Display device

Abstract

To provide a display device capable of aerially projecting a three-dimensional image in a suitable condition.SOLUTION: A display device comprises: a space image-forming element which has a flat surface, and image-forms a subject on one face side of the flat surface in the air on the other face side with a rugged relation being inverted; and a three-dimensional display including a display panel which has view point pixels for displaying a plurality of view point images, and a sorting mechanism which sorts light of the view point images of the display panel. The display device aerially image-forms view point image of the three-dimensional display by the space image-forming element. The view point image projected by the three-dimensional display includes in a screen a normal vision region and a reverse vision region. An image obtained by aerially image-forming the view point image using the space image-forming element is provided with an observation position where the whole screen becomes the normal vision region.SELECTED DRAWING: Figure 19

Description

[Technical field]

[0001] The present disclosure relates to a display device that projects a three-dimensional image into the air. [Background technology]

[0002] There is an imaging means that can define a certain plane and image a subject on one side of the plane as a real image in the air on the other side with the concave-convex relationship reversed, and in this specification, such an imaging means is called a spatial imaging element. Known examples of such spatial imaging elements include a device that combines a dihedral corner reflector, a retroreflector array, and a half mirror, and an afocal lens array that uses two microlens arrays, with each lens pair being an afocal system (see, for example, Patent Document 1).

[0003] Furthermore, as three-dimensional displays that project stereoscopic images, displays that employ a lenticular lens system, a parallax barrier system, or the like are known (see, for example, Patent Document 2).

[0004] Furthermore, there is known an image display device that combines the spatial imaging element and the three-dimensional display to project a stereoscopic image into the air (see, for example, Patent Documents 3 and 4). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2008 / 123473 [Patent Document 2] JP 2004-280052 A [Patent Document 3] JP 2016-140056 A [Patent Document 4] JP 2017-10014 A Summary of the Invention [Problem to be solved by the invention]

[0006] As described in Patent Document 3 (paragraphs

[0019] and

[0020] ), when a spatial imaging element is simply combined with a lenticular lens type and a parallax barrier type 3D display, a problem occurs in which 3D normal viewing areas and 3D inverted viewing areas appear alternately on the screen imaged in the air.

[0007] To solve this problem, Patent Document 3 performs image processing to switch 3D display input image data in the area where reverse viewing occurs (paragraph

[0021] ). However, when switching images, if there is parallax at the boundary between the switched images, the boundary is easily visible on the screen imaged in the air, making it difficult to provide a seamless 3D display across the entire screen imaged in the air.

[0008] Patent Document 4 states that the 3D image formed has a relatively wide depth range (paragraph

[0017] ), but there is no definition of the depth range, and it is unclear whether it is wide or narrow.

[0009] Furthermore, paragraphs

[0013] and

[0014] of Patent Document 4 describe a relational expression between the barrier pitch of the parallax barrier and the viewpoint group pitch. However, since the refractive index between the pixel and the parallax barrier is different from that of air, the light passing through the barrier opening through the pixel is refracted at the interface with the air. To achieve a suitable stereoscopic display, a design that takes this refraction into account is necessary, but the relational expression described in Patent Document 4 does not take the refractive index into account. Therefore, an image display device designed based on the relational expression disclosed in Patent Document 4 has difficulty projecting a three-dimensional image into the air as designed. [Means for solving the problem]

[0010] A representative example of the invention disclosed in the present application is as follows: A display device including a spatial imaging element having a plane and forming a real image of a subject on one side of the plane in which the concave-convex relationship is inverted in the air on the other side, a display panel having viewpoint pixels for displaying a plurality of viewpoint images, and a three-dimensional display including a distribution mechanism for distributing the light of the viewpoint images of the display panel, the display device forming the viewpoint images of the three-dimensional display in the air by the spatial imaging element, the viewpoint images projected by the three-dimensional display including a normal viewing area and an inverted viewing area within a screen, And there is no observation position where the entire screen is a normal viewing area or a pseudoscopic viewing area, The image formed in the air by the spatial imaging element from the viewpoint image has an observation position where the entire screen is a normal viewing area. Effect of the Invention

[0011] According to the present disclosure, it is possible to provide a display device that projects a three-dimensional image into the air in an optimal state. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic diagram illustrating a configuration example of an image display device according to the present disclosure. [Diagram 2] FIG. 1 is a diagram showing an outline of an optical model of an image display device according to the present disclosure. [Diagram 3] 1 is a schematic diagram (XY plan view) illustrating a parallax barrier included in a three-dimensional display according to the present disclosure. [Figure 4A] 1 is a perspective view illustrating an example of the structure of an afocal lens array that functions as a spatial imaging element according to the present disclosure. FIG. [Figure 4B] 1 is a perspective view illustrating an example of the structure of an afocal lens array that functions as a spatial imaging element according to the present disclosure. FIG. [Figure 5A] 1A and 1B are diagrams illustrating the operating principle of an afocal lens array. [Figure 5B] 1A and 1B are diagrams illustrating the operating principle of an afocal lens array. [Figure 6A]1A and 1B are diagrams illustrating an example of the structure of a mirror element array that functions as a spatial imaging element according to the present disclosure. [Figure 6B] 1A and 1B are diagrams illustrating an example of the structure of a mirror element array that functions as a spatial imaging element according to the present disclosure. [Figure 7A] 13A to 13C are diagrams illustrating an example of the structure of another mirror element array functioning as a spatial imaging element according to the present disclosure. [Figure 7B] 13A to 13C are diagrams illustrating an example of the structure of another mirror element array functioning as a spatial imaging element according to the present disclosure. [Figure 8] 1A and 1B are diagrams illustrating the operating principle of a mirror element array. [Figure 9A] 1A and 1B are diagrams illustrating the operating principle of a mirror element array. [Figure 9B] 1A and 1B are diagrams illustrating the operating principle of a mirror element array. [Figure 10A] FIG. 2 is a side view illustrating an example of the structure of a retroreflective sheet. [Figure 10B] FIG. 2 is a side view illustrating an example of the structure of a retroreflective sheet. [Figure 11A] 1A and 1B are diagrams illustrating the operating principle of an optical system in which a half mirror and a retroreflective sheet are combined. [Figure 11B] 1A and 1B are diagrams illustrating the operating principle of an optical system in which a half mirror and a retroreflective sheet are combined. [Figure 12] FIG. 1 is a diagram illustrating an optical model of a conventional parallax barrier type three-dimensional display. [Figure 13] FIG. 1 is a diagram illustrating a screen of a conventional parallax barrier type three-dimensional display as viewed by an observer. [Figure 14] FIG. 1 is a diagram illustrating an optical model of a conventional parallax barrier type three-dimensional display. [Figure 15] FIG. 1 is a diagram illustrating a screen of a conventional parallax barrier type three-dimensional display as viewed by an observer. [Figure 16] FIG. 1 is a diagram for explaining an optical model of an image display device that combines a conventional three-dimensional display and a conventional spatial imaging element. [Figure 17] FIG. 1 is a diagram for explaining an optical model of an image display device that combines a conventional three-dimensional display and a conventional spatial imaging element. [Figure 18] FIG. 1 is a diagram illustrating a screen of an image display device that combines a conventional three-dimensional display and a conventional spatial imaging element viewed by an observer. [Figure 19] FIG. 2 is a diagram illustrating an example of an optical model of an image display device according to the present disclosure. [Figure 20] FIG. 2 is a diagram illustrating an example of an optical model of an image display device according to the present disclosure. [Figure 21A] FIG. 13 is a diagram illustrating an optical model of the image display device described in Patent Document 4. [Figure 21B] FIG. 13 is a diagram illustrating an optical model of the image display device described in Patent Document 4. [Figure 22] 1 is a graph showing the relationship between the refractive index n and the number of pixels m and the distance OD. [Figure 23A] 1 is an optical diagram illustrating a single viewpoint image viewing area of ​​an image display device of an arbitrary design. [Figure 23B] 1 is an optical diagram illustrating a single viewpoint image viewing area of ​​an image display device of an arbitrary design. [Figure 23C] 1 is an optical diagram illustrating a single viewpoint image viewing area of ​​an image display device of an arbitrary design. [Figure 24] FIG. 1 is a diagram showing an outline of an optical model of an image display device according to the present disclosure. [Diagram 25] 1 is a schematic diagram (XY plan view) of a lenticular lens included in a three-dimensional display of the present disclosure. [Figure 26] FIG. 2 is a diagram illustrating an example of an optical model of an image display device according to the present disclosure. [Figure 27] FIG. 2 is a diagram illustrating an example of an optical model of an image display device according to the present disclosure. [Figure 28] FIG. 2 is a diagram illustrating an example of an optical model of an image display device according to the present disclosure. [Figure 29] FIG. 1 is a diagram showing an outline of an optical model of an image display device according to the present disclosure. [Diagram 30]FIG. 1 is a diagram showing an outline of an optical model of an image display device according to the present disclosure. [Diagram 31] 1 is a schematic diagram (XY plan view) illustrating a parallax barrier included in a three-dimensional display according to the present disclosure. [Diagram 32] 1 is a schematic diagram (XY plan view) of a lenticular lens included in a three-dimensional display of the present disclosure. [Diagram 33] FIG. 2 is a diagram illustrating an example of an optical model of an image display device according to the present disclosure. [Diagram 34] FIG. 2 is a diagram showing an example of a viewpoint image of an image display device according to the present disclosure. [Figure 35A] 1 is a diagram showing an example of an image seen by both eyes of an observer viewing an image display device according to the present disclosure. [Figure 35B] 1 is a diagram showing an example of an image seen by both eyes of an observer viewing an image display device according to the present disclosure. [Diagram 36] FIG. 2 is a diagram illustrating an optical model of the multi-display of the present disclosure. [Figure 37] 1A and 1B are diagrams showing examples of images seen by both eyes of an observer viewing a multi-image display according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In each drawing, the same reference numerals are used to denote common components.

[0014] [First embodiment] Fig. 1 is a schematic diagram showing a configuration example of an image display device 100 according to the present disclosure. Fig. 2 is a diagram showing an outline of an optical model of the image display device 100 according to the present disclosure.

[0015] Fig. 1 is a perspective view of an image display device 100 according to a first embodiment. Fig. 2 is a diagram showing a cross-sectional structure of the image display device 100 taken along line AA' on the XZ plane, and an optical model.

