JP2009063879A - Stereoscopic display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stereoscopic display capable of providing stereoscopic images that a plurality of people can observe without using special eyeglasses from arbitrary directions and that can sufficiently obtain a stereoscopic presence of an object. <P>SOLUTION: The stereoscopic display 1 is configured such that it has a box-shape by bonding a plurality of quadrangular element display surfaces 2. The stereoscopic image 3 is presented in a globular region (a virtual sphere), that is, the virtual space enclosed with the element display surfaces 2. Every element display surface 2 has a layered structure comprising a planar spatial light modulator 21, a planar lens array and a planar tactile sensor. The lens array consists of a plurality of convex lenses that can control the direction of light beam; and the lens array has a function of reproducing the state of light that goes from the spatial light modulator to various directions. Every convex lens in the lens array is set to satisfy a predetermined condition. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a stereoscopic display for presenting a stereoscopic image.

  A stereoscopic display for presenting a stereoscopic image is roughly classified into a volume display and a stereoscopic display.

  The volume display is a method for projecting an image into a space by some method. For example, there is a method of projecting an image on a plate that rotates at high speed. A volume display can be simultaneously observed by a plurality of people, but many require a relatively large projection system and mechanical structure.

  On the other hand, a stereoscopic display projects an object contained in a viewing volume (a cone having a viewpoint as a vertex and an image presentation surface in a cross section) onto the image presentation surface, and an image that can be seen through the image presentation surface to both eyes. By presenting, the image is stereoscopically viewed.

  In particular, integral photography (IP) is one of the technologies that enables stereoscopic images to be observed with the naked eye. In integral photography, a lens array including a plurality of convex lenses is arranged on the image presentation surface as a light controller, and an element image for reproducing a stereoscopic image is presented at a focal position under each convex lens. The light emitted from each pixel of each element image is emitted so as to be directed only in a specific direction by the effect of the convex lens. Since the lens array arranged on the image presentation surface acts organically to create a discrete light space, the light state according to the viewing volume from an arbitrary viewpoint is reproduced.

  Such a stereoscopic display can be reduced in size by using an LCD (Liquid Crystal Display) or the like on the image presentation surface. It is difficult to obtain the presence of a three-dimensional object.

Patent Document 1 describes a three-dimensional image display system in which a plurality of three-dimensional image display devices are combined. Each three-dimensional image display device includes a display unit in which pixels are arranged in a matrix on the display surface, and a plurality of light beam control units that restrict light beams from the pixels of the display unit and direct light beams to an observation region. A unit. According to this three-dimensional image display system, a three-dimensional image can be observed by a plurality of people. It is also possible to observe a three-dimensional image.
JP 2006-98775 A

  As described above, in the three-dimensional image display system described in Patent Document 1, observation by a plurality of persons is possible, and a three-dimensional image can be observed by wrapping around.

  However, in the three-dimensional image display system of Patent Document 1, display is limited at the outer peripheral portion of each display surface. Specifically, when two or more display surfaces are observed simultaneously from an oblique direction, a portion where a stereoscopic image cannot be seen occurs. Therefore, the presence of a three-dimensional object cannot be obtained sufficiently.

  An object of the present invention is to provide a three-dimensional display that presents a three-dimensional image that can be observed by a plurality of people from any direction without using special glasses and can sufficiently obtain the presence of a three-dimensional object. That is.

The three-dimensional display according to the present invention includes a plurality of element display surfaces that form a three-dimensional outer surface and a control unit that controls display of the plurality of element display surfaces, and the plurality of element display surfaces generate a plurality of light. A spatial light modulator composed of a plurality of light beam controllers and a light beam controller array configured to control the direction of light generated from each pixel of the spatial light modulator, and the control means includes a plurality of light control elements. The spatial light modulator is controlled so that a stereoscopic image is presented in the virtual sphere in the space surrounded by the element display surface, and the observer's viewpoint is concentric with the virtual sphere and formed outside the multiple element display surfaces And r is the radius of the phantom sphere, D is a vector from the center of the phantom sphere to the center of each ray controller, and θ is a tangent drawn from the center of each ray controller to the phantom sphere. The angle formed by the vector D, and p is the spatial light modulator And z is the distance from the center of the element display surface to the spherical surface, e is the distance between the eyes of the observer, f is the distance from each light controller to the spatial light modulator, and α is The distance f from each light controller to the spatial light modulator, the element display surface, where N is the number of pixels assigned to each light controller, and the angle between the direction perpendicular to the element display surface and the vector D And the number N of pixels assigned to each light controller,
θ = sin ⁻¹ (r / | D |) (1)
f ≧ pz / e (2)
pN ≧ f · tan (α + θ) −f · tan (α−θ) (3)
Is set so as to satisfy.

  In the three-dimensional display according to the present invention, a three-dimensional outer surface is formed by a plurality of element display surfaces. Each element display surface includes a spatial light modulator and a light controller array. The spatial light modulator is controlled by the control means so that a stereoscopic image is presented on a virtual sphere in a space surrounded by a plurality of element display surfaces.

