from the scope of the present invention.

  The three-dimensional display device provided with the afocal optical system having the aperture array of the present invention can be used as a miniaturized three-dimensional display device with improved image quality.

It is a schematic diagram which shows the opening of a three-dimensional display apparatus provided with the afocal optical system of this invention, and the horizontal display direction of an image. It is a figure which shows the light intensity with respect to the horizontal display direction of the aperture array which has a deformation | transformation opening of the three-dimensional display apparatus which shows the Example of this invention, and a three-dimensional image by it. It is a figure which shows the intensity | strength change by the display direction resulting from the shift | offset | difference from the ideal imaging system by the aperture array which has a deformation | transformation aperture of the three-dimensional display apparatus of this invention. It is a figure which shows the modification (the 1) of the deformation | transformation opening of the three-dimensional display apparatus of this invention. It is a figure which shows the modification (the 2) of the deformation | transformation opening of the three-dimensional display apparatus of this invention. It is a figure which shows the modification (the 3) of the deformation | transformation opening of the three-dimensional display apparatus of this invention. It is a figure which shows the transparent board from which a transmittance | permeability changes in the horizontal direction instead of the opening of the three-dimensional display apparatus of this invention. It is a figure which shows the example which divides | segments into several and controls the opening of the three-dimensional display apparatus of this invention. It is a block diagram (the 1) of the conventional stereoscopic display apparatus. It is a block diagram (the 2) of the conventional stereoscopic display apparatus. It is a figure which shows the light intensity with respect to the horizontal display direction of the aperture array by the three-dimensional display system using the multiple image formation system which has the conventional rectangular-shaped opening, and a three-dimensional image by it. It is a figure which shows the intensity | strength change by the display direction resulting from the shift | offset | difference from the conventional ideal image formation system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Two-dimensional image display apparatus 2 1st lens 3 Aperture of opening array 4 2nd lens (shared lens)
5 Vertical diffusion plate 6 Image plane 7 Center axis of second lens 11 Aperture array 12 Parallelogram aperture 13 Hexagon aperture 14 Trapezoid aperture 15 Rhombus aperture 21 Transparent plate 31 whose transmittance changes in the horizontal direction 41 One opening 32, 33, 42 to 45 Individual openings divided

Claims (10)

  A three-dimensional display device having an afocal optical system having an aperture array, wherein the aperture array is provided with aperture means capable of suppressing a change in light intensity with respect to a horizontal display direction of a three-dimensional image. A three-dimensional display device having an afocal optical system.   2. A three-dimensional display device comprising an afocal optical system having an aperture array according to claim 1, wherein the aperture means is a deformed aperture whose opposing edges facing the horizontal direction of the aperture array are inclined with respect to a vertical line. A three-dimensional display device comprising an afocal optical system having an aperture array characterized by   3. A three-dimensional display device comprising an afocal optical system having an aperture array according to claim 2, wherein the deformed aperture is a parallelogram. apparatus.   3. A three-dimensional display device comprising an afocal optical system having an aperture array according to claim 2, wherein the deformed aperture is hexagonal. .   3. A three-dimensional display device comprising an afocal optical system having an aperture array according to claim 2, wherein the deformed aperture is trapezoidal.   3. A three-dimensional display device comprising an afocal optical system having an aperture array according to claim 2, wherein the deformed aperture is a rhombus.   3. A three-dimensional display device having an afocal optical system having an aperture array according to claim 1, wherein the aperture means is a transparent plate whose transmittance changes in the horizontal direction of the aperture array. A three-dimensional display device with an afocal optical system.   8. A three-dimensional display device comprising an afocal optical system having an aperture array according to claim 7, wherein the transparent plate is formed by depositing a metal on the surface of the transparent plate and changing the thickness of the metal film. A three-dimensional display device provided with an afocal optical system having an aperture array.   8. A three-dimensional display device comprising an afocal optical system having an aperture array according to claim 7, wherein the transparent plate forms a fine opaque dot pattern on the surface of the transparent plate, and the dot density and the dot size. A three-dimensional display device comprising an afocal optical system having an aperture array, wherein transmittance is controlled by changing the aperture.   3. A three-dimensional display device having an afocal optical system having an aperture array according to claim 1, wherein the aperture means divides one aperture into a plurality of portions, and transmits and blocks each of the divided apertures independently. A three-dimensional display device comprising an afocal optical system having an aperture array, wherein the shutter is a controllable shutter.

Images