[0016] For the sake of explanation, the image display device 100 will be described using coordinate axes as shown in Fig. 1. For the sake of simplicity, the coordinate axes are set so that the relationships between the components of the image display device 100 are perpendicular or parallel.

[0017] Image display device 100 is a device that projects a stereoscopic subject (image) into the air, and has a three-dimensional display 101 and a spatial imaging element 102. Aerial image 104 indicates a screen 103 of three-dimensional display 101 that is imaged in the air by spatial imaging element 102. In this disclosure, it is assumed that both eyes of an observer are aligned in the X direction, and that the observer views aerial image 104 in the direction of arrow 105.

[0018] It is assumed that the three-dimensional display 101 and the spatial imaging element 102 are housed in a housing. The housing of the image display device 100 that houses the three-dimensional display 101 and the spatial imaging element 102 may have any shape.

[0019] The three-dimensional display 101 includes a display panel having a plurality of pixels for forming a plurality of viewpoint images, and an optical separation means for spatially separating light emitted from pixels corresponding to each viewpoint image for each viewpoint. As described later, the three-dimensional display 101 of the present disclosure is designed so that the observer can visually recognize the floating image formed by the spatial imaging element as a stereoscopic image in the design of the optical separation means for a predetermined display panel. For this reason, when the observer directly observes the screen of the three-dimensional display 101 of the present disclosure without using the spatial imaging element, normal viewing areas and reverse viewing areas appear alternately on the screen, and the observer cannot easily observe the stereoscopic image. However, for the sake of convenience in this specification, the display panel equipped with this optical separation means is called a "three-dimensional display."

[0020] The three-dimensional display 101 of the first embodiment is a three-dimensional display 101 that employs a parallax barrier as an optical separation means. The three-dimensional display 101 has a display panel 110 and a parallax barrier .

[0021] The display panel 110 is a liquid crystal panel, an LED panel, an OLED panel, etc., and displays a display image including images from different viewpoints (viewpoint images). The display panel 110 is composed of a plurality of pixel units 120 that display pixels of the display image.

[0022] The pixel unit 120 is composed of a plurality of viewpoint pixels (a viewpoint pixel group) that display pixels of each viewpoint image. For example, as shown in Fig. 2, the pixel unit 120 of the display panel 110 is composed of two viewpoint pixels 121 and 122 that are alternately arranged in the X direction. The viewpoint pixel 121 displays a pixel of a viewpoint image of the left eye viewpoint, and the viewpoint pixel 122 displays a pixel of a viewpoint image of the right eye viewpoint. Therefore, in this case, a display image including two viewpoint images is displayed on the display panel 110.

[0023] In this embodiment, the display panel 110 that displays an image including two viewpoint images will be described as an example, but the display panel 110 may display an image including three or more viewpoint images. In this case, the pixel unit 120 is composed of a viewpoint pixel group that displays each pixel of the multiple viewpoint images.

[0024] The parallax barrier 130 is a light-shielding barrier and has slits 131 arranged in a certain pattern. FIG. 3 is a schematic diagram (XY plan view) illustrating the parallax barrier 130 in the center of the three-dimensional display 101 of the present disclosure. The barrier limits the angle of the light beam passing from the viewpoint pixel through the slits. Therefore, by suitably arranging the parallax barrier 130 on the display panel 110, a region where only the viewpoint pixel 121 (viewpoint pixel group) of each pixel unit 120 is visible through the slit 131 and a region where only the viewpoint pixel 122 (viewpoint pixel group) of each pixel unit 120 is visible through the slit 131 are formed. In other words, the parallax barrier 130 with the slits 131 functions as an optical separation means (distribution unit) that distributes a group of light rays emitted from a display image displayed on the display panel 110 into a group of light rays for each viewpoint image. The slits 131 are arranged so that one slit 131 corresponds to one pixel unit 120.

[0025] It should be noted that a switchable liquid crystal (LC) parallax barrier, which can electrically make the light-shielding portion transparent, can be used as the parallax barrier 130. In this case, by making the light-shielding portion transparent, not only a three-dimensional image but also a two-dimensional image can be provided.

[0026] 2, the inside of the three-dimensional display 101 has a refractive index n different from that of air, so that the light rays passing through the slit 131 from the viewpoint pixels 121 and 122 are refracted at the air interface. For example, if the light ray emerging from the left end of the pixel unit 120 located at the center of the display panel 110 and passing through the slit 131 located at the center of the parallax barrier 130 is designated as light ray LCl1 and the incident angle to the slit 131 is designated as α, the light ray LCl1 passing through the slit 131 at the incident angle α is refracted at the air interface and travels toward the spatial imaging element 102 as light ray LCl2 with an exit angle β. Here, the image display device 100 of the present disclosure is designed so that the normal vector of the display surface of the display panel 110 projected onto the XZ plane and the normal vector of the surface S of the spatial imaging element 102 projected onto the XZ plane overlap. Therefore, the light ray LCl2 enters the spatial imaging element 102 at an incident angle β, and is emitted as a light ray LCl3 at an emission angle -β due to the characteristics of the spatial imaging element 102, the details of which will be described later. Note that the clockwise direction is considered to be a positive angle.

[0027] The spatial imaging element 102 is an imaging means that reflects or refracts the light of the subject input from one surface side, and forms an image of the subject in the air on the other surface side as a real image with an inverted concave-convex relationship. Therefore, a group of other light rays that have traveled along a path similar to that of the light ray LCl3 forms a real image on the screen of the three-dimensional display 101 at a position that is plane-symmetrical to the surface S of the spatial imaging element 102 (aerial image 104). Note that the spatial imaging element 102 shown in FIG. 2 does not represent a specific shape, size, or position, but represents a conceptual shape, size, and position.

[0028] For example, an afocal lens array, a mirror element array that causes two reflections, an optical system that combines a retroreflective sheet and a half mirror, etc., can be used as the spatial imaging element 102. Here, the spatial imaging element 102 will be described.

[0029] First, the afocal lens array will be described. Figures 4A and 4B are perspective views illustrating an example of the structure of an afocal lens array 400 that functions as the spatial imaging element 102 of the present disclosure.

[0030] 4A is a combination of two lens arrays 401 and 402, in which element lenses are arranged on a plane, and each element lens on each array surface is paired with an element lens on the opposing surface. The paired element lenses are arranged so that their optical axes are coaxial, and are designed so that the focal points of the element lenses of each of the lens arrays 401 and 402 coincide inside the afocal lens array 400. The surface formed by these focal points is designated as S1.

[0031] As the configuration of the afocal lens array 400, an array that exhibits a lens effect in two directions is preferable, but a so-called lenticular lens, which is an array of cylindrical lenses 411, 412 arranged in one direction as shown in FIG. 4B, can also be applied.

[0032] 5A and 5B are diagrams illustrating the operating principle of the afocal lens array 400. FIG.

[0033] The element lenses of the lens arrays 401 and 402 shown in FIG. 5A are designed to have the same focal length (f1=f2), and therefore the surface S1 is the central plane of the afocal lens array 400 in the Z-axis direction.

[0034] Light rays LOa1, LOb1, LOc1, and LOd1 emitted from the light source O1 are incident on the lens array 401. The light rays LOa1, LOb1, and the light rays LOc1 and LOd1 incident on the element lenses can be considered as parallel light if the distance from the element lens surface to O1 is sufficiently large with respect to the pitch of the element lenses. Therefore, the light rays LOa2, LOb2, and the light rays LOc2 and LOd2 incident on the lens array 401 and refracted intersect at the surface S1, are refracted at the lens array 402, and are emitted as light rays LOa3, LOb3, LOc3, and LOd3. When f1=f2, the incident angle and the exit angle of each light ray are equal, so the light rays LOa3, LOb3, LOc3, and LOd3 gather at a position P1 that is symmetrical to the light source O1 with respect to the surface S1. Therefore, the light source O1 is imaged as a real image at the position P1. Similarly, a light source O2 located at a position farther away from the surface S1 than the light source O1 is focused on a position P2.

[0035] As shown in Figure 5A, the viewer sees the image at position P2 in front of the image at position P1. Therefore, if a three-dimensional object is placed in place of light sources O1 and O2, a real image with the convex-concave relationship of the object reversed is formed in the air at a position symmetrical to the surface S1.

[0036] As described above, the afocal lens array 400 functions as a spatial imaging element 102 that images an object input from one surface side of the surface S1 in the air on the other surface side as a real image with an inverted concave-convex relationship. Note that the relationship between the incident light beam and the outgoing light beam that contribute to the image formation is such that the magnitudes of the incident angle and the outgoing angle with respect to the normal line of the surface S are the same, but the signs are opposite.

[0037] 5B, a real image of the screen 103 is formed at a position symmetrical to the surface S1. An observer can view the formed aerial image 104 from the direction of the arrow 105.

[0038] Next, the mirror element array will be described. Figures 6A and 6B are diagrams for explaining an example of the structure of a mirror element array 600 that functions as the spatial imaging element 102 of the present disclosure. Figure 6A is a plan view of the mirror element array 600 on a UV plane in a UVW coordinate system, and Figure 6B is a partially enlarged perspective view of a region B of the mirror element array 600.

[0039] 6A, the mirror element array 600 has a planar extent in the U-axis and V-axis directions. A large number of diamond-shaped unit optical elements 601 that transmit light from one surface to the other surface (or from the other surface to the one surface) are provided on the planar extent.

[0040] Here, in order to explain the partially enlarged perspective view of region B in Fig. 6B, a three-dimensional orthogonal coordinate system U'V'W is set. The three-dimensional orthogonal coordinate system U'V'W is a coordinate system in which the U and V axes are rotated 45 degrees around the W axis, and the U'V' plane is a plane parallel to the UV plane.

[0041] 6B, the mirror element array 600 has a thickness in the W-axis direction. The unit optical elements 601 are arranged in a matrix along the U'-axis and V'-axis directions. Each unit optical element 601 has inner wall surfaces formed in the W-axis direction that are orthogonal to each other, and each inner wall surface is subjected to a mirror finish.

[0042] 7A and 7B are diagrams illustrating an example of the structure of another mirror element array 700 that functions as the spatial imaging element 102 of the present disclosure. Fig. 7A is a UV plan view of the mirror element array 700, and Fig. 7B is a partially enlarged perspective view of region B of the mirror element array 700.