  In this case, the distance f from each light controller to the spatial light modulator, the position of each light controller on the element display surface, and the number N of pixels assigned to each light controller are given by the above equations (1) to (3). ) Is set to satisfy.

  From the above equation (1), the angle θ formed by the tangent drawn from the center of each ray controller to the virtual sphere and the vector D is obtained. Further, the distance f from each light beam controller to the spatial light modulator is obtained from the above equation (2). Furthermore, the number of pixels assigned to each light ray controller is obtained from the above equation (3).

  Thereby, it is possible to observe a stereoscopic image by a plurality of persons from an arbitrary direction without using special glasses. Further, the observer can stereoscopically view a stereoscopic image presented in a virtual sphere in a space surrounded by a plurality of element display surfaces with the naked eye. Therefore, a sufficient presence of a three-dimensional object can be obtained.

  Each of the plurality of element display surfaces may have a flat quadrangular shape, and the plurality of element display surfaces may form a rectangular parallelepiped.

  In this case, each element display surface can be easily produced, and a three-dimensional outer surface can be easily produced by a plurality of element display surfaces. Further, the distance f from each light controller to the spatial light modulator, the position of each light controller on the element display surface, and the number N of pixels assigned to each light controller are given by the above equations (1) to (3). When satisfied, the stereoscopic image presented in the virtual sphere can be observed from an arbitrary direction.

  Each of the plurality of element display surfaces may have a planar square shape, and the plurality of element display surfaces may form a cube. In this case, it becomes easy to design and manufacture each light controller.

  The spatial light modulator may include a planar matrix display element. In this case, each element display surface can be easily manufactured.

  The stereoscopic display further includes a tactile sensor provided along the element display surface, and the control means includes a spatial light modulator such that a stereoscopic image presented in the virtual sphere changes in response to an output signal of the tactile sensor. You may control.

  In this case, the observer can touch the element display surface surrounding the stereoscopic image or can hold it in his / her hand, so that the stereoscopic shape of the stereoscopic image can be simulated and the stereoscopic image can be observed. The direction can be operated by hand. Further, when the operator touches any part of the element display surface from any direction, the corresponding part of the stereoscopic image presented in the virtual sphere changes. Thereby, the observer can obtain a feeling of directly touching the object represented by the stereoscopic image through the change of the stereoscopic image in response to the act of touching the element display surface. As a result, the presence of a tactile object can be obtained.

  The plurality of light controllers may be a plurality of lenses, and the light controller array may be a lens array. In this case, a bright stereoscopic image is presented.

  According to the present invention, an observer can stereoscopically view a stereoscopic image presented in a virtual sphere in a space surrounded by a plurality of element display surfaces from any direction with the naked eye. Therefore, a sufficient presence of a three-dimensional object can be obtained.

(1) Configuration of stereoscopic display FIG. 1 is a schematic external view showing a stereoscopic display according to an embodiment of the present invention.

  As shown in FIG. 1, the stereoscopic display 1 is configured in a box shape by combining a plurality of rectangular element display surfaces 2. In the present embodiment, the three-dimensional display 1 is configured in a cube by six square element display surfaces 2. A stereoscopic image 3 is presented in a spherical region (hereinafter referred to as a virtual sphere) in a virtual space surrounded by the element display surface 2.

  FIG. 2 is a schematic plan view showing the element display surface 2 constituting the stereoscopic display 1. FIG. 3 is a schematic plan view showing the element display surface 2 constituting the stereoscopic display 1.

  As shown in FIGS. 2 and 3, the element display surface 2 is configured by a laminated structure of a planar spatial light modulator 21, a planar lens array 22, and a planar tactile sensor 23.

  The spatial light modulator 21 includes a matrix display element that can present colors in a matrix. The spatial light modulator 21 has a plurality of pixels arranged in a matrix. As the spatial light modulator 21, for example, a liquid crystal display (LCD) or an organic electroluminescence (EL) display can be used. Alternatively, as the spatial light modulator 21, a projector and a screen may be used in combination.

  The lens array 22 includes a plurality of convex lenses 220 that can control the direction of light rays, and has a function of reproducing the state of light from the spatial light modulator 21 in various directions. The plurality of lenses 220 of the lens array 22 are arranged in a matrix.

  The direction of the light beam from the plurality of pixels of the spatial light modulator 21 is controlled by each convex lens 220 of the lens array 22. Each convex lens 220 is assigned a pixel group. Each convex lens 220 is arranged so that the direction of light rays from only the assigned pixel group can be controlled.

  The number of light rays and the direction of light rays that can be controlled by the lens array 22 are the optical design of the convex lens 220 such as the number of pixels assigned to each convex lens 220, the distance between the convex lens 220 and the pixel, and the focal length of the convex lens 220. It depends on etc. The arrangement of the convex lens 220 and the design of characteristics will be described later.

  As shown in FIG. 3, the convex lens 220 of the lens array 22 controls light traveling in various directions from the pixels Pa, Pb, Pc, and Pd of the spatial light modulator 21 in directions indicated by dotted lines.