[0043] As shown in Fig. 7A, mirror element array 700 has a planar spread in the U-axis direction and the V-axis direction, similar to mirror element array 600. To explain the enlarged perspective view of region B, a three-dimensional orthogonal coordinate system U'V'W is set, similar to Fig. 6A.

[0044] As shown in Fig. 7B, the mirror element array 700 has a structure in which a first element 701 having a mirror surface 710 parallel to the V'W plane and a second element 702 having a mirror surface 711 parallel to the U'W plane are closely arranged in the W-axis direction. The first element 701 or the second element 702 is a structure in which a plurality of transparent glass (or acrylic resin) elements having mirror surfaces on the side are closely arranged at equal intervals in the U'-axis or V'-axis direction. Therefore, the mirror element array 700 has a structure in which a large number of diamond-shaped unit optical elements that transmit light from one surface to the other surface are formed in the W-axis direction as shown in Fig. 7A.

[0045] 8, 9A, and 9B are diagrams for explaining the operating principle of the mirror element arrays 600, 700. Here, the operating principle will be explained using the mirror element array 600 as an example, but the mirror element array 700 also operates according to the same operating principle.

[0046] Fig. 8 shows a schematic diagram of the optical path of light emitted from a light source O and focused at a position P when the mirror element array 600 is viewed from the W-axis direction. The solid line indicates the light emitted from the light source, and the dotted line indicates the light reflected on the mirror surface. Fig. 9 is a diagram viewed from the U-axis direction, in which the mirror element array 600 is disposed with the W-axis tilted with respect to the Y-axis. Here, the surface formed in the V-axis direction of the mirror element array 600 and located at the center of the thickness of the mirror element array 600 in the W-axis direction is referred to as surface S2.

[0047] 8, light emitted from a light source O is incident on a mirror element array 600. When the incident light is reflected by two orthogonal mirror surfaces formed on the mirror element array 600, it becomes light traveling in the direction of the dotted arrow.

[0048] In FIG. 8, for the sake of simplicity, the spatial imaging element 102 is shown in a schematic shape, and the actual interval between the orthogonal mirror elements is designed to be sufficiently smaller than the distance from the light source to the spatial imaging element 102. Therefore, when the optical path of the light reflected twice inside the mirror element array 600 is viewed from the W-axis direction, the incident light and the outgoing light almost overlap. Therefore, as shown in FIG. 9A, of the light emitted from the light source O1, the light reflected twice by the mirror surface inside the mirror element array 600 is collected at a position P that is plane-symmetrical to the light source O with respect to the surface S2. Therefore, the light source O1 is imaged as a real image at the position P1. Similarly, the light source O2, which is located at a position farther away from the surface S2 than the light source O1, is imaged at the position P2.

[0049] As shown in Fig. 9A, the observer sees the image at position P2 in front of the image at position P1. Therefore, if a three-dimensional object is placed instead of light sources O1 and O2, a real image with the convex-concave relationship of the object reversed is formed in the air at a position symmetrical to the surface S2.

[0050] As described above, the mirror element array 600 functions as a spatial imaging element 102 that images an object input from one surface side of the surface S2 into a real image in the air on the other surface side with the concave-convex relationship reversed. Note that the relationship between the incident light beam and the outgoing light beam that contribute to the imaging is such that the magnitudes of the incident angle and the outgoing angle with respect to the normal line of the surface S2 are the same, but the signs are opposite.

[0051] 9B, a real image of the screen 103 is formed at a position symmetrical to the surface S2. An observer can view the formed aerial image 104 from the direction of the arrow 105.

[0052] Next, an optical system in which a retroreflective sheet and a half mirror are combined will be described. First, the retroreflective sheet will be described. Figures 10A and 10B are diagrams showing the operation principle of the retroreflective sheet.

[0053] Retroreflective sheets are designed so that, in principle, the angle of incidence of light incident on the sheet surface is equal to the angle of emission of light reflected by a reflective surface inside the sheet and emitted from the sheet surface.

[0054] Fig. 10A is a side view illustrating an example of the structure of a retroreflective sheet 1000. The retroreflective sheet 1000 has a structure in which a plurality of spheres 1001 such as glass beads are arranged. Light incident on the sphere 1001 is refracted at the surface, reflected within the sphere, refracted again at the surface, and emitted from the sphere 1001. Since the incident surface and the reflective surface are spherical, the incident angle and the exit angle are equal. Therefore, the sheet having the structure shown in Fig. 10A functions as a retroreflective sheet that reflects light in the direction in which it entered.

[0055] Fig. 10B is a side view illustrating an example of the structure of another retroreflective sheet 1010. The retroreflective sheet 1010 has a structure in which a plurality of triangular or quadrangular pyramid bases (reflective surfaces 1011, 1012) are arranged in the direction in which light enters. Since the interior angle formed by the reflective surfaces 1011 and 1012 shown in the side view of Fig. 10B is set to 90 degrees, when the incident light is reflected by each of the reflective surfaces 1011 and 1012, it returns in the same direction as the incident direction.

[0056] 11A and 11B are diagrams for explaining the operating principle of an optical system 1100 in which a half mirror 1101 and a retroreflective sheet 1102 are combined.

[0057] Light rays LOa11, LOb11, and LOc11 emitted from the light source O1 are transmitted or reflected by the half mirror 1101. Light rays LOa12, LOb12, and LOc12 reflected by the half mirror 1101 are retroreflected by the retroreflective sheet 1102, and are transmitted or reflected again by the half mirror 1101 as light rays LOa13, LOb13, and LOc13. The light rays LOa13, LOb13, and LOc13 transmitted through the half mirror 1101 are light rays LOa14, LOb14, and LOc14. The light rays LOa14, LOb14, and LOc14 converge at a position P1 that is symmetrical to the light source O1 with respect to a surface S3 located at the center of the half mirror 1101. Therefore, the light source O1 is formed as a real image at the position P1.

[0058] Similarly, light source O2, which is farther away from surface S3 than light source O1, forms an image at position P2. As shown in Fig. 11A, the observer sees the image at position P2 in front of the image at position P1. Therefore, if a three-dimensional subject is placed instead of light sources O1 and O2, a real image with the convex-concave relationship of the subject reversed is formed in the air at a position symmetrical to surface S3.

[0059] As described above, the optical system 1100 functions as a spatial imaging element 102 that images a subject input from one surface side of the surface S3 into a real image in the air on the other surface side with the concave-convex relationship inverted.

[0060] The relationship between the incident light and the outgoing light that contribute to the image formation is that the magnitude of the incident angle and the outgoing angle with respect to the normal line of the surface S3 are the same, but the signs are opposite. Therefore, if the screen 103 and the optical system 1100 are arranged as shown in Fig. 11B, the screen 103 forms a real image at a position symmetrical to the surface S3. The observer can view the formed aerial image 104 from the direction of the arrow 105.

[0061] The spatial imaging element 102 is not limited to the above examples, and any imaging means can be used as long as it can define a plane and image a subject on one side of the plane as a real image in the air on the other side with the concave-convex relationship inverted.

[0062] Next, in order to clarify the features of the present invention, a problem that occurs when a conventional three-dimensional display is simply combined with a conventional spatial imaging element will be described.

[0063] First, a conventional three-dimensional display 1201 will be described with reference to FIGS.

[0064] FIG. 12 is a diagram for explaining an optical model of a conventional parallax barrier type three-dimensional display 1201.

[0065] Viewpoint pixels 1222 in which pixels of a viewpoint image from the right eye are displayed and viewpoint pixels 1221 in which pixels of a viewpoint image from the left eye are displayed are arranged alternately.

[0066] A parallax barrier 1230 having slits 1231 arranged at regular intervals is disposed at a position a distance h from the pixel unit 1220. The slits 1231 are disposed such that one slit 1231 corresponds to one pixel unit 1220.

[0067] Here, the light rays in the three-dimensional display 1201 are defined as follows: a light ray emitted from the left end of the viewpoint pixel 1222 in the pixel unit 1220 at the left end of the display panel 1210 and passing through the center of the shortest slit 1231 is defined as LLr1, a light ray emitted from the right end of the viewpoint pixel 1221 and passing through the center of the shortest slit 1231 is defined as LLl1, and a light ray emitted from the center of the pixel unit 1220 and passing through the center of the shortest slit 1231 is defined as LLc1. Similarly, the light rays emitted from the pixel unit 1220 at the center of the display panel 1210 are defined as LCr1, LCl1, and LCc1, and the light rays emitted from the pixel unit 1220 at the right end of the display panel 1210 are defined as LRr1, LRc1, and LRl1. When light rays LLr1, LLl1, LLc1, LCr1, LCl1, LCc1, LRr1, LRl1, and LRc1 pass through slit 1231, they are refracted due to the difference between the refractive index n inside 3D display 1201 and the refractive index of air. The refracted light rays are designated as LLr2, LLl2, LLc2, LCr2, LCl2, LCc2, LRR2, LRl2, and LRc2.

[0068] 12, a three-dimensional display 1201 is usually designed so that light rays LLc2 and LRc2 intersect at a distance OD. An area 1260L surrounded by light rays LLl2, LLc2, LCl2, LRl2, and LRc2 is an area where only the viewpoint pixel 1221 is visible, and an area 1260R surrounded by light rays LLr2, LLc2, LCr2, LRr2, and LRc2 is an area where only the viewpoint pixel 1222 is visible. Hereinafter, these areas 1260L and 1260R are referred to as single viewpoint image viewing areas.

[0069] In a conventional three-dimensional display 1201, if the viewpoint image of the left eye viewpoint is displayed at viewpoint pixel 1221, the viewpoint image of the right eye viewpoint is displayed at viewpoint pixel 1222, and the left eye 1250 is positioned within region 1260L and the right eye 1251 is positioned within region 1260R, the observer can view a stereoscopic image. The position of distance OD is the position where the observer can move the greatest in a direction parallel to the panel surface while viewing the desired stereoscopic image, that is, the optimal viewing position. For this reason, distance OD is called the optimal viewing distance.

[0070] 13 is a diagram illustrating the screen of a conventional parallax barrier type three-dimensional display 1201 seen by an observer. A screen 1300 shows the screen seen by the observer's left eye 1250. On the other hand, a screen 1301 shows the screen seen by the observer's right eye 1251.

[0071] When both eyes are inside the single-view image viewing zones 1260L, 1260R, the right eye 1251 can see the screen 1301 in FIG. 13, and the left eye 1250 can see the screen 1300 in FIG.

[0072] Next, an optical model and a screen when the observer's eyes are not in the single-viewpoint image viewing zones 1260L and 1260R will be described with reference to Fig. 14 and Fig. 15. Fig. 14 is a diagram showing an optical model of a conventional parallax barrier type three-dimensional display 1201. Fig. 15 is a diagram explaining the screen of the conventional parallax barrier type three-dimensional display 1201 seen by the observer.

[0073] As shown in Fig. 14, the observer is in a state of approaching a three-dimensional display 1201. In this case, screens 1300 and 1301 as shown in Fig. 15 are seen by the observer's left eye 1250 and right eye 1251.

[0074] The screen 1300 seen by the left eye 1250 will be described with reference to FIG.

[0075] The left eye 1250 is located between the light beam LLc2 and the light beam LLr2. Therefore, near the left edge of the screen 1300, the display of the viewpoint pixel 1222, that is, the viewpoint image of the right eye viewpoint, is seen.

[0076] 14. In addition, the left eye 1250 is located between the light beam LCl2 and the light beam LCc2. Therefore, the display of the viewpoint pixel 1221, i.e., the viewpoint image of the left eye viewpoint, is seen near the center of the screen 1300. In addition, the left eye 1250 is not located between the light beam LRl2 and the light beam LRr2. In other words, the rightmost pixel unit 1220 cannot be seen through the rightmost slit 1231 from the position of the left eye 1250 shown in FIG.

[0077] However, the left eye 1250 is located between the light beam LRr2' and the light beam LRc2'. The light beams LRr2' and LRc2' are the light beams LRr1' and LRc1' emitted from the rightmost pixel unit 1220 that have passed through the second slit 1231 from the right end. In other words, from the position of the left eye 1250, the display of the viewpoint pixel 1222, i.e., the viewpoint image of the right eye viewpoint, is seen through the second slit 1231 from the right end. Therefore, near the right end of the screen 1300, the display of the viewpoint pixel 1222, i.e., the viewpoint image of the right eye viewpoint, is seen.

[0078] As for a screen 1301 (FIG. 15) seen by the right eye 1251 located in FIG. 14, the left-right relationship is reversed with respect to the left eye 1250, so a description thereof will be omitted.

[0079] As shown in Fig. 15, when the observer's eyes are in the positions shown in Fig. 14, the observer can see a desired stereoscopic image in the center of the screen, but sees a so-called reversed image with a reversed depth relationship at the edges of the screen. As described above, when the observer's eyes are outside the single-viewpoint image viewing zones 1260L and 1260R, the observer cannot see the desired stereoscopic image.

[0080] Next, a problem that occurs when the conventional three-dimensional display 1201 and the conventional spatial imaging element 1202 are combined will be described.

[0081] Fig. 16 and Fig. 17 are diagrams for explaining an optical model of an image display device that combines a conventional three-dimensional display 1201 and a conventional spatial imaging element 1202. Fig. 18 is a diagram for explaining a screen of an image display device that combines a conventional three-dimensional display 1201 and a conventional spatial imaging element 1202, as viewed by an observer.

[0082] 12, light rays LLr1, LLc1, and LLl1 emitted from pixel unit 1220 at the left end of display panel 1210 are refracted when passing through slit 1231, becoming light rays LLr2, LLc2, and LLl2, which are incident on spatial imaging element 1202. As described above, due to the relationship between the incident light rays and the outgoing light rays to spatial imaging element 1202 that contribute to image formation, the outgoing angles of light rays LLr2, LLc2, and LLl2 are the same magnitude as the incident angle but have the opposite sign, so light rays LLr2, LLc2, and LLl2 are emitted as light rays LLr3, LLc3, and LLl3. Light rays LCr1, LCc1, and LCl1 emitted from pixel unit 1220 at the center of display panel 1210 are refracted when they pass through slit 1231, enter spatial imaging element 1202 as light rays LCr2, LCc2, and LCl2, and are emitted from spatial imaging element 1202 as light rays LCr3, LCc3, and LCl3. Light rays LRr1, LRc1, and LRl1 emitted from pixel unit 1220 at the right end of display panel 1210 are refracted when they pass through slit 1231, enter spatial imaging element 1202 as light rays LRr2, LRc2, and LRl2, and are emitted from spatial imaging element 1202 as light rays LRr3, LRc3, and LRl3.

[0083] In this way, the light emitted from the screen of the three-dimensional display 1201 forms an image at a position symmetrical with respect to the surface S of the spatial imaging element 1202, forming an aerial image.

[0084] Light rays LLc3 and LRc3 traveling from both ends of the aerial image toward the observer do not intersect on the observer side of the surface S, as shown in Fig. 16. In other words, when a conventional three-dimensional display 1201 and a conventional spatial imaging element 1202 are simply combined, single-viewpoint image viewing zones 1260L and 1260R as shown in Fig. 12 are not formed. Therefore, even if the observer positions both eyes at a distance OD from the aerial image, the desired stereoscopic image cannot be viewed.

[0085] 16, the left eye 1250 and the right eye 1251 of the observer are not located between the light beam LLl3 and the light beam LLr3. Similarly, the left eye 1250 and the right eye 1251 of the observer are not located between the light beam LRl3 and the light beam LRr3. In other words, the observer cannot see the pixel units 1220 on both ends through the slits 1231 on both ends of the 3D display 1201.

[0086] In fact, the light rays entering the observer's eye are not the light rays emitted from the edge pixel unit 1220 closest to the edge slit 1231, but from the inner pixel unit. An example is shown in FIG.

[0087] The light rays that emerge from the second pixel unit 1220 from the left end and pass through the leftmost slit 1231 are designated as LLr1', LLc1', and LLl1', and the light rays that pass through the slit 1231 and are refracted are designated as LLr2', LLc2', and LLl2'. The light rays LLr2', LLc2', and LLl2' are incident on the spatial imaging element 1202 and are emitted as light rays LLr3', LLc3', and LLl3' with an emission angle that is the same magnitude as the incidence angle but opposite in sign.

[0088] 17, the left eye 1250 is located between the light beam LLl3' and the light beam LLc3'. That is, the viewpoint image formed in the air after emitting from the left-end slit 1231 seen from the left eye position is the viewpoint image of the left eye viewpoint formed by the viewpoint pixel 1221. On the other hand, the viewpoint image formed in the air after emitting from the central slit 1231 seen from the left eye position is the viewpoint image of the right eye viewpoint formed by the viewpoint pixel 1222.

[0089] In this way, when a conventional three-dimensional display 1201 and a conventional spatial imaging element 1202 are simply combined, images in which viewpoint images from the left eye and the right eye viewpoints appear alternately on screens 1300 and 1301 are input to each of the observer's left eye 1250 and right eye 1251, as shown in Fig. 18. Therefore, the observer cannot visually recognize the desired stereoscopic image.

[0090] To solve the above problems, a three-dimensional display is required in which light rays traveling from the aerial image to the observer form single-viewpoint image viewing zones 1260L and 1260R, taking into consideration the change in light directivity that contributes to image formation by the spatial imaging element as described above. The three-dimensional display 101 of the present disclosure is designed so that, in order to form the single-viewpoint image viewing zones 1260L and 1260R, light rays that leave the centers of the pixel units 120 on both ends of the screen and pass through the slits 131 on both ends have their directivity changed by the spatial imaging element 102, and then intersect at a distance OD from the aerial image 104.

[0091] The following describes the characteristics of image display device 100 in which light rays traveling from aerial image 104 of three-dimensional display 101 formed by spatial imaging element 102 to the observer form single-viewpoint image viewing zones 1260L and 1260R.

[0092] 19 and 20 are diagrams illustrating an example of an optical model of the image display device 100 of the present disclosure.

[0093] FIG. 19 is an optical model of light rays reaching a viewer from the AA' cross section in the configuration of image display device 100 in FIG. 1, and is a projection onto the XZ plane.

[0094] The left eye 1250 and the right eye 1251 are the eyes of the observer. The aerial image 104 represents the screen of the three-dimensional display 101 formed by the spatial imaging element 102. The virtual plane 1910 represents a position where the stereoscopic image can be viewed in a suitable state. The virtual plane 1910 is a plane parallel to a line connecting both eyes, and is set at a position where the light emitted from each pixel unit 120 overlaps most. In the following description, the arrangement pattern of the slits 131 is assumed to be the arrangement pattern shown in FIG. 3. First, each parameter will be described.

[0095] The pitch width P represents the pitch width of the viewpoint pixels 121 and 122. When the pixel unit 120 is composed of two viewpoint pixels 121 and 122 as described above, the pitch width of the pixel unit 120 is 2P. The pitch width Sp represents the interval between the slits 131. The distance h represents the distance between the viewpoint pixel 121 or the viewpoint pixel 122 and the parallax barrier 130. The width WP represents the distance from the center of the pixel unit 120 arranged at the center of the display panel 110 to the center of the pixel unit 120 arranged at the edge of the display panel 110. The width WS represents the distance from the slit 131 at the center of the parallax barrier 130 to the slit 131 at the edge. The distance OD represents the distance from the aerial image 104 to the virtual plane 1910. In other words, the distance OD is the optimal viewing distance from the aerial image 104. The width e represents the enlarged projection width of the viewpoint pixels 121 and the viewpoint pixels 122 of the pitch width P on the virtual plane 1910. In other words, the width e represents an enlarged projection width that is half the pitch of the pixel units 120 on the virtual plane 1910.

[0096] In addition, the number of pixel units 120 from the center to the edge in the X direction of the display panel is denoted by m, and the refractive index inside the three-dimensional display 101 is denoted by n.

[0097] The angle α represents the maximum angle of incidence of light incident on the slit 131 located at the shortest distance from the pixel unit 120 disposed at the center of the display panel 110. In other words, the angle of incidence of the light beam LCr1 and the light beam LCl1 shown in FIG. 19 on the slit 131 is angle α.

[0098] Angle β represents the emission angle of the light ray incident on slit 131 at angle α. As described above, the normal vector of the display surface of display panel 110 projected onto the XZ plane overlaps with the normal vector of surface S of spatial imaging element 102 projected onto the XZ plane, and therefore the angle of incidence of light ray LCr2 and light ray LCl2 on spatial imaging element 102 is angle β.

[0099] The angle γ represents the angle of incidence of light incident from the center of the pixel unit 120 arranged at the end of the display panel 110 to the slit 131 arranged at the end of the parallax barrier 130. In other words, the angle of incidence of the light ray LLc1 and the light ray LRc1 shown in FIG. 19 to the slit 131 is angle γ.

[0100] Angle δ represents the exit angle of light incident on slit 131 at angle γ, and the angle of incidence of light ray LLc2 and light ray LRc2 on spatial imaging element 102 is angle δ.

[0101] 19, the three-dimensional display 101 is designed so that single-viewpoint image viewing zones 1260L and 1260R are formed by the rays of light directed toward the observer from the aerial image 104. Specifically, the parameters are determined as follows so that the rays LLc3 and LRc3 leaving the spatial imaging element 102 intersect at a distance OD.

[0102] 19, assuming that the angles of the light rays LLc3 and LRc3 are θL and θR, the magnitudes of θL and θR are equal due to geometric symmetry, and furthermore, the magnitudes of θL and θR become an angle δ due to the characteristics of the spatial imaging element 102 described above. Therefore, formula (1) is established under the condition that the light rays LLc3 and LRc3 intersect at a distance OD.

[0103]

number

[0104] The width WS in equation (1) is given by equation (2) using the pitch width Sp and the number of pixels m.

[0105]

number

[0106] Regarding the angle δ in formula (1), formula (3) holds based on the refractive index n in the three-dimensional display 101 and Snell's law.

[0107]

number

[0108] Regarding the angle γ, equation (4) holds from the geometric relationship of the distance h between the parallax barrier 130 and the pixel unit 120, the width WS, and the width WP shown in FIG.

[0109]

number

[0110] The width WP in equation (4) is calculated from the number of viewpoints, the pitch width P of the viewpoint pixels, and the number of pixels m by the equation ( 5) holds. Note that the coefficient “2” in equation (5) is the number of viewpoints.

[0111]

number

[0112] From equations (1) to (5), the pitch width 2P of the pixel unit 120 and the pitch width Sp The relationship is determined by the distance OD, the distance h, the refractive index n, and the number of pixels m. For the sake of convenience in explaining the relationship, let us assume that the approximation of equation (6) holds. By rearranging equation (5), we can derive equation (7).

[0113]

number

[0114]

number

[0115] As shown in the example of equation (7), the distance OD, the distance h, and the refraction are calculated using equations (1) to (5). If the pitch 2P of the pixel unit 120 is determined in addition to the ratio n and the number of pixels m, the light ray LLc3 and The pitch width Sp of the 3D display 101 where the light ray LRc3 intersects with the distance OD can be calculated. Note that the approximation in equation (7) no longer holds if the distance WP becomes large relative to the distance OD. Even in this case, the analytical method can be used from equations (1) to (5) and the parameters defined above. Then, the pitch width Sp at which the light beam LLc3 and the light beam LRc3 intersect at the distance OD can be calculated.

[0116] However, simply satisfying the conditions of (1) to (5) does not guarantee a single-viewpoint image viewing area 126 The projection width e of the viewpoint pixel that determines the width of 0L and 1260R cannot be set to the desired value. .

[0117] One of the conditions for the observer to view a stereoscopic image is that the left eye 1250 is within the left eye region 1260L. The right eye 1251 is located within the right eye region 1260R. Since this condition is fixed, if the width e is narrower than half the interocular distance, this condition cannot be met. That is, the observer cannot visually recognize a stereoscopic image.

[0118] In general, the average interocular distance for adult men is 65 mm, with a standard deviation of ±3.7 mm. The mean interocular distance for Japanese women is 62 mm, with a standard deviation of ±3.6 mm (Neil A Dodgson, “Variation and extrema of human interpupillary distance”, Proc.SPIE vol.5 291). From this, if the observer's interocular distance is 65 mm, the width e must be at least 32.5 At least mm is required.

[0119] In addition, a state in which both eyes are located within a predetermined single viewpoint image viewing area, i.e., a stereoscopic image can be visually recognized In this state, the range in which the observer can move in the direction parallel to the aerial image 104 (X direction) is considered to be large. Considering this, it is preferable that the width e is set to 65 mm or more.

[0120] The width e is the enlarged projection width of the viewpoint pixel of the pitch width P, the pitch width P, the distance OD, the distance h, Depending on the refractive index n, the following relationship holds:

[0121] In the case of the ray LCl3 in Figure 19, the width e is the tangent of the distance OD. The magnitude of the degree θc becomes the angle β due to the characteristics of the spatial imaging element 102 described above. , equation (8) holds.

[0122]

number

[0123] The angle β in equation (8) is determined by the internal refractive index n of the 3D display 101 and the Snell's law From the rule, equation (9) is satisfied.

[0124]

number

[0125] The angle α in formula (9) satisfies formula (10) based on the geometric relationship between the pitch width P and the distance h. vinegar.

[0126]

number

[0127] Therefore, using equations (8) to (10), the pitch width P, the distance OD, the distance h, and By determining the refractive index n, the width e can be set to a desired value, and each parameter for which the width e is set The pitch width Sp can be calculated by using the values ​​of the parameters in equations (1) to (5).

[0128] In this disclosure, the pitch width Sp of the three-dimensional display 101 is calculated by the following formulas (1) to (5), and the value is calculated using equations (8) to (10).

[0129] In addition, when N viewpoint pixels are included in the X direction of the pixel unit 120, the formula (5 Instead of the width WP defined by equation (11), the width WP defined by equation (11) may be used.

[0130]

number

[0131] In addition, the width e is set by half the pitch (N·P) of the pixel unit 120 and the distance h. In other words, equation (12) can be used instead of equation (10). stomach.

[0132]

number

[0133] The combination of the three-dimensional display 101 and the spatial imaging element 102 designed as above As a result, as shown in FIG. 19, the light rays traveling from the aerial image 104 to the observer are reflected in the single-viewpoint image viewing area 12. 60L, forming 1260R.

[0134] Therefore, the left and right viewpoint images are displayed at viewpoint pixels 121 and 122, respectively, and the left eye 1250 is When the right eye 1251 is positioned within the right eye region 1260R, the viewer The viewer can view a suitable stereoscopic image across the entire screen.

[0135] It should be noted that the observer views the three-dimensional display 101 shown in FIG. When viewed directly, the observer cannot see the desired stereoscopic image. As shown in FIG. Since the light rays LLc2 and LRc2 that pass through the slits 131 at both ends do not intersect, This is because a single-viewpoint viewing zone is not formed. In this case, the light rays toward the observer are as shown in FIG. The optical model is the same as that of Fig. 17, and the screen seen by the observer is the same as that of Fig. 18. The viewer sees an image in which normal viewing areas and reverse viewing areas appear alternately on the screen.

[0136] The single-viewpoint image viewing area 1260L is made up of rays LLl3, LLc3, LCl3, LRl3, and LRc 3, and the single-viewpoint image viewing area 1260R is LRr3, LLr3, LLc3 , LRc3, and LCr3. Therefore, the spatial imaging element 102 of the present disclosure must be wide enough in the X direction to allow at least these rays to pass through.

[0137] The width required for the spatial imaging element 102 will be described with reference to FIG.

[0138] The distance from the center to the edge of the spatial imaging element 102 is WI. The distance from the Lux barrier 130 to the surface S of the spatial imaging element 102 is Dpi, and the light ray L The incident angle of the light beam Lr1 and the light beam LLl1 to the slit 131 is the angle ε, and the light beam LLr2 and the light beam L The exit angle of Ll2 from the slit 131 is defined as angle ζ. Reference numeral 102 denotes an end portion having a width allowing the light beams LLr3 and LRl3 to exit.

[0139] In this case, equation (13) holds.

[0140]

number

[0141] In addition, the angles ζ and ε are determined by the refractive index n and Snell's Equation (14) holds true from this law.

[0142]

number

[0143] In addition, the angle ε in formula (14) is expressed by the following equation: Equation (15) holds due to the geometric relationship.

[0144]

number

[0145] From equations (14) and (15), the angle ζ is expressed as equation (16), and the angle ε is expressed as equation (1 7) can be expressed as follows.

[0146]

number

[0147]

number

[0148] By rearranging equation (13) using equations (15) to (17), the distance WI is given by equation (18). It can be expressed as follows.

[0149]

number

[0150] That is, the width WI is calculated from the width WS, the width WP, the pitch width P, the distance h, and the distance Dpi. The width WS can be calculated from formula (2), and the width WP can be calculated from formula (5).

[0151] As described above, in the image display device 100 of the present disclosure, The spatial imaging elements required to form single-viewpoint image viewing areas 1260L and 1260R using these light rays are The width WI of the child 102 must satisfy the formula (19).

[0152]

number

[0153] In addition, when N viewpoint pixels are included in the X direction of the pixel unit 120, the formula (5 Instead of the width WP defined by equation (20), the width WP defined by equation (20) may be used.

[0154]

number

[0155] In this case, the width WI must satisfy the formula (21).

[0156]

number

[0157] Here, referring to FIG. 21 and FIG. 22, the problem with the image display device disclosed in Patent Document 4 will be described. This article explains:

[0158] 21A and 21B are diagrams illustrating an optical model of the image display device described in Patent Document 4. FIG. 21A shows an ideal optical model of the image display device disclosed in Patent Document 4. FIG. 21B shows an actual optical model of the image display device disclosed in Patent Document 4. A case where a pixel providing a plurality of viewpoint groups provides two viewpoints will be described.

[0159] Patent Document 4 discloses a display device including a 3D display module 2101 and an optical element 2102. An image display device 2100 is disclosed. The 3D display module 2101 has a backlight. The pixel 2120 includes a light source 2140, a plurality of pixels 2120, and a parallax barrier 2130. 2120 includes a plurality of viewpoint groups. Here, there are two viewpoint groups 2121 and 2122. This is to be included.

[0160] In Patent Document 4, the pitch width of the pixel 2120 is defined as Pv, and the parallax barrier 213 The pitch width of the aperture 2131 of the pixel 210 is defined as Pb1. The distance between the backlight source 2140 and the object 20 is defined as d1. The light is focused at a virtual focus Fv, and the backlight source 2140 is coupled to the virtual focus Fv and the optical element 2102. The distance between the virtual focus Fv and the parallax barrier 2130 is is defined as the distance VD from the observer 2180 to the virtual floating base surface 2150 (the aerial image of the present disclosure). 104) is equal to the distance from the virtual focus Fv to the parallax barrier 2130. In other words, the virtual floating base surface 2150 and the observation position of the observer 2180 The distance between the virtual plane 2160 and the point VD is defined as VD.

[0161] In Patent Document 4, the ratio of the pitch width Pb1 to the pitch width Pv is VD / (VD-d1). Therefore, the opening 2131 of the parallax barrier 2130 The pitch width Pb1 can be calculated by equation (22) once VD, Pv, and d1 are determined.

[0162]

number

[0163] The optical model shown in FIG. 21A and equation (22) of Patent Document 4 are the three-dimensional Refractive index within the 3D display module 2101 corresponding to the display 101 This holds true when n is 1.

[0164] However, in reality, the refractive index n inside the 3D display module 2101 is set to the refractive index of air. Therefore, the opening 213 as shown in FIG. 21A cannot be the same as the opening 213 as shown in FIG. The light rays LB and LR passing through 1 do not form straight lines, but are refracted, as shown in Figure 21B. It becomes an optical model.

[0165] As shown in FIG. 21B, when refraction is taken into consideration, the condensed light of the backlight source 2140 is The point is located at a position shorter than the distance VD, and the observer 2180 can view a suitable stereoscopic image. In order to observe the image display device 2100, the viewer must be closer than the distance VD. You can see that.

[0166] Next, regarding the design problems derived from the disclosure of Patent Document 4, we will consider specific values ​​for Equation (22). Set up and consider the following.

[0167] The first problem is that VD (OD in this disclosure), d1 (h in this disclosure), and Pv (The width of the pixel unit in this disclosure, 2 P) corresponds to the magnified projection width e of the viewpoint pixel. The corresponding design requirements are not clearly stated in Patent Document 4. Therefore, the setting of VD, d1, and Pv Depending on the setting, the width e may be narrower than half the interocular distance (32.5 mm).

[0168] For example, consider d1 and width e when VD is 500 mm and Pv is 0.2 mm. In the above formulas (8) to (10), n=1, OD=VD, and P=Pv / 2. If d1 is not smaller than 1.54 mm, the width e is smaller than 32.5 mm. In other words, if VD is set to 500 mm and P With v set to 0.2 mm and d1 set to 1.54 mm or more, the pitch width Pb1 is calculated from equation (22). If the calculated image display device is designed, the observer will not be able to see the stereoscopic image at the position of distance VD. .

[0169] The second problem is that the internal bending of the 3D display module 2101 in Patent Document 4 is The refractive index is not taken into account. Therefore, the intersection points of the light rays from both sides of the screen are not taken into account. Here, VD is 500 mm, Pv is 0.2 mm, n=1, and width e is 65 m. When d1, which becomes m, is calculated from the formulas (8) to (10) of the present disclosure as described above, d1 VD is 500 mm, Pv is 0.2 mm, and d1 is 0.77 mm. In this case, Pb1 is calculated as 0.200308 mm using formula (22). Summarize the design values ​​of v, d1, and Pb1.

[0170] [Table 1]

[0171] When the 3D display module 2101 is designed as shown in Table 1, The effect of the refractive index on the light rays LLc3 and LRc3 shown in the optical model in Figure 19 As defined in FIG. 19, the light ray L Let OD be the distance to the intersection of Lc3 and ray LRc3.

[0172] FIG. 22 is a graph showing the relationship between the refractive index n and the number of pixels m and the distance OD. Table 1 shows the relationships in the design.

[0173] As shown in FIG. 22, the refractive index n inside the 3D display module 2101 is If the distance OD is the same as that of the light (n=1), it will be 500 mm regardless of m. However, refraction As the refractive index n becomes larger than 1, the distance OD becomes smaller. In other words, when m is large, the distance OD becomes smaller as m becomes larger. Due to the prime number m, the observer must be closer to the aerial image than the designed VD=500mm position. If the distance is not large, it is not possible to observe a stereoscopic image satisfactorily.

[0174] Next, in the design of Table 1, the number of pixels m is set to 500, and the light rays for n = 1 and n = 1.5 Let us create a diagram and consider the single-viewpoint image viewing zones 1260L and 1260R. 3B and 23C are illuminating diagrams illustrating the single viewpoint image viewing area of ​​an image display device in any design. This is a diagram.

[0175] FIG. 23A shows the results of the experiment with m=500 and n=1, and the other values ​​are the design values ​​in Table 1. This is a diagram showing the rays shown in FIG.

[0176] The vertical axis represents the Z-axis direction, in mm, with 0 being the position of the aerial image, and -100 mm being the position. The optical element 2102 (surface S of the spatial imaging element 102 of the present disclosure) is disposed. The horizontal axis is the X direction. The unit is mm, with 0 being the center of the 3D display module 2101.

[0177] In FIG. 23A, the light rays LLc3 and LRc3 intersect at Z=500 mm. The lines form single-viewpoint image viewing zones 1260L and 1260R. Thus, the observer As designed, the stereoscopic image can be seen at a distance of 500 mm from the aerial image.

[0178] FIG. 23B shows the results when m=500, n=1.5, and other values ​​are the design values ​​shown in Table 1. 9 is a calculated drawing of each ray shown in FIG.

[0179] In this case, the intersection point of the light rays LLc3 and LRc3 is Z = 324.87 mm. As shown in 23B, it is surrounded by rays LLl3, LLc3, LCl3, LRl3, and LRc3. A single viewpoint image viewing area 1260L and light rays LLr3, LLc3, LCr3, LRr3, L The single-viewpoint image viewing area 1260R surrounded by Rc3 is a space closer than Z=500mm (aerial image side ) is formed.

[0180] Therefore, the observer can easily view the stereoscopic image at a distance of 500 mm from the aerial image. Since both eyes are not positioned in the single-viewpoint image viewing areas 1260L and 1260R, As explained in 5, the desired stereoscopic image cannot be seen at the edge of the screen. In order for the observer to see the desired stereoscopic image, the observer must be closer than the design value, i.e., VD = 500 mm. , preferably to a position of 324.87 mm.

[0181] The design of the 3D display module 2101 according to Patent Document 4 shown in Table 1 and the present disclosure Compare the designs of the three-dimensional display 101 (FIG. 19) of the two.

[0182] The distance VD is the distance OD in this disclosure, and the distance OD is set to 500 mm. The pitch width Pv=0.2 mm in Patent Document 4 is adjusted to the pitch width P in this disclosure to be 0.1 mm. If n=1.5 and the magnified projection width e is 65 mm, equations (8) to (10) Therefore, the distance h corresponding to d1 is calculated to be 1.16 mm. Add m = 500 to these values ​​and Then, the pitch width Sp of the parallax barrier 130 is calculated using equations (1) to (5). , 0.200306 mm. Table 2 summarizes these design values.

[0183] [Table 2]

[0184] FIG. 23C shows the light rays shown in FIG. 19, calculated using the design values ​​in Table 2. FIG.

[0185] As shown in FIG. 23C, the light beams LLc3 and LRc3 intersect at Z=500 mm, The light rays form single-viewpoint image viewing zones 1260L and 1260R. As designed, the desired stereoscopic image can be seen at a distance of 500 mm from the aerial image. It can be seen that by using the disclosed calculation formula, it is possible to provide the image display device 100 as designed. .

[0186] According to the first embodiment, it is possible to design an image display device 100 that allows a suitable three-dimensional image to be viewed. It is possible.

[0187] In the present invention, the extension direction of the slit 131 shown in FIG. 3 corresponds to the arrangement direction of the viewpoint pixels. Instead of a 3D display using a parallax barrier 130 parallel to the Y-axis direction, A three-dimensional display as shown in FIG. 31 is also possible.

[0188] FIG. 31 shows the slit 131 of the parallax barrier 130 functioning as a distribution unit. The extension direction is an angle λ with respect to the direction of the viewpoint pixel arrangement (Y-axis direction). As shown in Figure 31, the slits are arranged at an angle to the array of viewpoint pixels. By doing so, not only can the light rays from the viewpoint pixels arranged in the X direction be distributed as shown in Fig. 3, but also the Y The light rays of the viewpoint pixels aligned in the direction can also be distributed in different directions. In other words, the pixel unit is , the configuration includes not only viewpoint pixels in the X direction but also viewpoint pixels in the Y direction. The viewpoint image can be presented in the direction of the viewpoint pixel 125. The number shown in each viewpoint pixel 125 is the number of the viewpoint image to be formed. It is.

[0189] When a three-dimensional display such as that shown in FIG. 31 is applied to the present invention, the slip in the X direction The pitch of the viewpoint pixel 125 is Sp, the pitch of the viewpoint pixel 125 is P, and the allocation unit in the X direction corresponds to The number of viewpoints is N (N=3 in the case of Figure 31), and the number of pixel units from the center to the edge in the X direction is Let m be the number, and substitute it into equations (2), (11), and (12). As explained above, As described above, the allocation unit is arranged diagonally with respect to the viewpoint pixel. In this case, the number of viewpoints N in the X direction of the pixel unit is not limited to an integer.

[0190] [Second embodiment] In the second embodiment, the configuration of the three-dimensional display 101 is different. 1 is a diagram showing an outline of an optical model of the image display device 100. FIG. FIG. 24 is a diagram showing a structure and an optical model. FIG. 24 corresponds to FIG. 2 described in the first embodiment. do.

[0191] The three-dimensional display 101 of the second embodiment uses a lenticular lens as an optical separation means. The three-dimensional display 101 is a three-dimensional display that uses a display panel. The lens 110 and the lenticular lens 140.

[0192] The lenticular lens 140 has cylindrical lenses 141 arranged in a certain pattern. FIG. 25 shows a lenticular lens in the center of the three-dimensional display 101 of the present disclosure. 1 is a schematic diagram (XY plan view) of lens 140.

[0193] The focal length of the cylindrical lens 141 is the distance from the apex of the cylindrical lens 141 to the center of the The refractive index and the radius of curvature are designed so that the distance to the point pixel is approximately equal to the distance h. For convenience, the refractive index of the cylindrical lens 141 and the refractive index inside the three-dimensional display 101 are shall be considered equal.

[0194] Since the focal length of the cylindrical lens 141 is approximately equal to the distance h, The light emitted isotropically from 122 becomes almost parallel after passing through the cylindrical lens 141. For this reason, a lenticular lens 140 is suitably disposed on the display panel 110. By this, specific viewpoint pixels 121 and 122 (viewpoints) are projected through the cylindrical lens 141. In other words, the lenticular lens 140 is a region in which only the display panel (a group of pixels) is visible. An optical system that distributes the light rays emitted from the image displayed on the display unit 110 into light rays for each viewpoint image. The cylindrical lens 141 functions as a separation unit (distribution unit). The cylindrical lens 141 is arranged so that one pixel unit 120 corresponds to the other pixel unit 120. will be done.

[0195] The lenticular lens 140 is electrically switched on and off. In this case, you can turn off the lens to eliminate the stereoscopic effect. It can provide not only a single image but also a planar image.

[0196] As described above, the lenticular lens 140 in this embodiment has the same structure as that in the first embodiment. Since it functions as an optical separation means similar to the parallax barrier 130 in Detailed explanation will be omitted.

[0197] In this embodiment, the display panel 110 displays an image including two viewpoint images. As an example, a display panel 110 that displays an image including three or more viewpoint images will be described. In this case, the pixel unit 120 may display pixels of each of the multiple viewpoints. It is constructed from prime groups.

[0198] FIG. 26 is a diagram illustrating an example of an optical model of the image display device 100 of the present disclosure.

[0199] The optical model of the image display device 100 shown in FIG. 26 is the same as that of the image display device 100 shown in FIG. The parallax barrier 130 is connected to a lenticular lens 140, and the slit 131 is connected to a cylindrical lens. This is an optical model in which the lens is replaced with a Cull lens 141.

[0200] The pitch width Sp representing the interval between the slits 131 in FIG. 19 and the corresponding cylindrical lens 1 The interval between the slits 41 is the pitch width Lp, and the slit 131 at the center of the parallax barrier 130 in FIG. The distance WS from the edge slit 131 to the center of the corresponding lenticular lens 140 is The distance from the cylindrical lens 141 to the end cylindrical lens 141 is called the pitch width W The distance h is the distance from the apex of the cylindrical lens 141 to the viewpoint pixel 121, The distance is indicated up to 22. The other symbols and configurations are the same as those in FIG.

[0201] The three-dimensional display 101 in the second embodiment is also a single In order to form the viewpoint image viewing areas 1260L and 1260R, The light emitted from the center passes through the cylindrical lenses 141 on both ends and enters the spatial imaging element 102. Therefore, after changing the directivity, it is designed to intersect at a distance OD from the aerial image 104. Therefore, in the X direction of the display panel 110, the pixel units 120 from the center to the edge If the number of pixels is m, similarly to the relationship between equations (1) to (5), the following equation (23) can be obtained: (27) is derived.

[0202]

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[0207] In addition, by using equations (8) to (10), the pitch width P, the distance OD, the distance h, and the bending angle By determining the ratio n, the width e can be set to a desired value. By substituting the values ​​from equation (23) to equation (26), the The pitch width Lp can be calculated.

[0208] Here, the relationship between equations (1) to (5) and equations (21) to (25) is as follows: In the above, Sp is replaced with Lp. Therefore, the image display device 10 of the second embodiment The width required for the spatial imaging element 102 at 0 is expressed by the following equation (19) or (21): In the above, the width WI can be calculated by substituting WL for WS and Lp for Sp.

[0209] In addition, when N viewpoint pixels are included in the X direction of the pixel unit 120, the formula (2 Instead of the width WP defined in (7), the width WP defined in (11) can be used. In addition, the width e is set by determining an angle based on half the pitch (N·P) of the pixel units 120 and the distance h. In other words, equation (12) should be used instead of equation (10).

[0210] The image display device 100 of the second embodiment designed as described above has the same functions as the first embodiment. Furthermore, the lenticule used in the optical separation means of the three-dimensional display 101 has the same effect. The parallax lens 140 has a higher light utilization efficiency than the parallax barrier 130. Compared with the image display device 100 of the embodiment, it is possible to provide a brighter aerial image or reduce power consumption. It becomes possible.

[0211] In the present invention, the extending direction of the cylindrical lens 141 shown in FIG. A three-dimensional display using a lenticular lens 140 parallel to the pixel arrangement direction (Y-axis direction) Instead of rays, a three-dimensional display as shown in FIG. 32 can also be applied.

[0212] FIG. 32 shows a view in which the extension direction of the cylindrical lens 141 functioning as a sorting unit is a viewing direction. This is an example of a 3D display in which the pixels are arranged at an angle λ with respect to the Y-axis direction. As shown in Figure 32, the cylindrical lens is tilted with respect to the array of viewpoint pixels. This not only distributes the light rays from the viewpoint pixels arranged in the X direction as shown in Figure 25, but also distributes them in the Y direction. The light rays of the viewpoint pixels aligned in the direction can also be distributed in different directions. In other words, the pixel unit is , the configuration includes not only viewpoint pixels in the X direction but also viewpoint pixels in the Y direction. The viewpoint image can be presented in the direction of the viewpoint pixel 125. The number shown in each viewpoint pixel 125 is the number of the viewpoint image to be formed. It is.

[0213] When a three-dimensional display as shown in FIG. 32 is applied to the present invention, the cylinder in the X direction The pitch width Lp of the local lens 141, the pitch of the viewpoint pixel 125, and the distribution in the P and X directions The number of viewpoints that the unit supports is N (N=3 in the case of Figure 32), and the number of points from the center to the edge in the X direction is Let m be the number of pixel units in and substitute it into equations (24), (11), and (12). As explained above, the pitch width Lp can be calculated. When the pixels are arranged diagonally, the number of viewpoints N in the X direction of the pixel unit is limited to an integer. I can't.

[0214] [Third embodiment] In the third embodiment, the configuration of the three-dimensional display 101 is different. In this embodiment, the parallax barrier 130 and the lenticular lens 131 function as an optical separation means. 40 was disposed on the spatial imaging element 102 side of the display panel 110. In this embodiment, the optical separation means is disposed on the opposite side of the display panel 110 from the spatial imaging element 102. It will be placed.

[0215] FIG. 27 is a diagram illustrating an example of an optical model of the image display device 100 of the present disclosure.

[0216] The image display device 100 of this embodiment has a spatial imaging element 102 for a display panel 110. A parallax barrier 130 is provided on the opposite side to the image display device 100. A projector 150 is provided on the parallax barrier 130 side of the three-dimensional display 101. Equipped with.

[0217] Hereinafter, the light rays traveling from the aerial image 104 to the observer are represented by single-viewpoint image viewing zones 1260L and 1260R. The features of the image display device 100 that forms the image display device 100 will be described. The explanation about this will be omitted.

[0218] As shown in FIG. 27, the condition that the light rays LLc3 and LRc3 intersect at the distance OD is expressed as follows: 28) holds true.

[0219]

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[0220] The width WS in formula (28) satisfies formula (29) based on the pitch width Sp and the number of pixels m. do.

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[0222] In addition, the formula (30) is established from the refractive index n inside the 3D display 101 and Snell's law. do.

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[0224] In addition, the angle γ is determined from the geometric relationship between the distance h and the widths WS and WP shown in FIG. Then, equation (31) holds.

[0225]

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[0226] The width WP is the number of viewpoints, 2, the pitch width P of the viewpoint pixels, and the number of pixel units from the center to the edge. Equation (32) holds true based on the number of pixels m.

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[0228] In addition, by using equations (8) to (10), the pitch width P, the distance OD, the distance h, and the bending angle By determining the ratio n, the width e can be set to a desired value. By substituting the values ​​from equation (28) to equation (32), the pitch width Sp of the slit 131 is obtained. can be calculated.

[0229] In addition, when N viewpoint pixels are included in the X direction of the pixel unit 120, the formula (3 Instead of the width WP defined in 2), the width WP defined in equation (11) can be used. In addition, the width e is set by determining an angle based on half the pitch (N·P) of the pixel units 120 and the distance h. In other words, equation (12) should be used instead of equation (10).

[0230] Furthermore, as described in the first embodiment with reference to FIG. 31, the parallax barrier 13 The extension direction of the slit 131 of No. 0 is arranged at an angle λ with respect to the arrangement direction of the viewpoint pixel (Y-axis direction). It is also possible to apply a structure in which the

[0231] The image display device 100 of the third embodiment designed as above has the same structure as the image display device of the first embodiment. The same effects as those of the image display device 100 are achieved.

[0232] [Fourth embodiment] In the fourth embodiment, the configuration of the three-dimensional display 101 is different. The parallax lens used as the optical separation means of the image display device 100 shown in the third embodiment Instead of the barrier 130, a lenticular lens 140 is used.

[0233] FIG. 28 is a diagram showing an example of an optical model of the image display device 100 of the present disclosure.

[0234] As in the second embodiment, a lenticular barrier is used instead of the parallax barrier 130. When the lens 140 is used, WL is substituted for WS and Lp is substituted for Sp to calculate each parameter. Therefore, by using equations (28) to (32), WS is replaced with WL and Sp with Lp. Then, the pitch width Lp of the cylindrical lenses 141 can be calculated.

[0235] Furthermore, as described in the first embodiment with reference to FIG. 32, The extension direction of 41 is arranged at an angle λ with respect to the arrangement direction of the viewpoint pixel (Y-axis direction). It is also possible to use

[0236] The image display device 100 of the fourth embodiment designed as above has the same structure as the image display device of the first embodiment. The same effects as those of the image display device 100 are achieved.

[0237] [Fifth embodiment] In the fifth embodiment, the configuration of the three-dimensional display 101 is different.

[0238] 29 and 30 are diagrams showing an outline of an optical model of the image display device 100 of the present disclosure. .

[0239] The three-dimensional display 101 includes a light projector 150, a three-dimensional print 160, and a lenticular It has a lens 140.

[0240] The three-dimensional print 160 is a print of images from multiple viewpoints. For example, multiple viewpoints are divided into strips and the strips of each viewpoint are arranged in a certain pattern. The three-dimensional printed matter 160 is not limited to the type of the three-dimensional printed matter 160. FIG. 29 shows an example in which images from two viewpoints are printed in strips on the back side of a lenticular lens 140. In order to display more multi-viewpoint images, each viewpoint image is divided into pixel units 120. The above arrangement can be adopted.

[0241] The light projector 150 is a device that projects light onto the three-dimensional printed object 160. The light projector 150 is configured, for example, of an LED element.

[0242] The light projected from the light projector 150 to the three-dimensional printed matter 160 is included in the three-dimensional printed matter 160. The light beams corresponding to the respective viewpoint images are separated by the cylindrical lens 141.

[0243] In FIG. 29, the projector 150 is disposed on the rear side of the lenticular lens 140 (the three-dimensional printed matter). 30, the projector 150 is disposed on the lenticular lens 14 side. The light emitted from the projector 150 passes through the lenticular lens 140. The light reflected by the printed viewpoint pixels is split by the cylindrical lens 141. Although not shown, a front light may be used as the projector 150.

[0244] The optical model of the image display device 100 of the fifth embodiment is the same as that of the second embodiment. Therefore, the pitch width Lp of the cylindrical lenses 141 of the three-dimensional print 160 is the second As in the embodiment, it can be calculated as follows.

[0245] Using equations (8) to (10), the pitch width P, the distance OD, the distance h, and the refractive index n are calculated as follows: By setting the width e to a desired value, the value of each parameter for which the width e is set is calculated using the formula (2 3) into equation (27), the pitch width L of the cylindrical lens 141 is obtained. p is calculated. The width required for the spatial imaging element 102 is calculated using the formula (19) or the formula In (21), by replacing WS with WL and Sp with Lp, the width WI can be calculated. do.

[0246] Therefore, the fifth embodiment has the same effects as the second embodiment.

[0247] [Sixth embodiment] The 3D display of the present invention projects a stereoscopic image, and displays different viewpoint images depending on the observation position. It is also possible to apply the present invention to a multi-display that projects images.

[0248] Below, we will discuss its application to a multi-display system that projects two different images depending on the viewing position. In the following description, the parallax barrier 130 is used to project a spatial image onto the display panel 110. The optical model shown in FIG. 19 is used, which is arranged on the element 102 side, but for a multi-display The application of the present invention is possible by using a lenticular lens 140 (optical model shown in FIG. 26) or a display A configuration in which an optical separation means is disposed on the opposite side of the panel 110 from the spatial imaging element 102. (Optical models shown in Figs. 27 and 28) or using a 3D print 160 for a 3D display. This is also possible in a configuration in which the optical axis is shifted in the opposite direction (optical models shown in Figs. 29 and 30).

[0249] As already explained, in a three-dimensional display, a single viewpoint image viewing area 1260L and a single viewpoint image viewing area 126 It is designed to form a 0R image and be visible as a 3D image when the observer's eyes are in the specified positions. In a multi-view display, the observer's left and right eyes are positioned in one single-viewpoint image viewing area. When the single viewpoint is in the viewing area, a different viewpoint image can be observed. Design the single-viewpoint image viewing area to be large. In other words, design e to be larger than the interocular distance.

[0250] In the following, a design example in which the enlarged projection width e is 300 mm in the optical model of FIG. 19 will be described. If the distance OD is 500 mm, the pitch width P is 0.1 mm, and n = 1.5, then equation (8 ) and (10), the distance h is calculated to be 0.274 mm. In addition, the pitch width Sp of the parallax barrier 130 is calculated using equations (1) to (5). The result is 0.200072 mm. Table 3 summarizes these design values.

[0251] [Table 3]

[0252] FIG. 33 is a diagram in which the rays shown in FIG. 19 are plotted by calculation using the design values ​​in Table 3. As shown in FIG. 33, the light rays LLc3 and LRc3 intersect at Z=500 mm. Each light ray forms a single-viewpoint image viewing zone 1360, 1361. 0 is an area where only the viewpoint pixel 121 shown in FIG. 19 is visible, and the single viewpoint image viewing area 1361 is , this is an area where only the viewpoint pixel 122 shown in FIG. 19 is visible.

[0253] Here, as shown in FIG. 34, a viewpoint image 1400 is displayed at viewpoint pixel 121, and When a viewpoint image 1401 is displayed on the display 22, the left and right eyes of the observer are positioned within a single viewpoint image viewing area 1360. When the camera is positioned in the viewing position, the viewer sees the viewpoint image 1400 as shown in FIG. When both eyes are located within the single-viewpoint image viewing zone 1361, the observer sees the viewpoint as shown in FIG. View statue 1401.

[0254] The image display device 100 of the present invention designed as described above displays different images depending on the viewing position. A screen consisting of a single viewpoint image can be provided as an aerial image. The width required for the imaging element 102 can be calculated from equation (19) or equation (21).

[0255] In addition, a multi-display display designed to provide an aerial image as shown in Figs. 35A and 35B is The case where the play is observed without a spatial imaging element will be described with reference to Figs. 36 and 37. do.

[0256] FIG. 36 shows the case where there is no spatial imaging element, that is, the light coming out of the slit 131 in FIG. The rays LLl2, LLc2, LLr2, LCl2, LCc2, LCr2, LRl2, LR This is a diagram of c2 and LRr2 drawn by calculation, similar to Figure 33.

[0257] As shown in FIG. 36, the light rays LLc2 and LRc2 do not intersect, and each light ray A single-viewpoint viewing area is not formed. Therefore, the screen seen by the observer contains a mixture of two viewpoints. As an example, as shown in FIG. 36, the left eye 1250 of the observer is located at X=10 mm and Z= 500 mm, and the right eye 1251 is located at X = 75 mm, Z = 500 mm, The screen you will see is shown in Figure 37.

[0258] As shown in FIG. 37, the screen projected to each eye has an area of ​​a viewpoint image 1400 and a viewpoint image 1401. The area of ​​the image 1401 is included.

[0259] Although the embodiments of the present application have been described above, the present disclosure is not limited to the above embodiments. Those skilled in the art can easily modify or add elements of the above embodiments within the scope of the present disclosure. It is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment. It is possible to change the configuration of one embodiment and add the configuration of another embodiment to the configuration of another embodiment. It is.

[0260] Representative aspects of the invention other than those described in the claims are as follows: (1) a projection device that projects a display image including a plurality of viewpoint images having different viewpoints; a spatial imaging element that projects the display image as a real image into space; A display device comprising: a distribution mechanism in which a plurality of distribution units that distribute light of the display image are arranged at regular intervals so that a viewpoint image viewing zone for each of the plurality of viewpoint images is formed; each of the plurality of allocation units is arranged so that one of the allocation units corresponds to a pixel unit constituted by a plurality of viewpoint pixels that display the plurality of viewpoint images; the distribution mechanism is disposed between the pixel unit and the spatial imaging element, The interval (Sp) of the sorting units is The number (N) of the plurality of viewpoint pixels constituting the pixel unit; and The number of pixel units (m) from the center of the projection device to the edge of the projection device; and The distance (WP) from the pixel unit at the center of the projection device to the pixel unit at the edge of the projection device; A distance (WS) from the allocation unit corresponding to the pixel unit at the center of the projection device to the allocation unit corresponding to the pixel unit at the edge of the projection device; A pitch width (P) of one viewpoint pixel included in the pixel unit; An angle (α) of light of the pixel unit at the center of the projection device irradiated to the distribution unit and an angle (β) of the light emitted from the distribution unit; An angle (γ) of light of the pixel unit at the end of the projection device irradiated to the distribution unit and an angle (δ) of the light emitted from the distribution unit; A distance (h) between the projection device and the sorting unit; The refractive index (n) of the distribution mechanism; the distance between the real image and the observer's optimum viewing position (OD); A projection width (e) of half the pitch of the pixel unit at the distance (OD) from the real image is calculated according to equations (33) to (39) defined using the distance (OD) from the real image, The display device is characterized in that the refractive index (n) is greater than 1.

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[0261] 100 Image display device 101 3D Display 102 Spatial Imaging Element 103 screens 104 Aerial image 105 Arrow 110 Display Panel 120 pixel units 121, 122, 125 Viewpoint pixels 130 Parallax Barrier 131 Slit 140 Lenticular Lens 141 Cylindrical Lens 150 Floodlight 160 3D Prints 400 Afocal Lens Array 401, 402 Lens array 411 Array 600 mirror element array 601 Unit Optical Element 700 mirror element array 701, 702 elements 710, 710 mirror surface 1000, 1010 Retroreflective sheet 1100 Optical system 1101 Half mirror 1102 Retroreflective sheet 1250 left eye 1251 Right eye 1260L, 1260R, 1360, 1361 Single viewpoint image viewing area

Claims

1. a spatial imaging element having a plane and configured to form a real image of an object on one side of the plane in the air on the other side of the plane, the real image having an inverted concave-convex relationship; a three-dimensional display including a display panel having viewpoint pixels for displaying a plurality of viewpoint images, and a distribution mechanism for distributing light of the viewpoint images of the display panel; A display device that forms a viewpoint image of the three-dimensional display in the air by the spatial imaging element, The viewpoint image projected by the three-dimensional display includes a normal viewing area and an inverse viewing area within a screen, and there is no observation position where the entire screen is a normal viewing area or a reverse viewing area, An observation position exists in which the entire screen of the image formed by the spatial imaging element in the air from the viewpoint image is a normal viewing area. A display device comprising:

2. The display device according to claim 1 , The distribution mechanism has a refractive index different from that of air, A display device, characterized in that a light ray that leaves the viewpoint pixel and passes through the distribution mechanism is refracted.

3. The display device according to claim 1 , A display device, characterized in that an area of ​​the spatial imaging element is larger than a display area of ​​the display panel.

4. a spatial imaging element having a plane and configured to form a real image of an object on one side of the plane in the air on the other side of the plane, the real image having an inverted concave-convex relationship; a multi-display including a display panel having viewpoint pixels for displaying a plurality of viewpoint images and a distribution mechanism for distributing light of the viewpoint images of the display panel; a display device that forms a viewpoint image of the multi-display in the air by the spatial imaging element, a viewpoint image projected by the multi-view display includes, within a screen, an area of ​​an arbitrary viewpoint image and an area of ​​a viewpoint image different from the arbitrary viewpoint image; The image formed in the air by the spatial imaging element from the viewpoint image has an observation position where the entire screen is an arbitrary viewpoint image. A display device comprising:

5. The display device according to claim 4, The distribution mechanism has a refractive index different from that of air, A display device, characterized in that a light ray that leaves the viewpoint pixel and passes through the distribution mechanism is refracted.

6. The display device according to claim 4, A display device, characterized in that an area of ​​the spatial imaging element is larger than a display area of ​​the display panel.

Images