  In the present embodiment, a sheet-like transparent tactile sensor 23 is provided on the lens array 22. For example, as the tactile sensor 22, a sheet-like light detection element that detects a change in the light transmission state to the optical fiber, a sheet-like variable capacitance element that detects a change in the capacitance of the contact portion, or a contact depending on the energization state between the electrodes A conductive sheet or the like that detects the above can be used.

  Further, as the tactile sensor 23, for example, a tactile sensor array may be used. The tactile sensor array includes a plurality of tactile sensor elements arranged in a matrix. As the tactile sensor element, various contact sensors that can detect that a person or an object has touched can be used.

  Further, a tactile sensor constituted by a plurality of tactile sensor elements embedded between the convex lenses 220 of the lens array 220 may be used. For example, as the tactile sensor element, a piezoelectric element (piezo element) that detects a voltage change due to the piezoelectric effect, a strain gauge that detects strain, and a variable capacitance element that detects a change in capacitance can be used. It is also possible to use a light detection element such as a photodiode that detects light blocked by a finger, a heat detection element that detects a temperature change, or the like.

  In the present embodiment, the tactile sensor 23 outputs a detection signal indicating the magnitude of the load when the observer touches, the direction of the load, and the position where the load is applied.

  Further, the observer can touch the surface of the stereoscopic display 1. In particular, in the present embodiment, the three-dimensional display 1 is formed so as to have a size and weight that can be held by an observer.

(2) Image Data Creation Method Next, an image data creation method for presenting the stereoscopic image 3 on the stereoscopic display 1 will be described. FIG. 4 is a diagram for explaining a method of creating image data for presenting the stereoscopic image 3.

  A solid shape 30 to be visualized is defined in a virtual sphere inside the element display surface 2. This three-dimensional shape 30 is represented by three-dimensional shape data. A light ray traveling in an arbitrary direction at an arbitrary point on the surface of the three-dimensional shape 30 is considered. The positional relationship between the element display surface 2 and the three-dimensional shape 30 is uniquely determined by data definition.

  The position (coordinate) of the intersection when each light ray intersects the element display surface 2, the angle between the light ray and the element display surface 2, and the color are obtained. Further, it is determined at which position on which element display surface 2 each light ray intersects. Finally, image data for displaying the color of the intersection point on each pixel of the spatial light modulator 21 is created so as to reproduce the light beam traveling in the direction of the angle by the lens array 22.

  Ideally, the position, angle, and color of the above intersection are obtained for light rays traveling in all directions from the entire surface of the three-dimensional shape 30, and image data representing an image to be displayed on each element display surface 2 is created. Actually, the virtual sphere in the space surrounded by the element display surface 1 is discretized into a plurality of voxels, and the direction of light rays emitted from each voxel is discretized. In the present embodiment, the direction of light emitted from each voxel is controlled by the lens array 22 so as to be discretized.

  If one voxel of the phantom sphere inside the element display surface 2 is a part of the three-dimensional shape 30, a light ray directed from the voxel in a discretized direction is obtained. In this way, the intersections between the light beams traveling in a plurality of directions discretized from each of the plurality of voxels on the surface of the three-dimensional shape 30 and the element display surface 2 are obtained, and the angle between the light beam and the element display surface 2; And voxel colors are obtained, and image data is created based on their intersections, angles, and colors.

  For example, as shown in FIG. 4, a light beam emitted from one voxel b <b> 1 on the surface of the three-dimensional shape 30 is controlled by the convex lens 220 of the lens array 22 in the direction of the dotted arrow. Image data is created so that the color of the voxel b1 is displayed at the pixel at the intersection of these rays and the element display surface 2.

  Light rays emitted from other voxels b2 on the surface of the three-dimensional shape 30 are controlled by the convex lens 220 of the lens array 22 so as to go in the direction of the solid arrow. Image data is created so that the color of the voxel b2 is displayed on the pixel at the intersection of these rays and the element display surface 2.

  The above description has been made for ease of understanding, but in reality, the reproducible rays are limited by the relationship between each convex lens 220 of the lens array 22 and the number of pixels of the spatial light modulator 21. The reverse algorithm to that described above is used. That is, the light beam reproducible by each convex lens 220 of the lens array 22 is traced back through the pixels of the spatial light modulator 21 to obtain the color of the voxel at the intersection with the three-dimensional shape 30 to be presented. Determine the color to be displayed.

  When one light beam reproducible by the convex lens 220 of the lens array 22 intersects a plurality of voxels of the three-dimensional shape 30, the color of the voxel closer to the element display surface 2 is determined as the color to be displayed on the pixel. . This is because a point located in the back as viewed from the observer is hidden by a point located in front. For example, as shown in FIG. 4, when one light beam reproducible by the convex lens 220 of the lens array 22 intersects a plurality of voxels b2 and b3 of the three-dimensional shape 30, the voxel b3 closer to the element display surface 2 Is determined as the color to be displayed on the pixel.

  In this way, image data for displaying the color of each voxel on the surface of the three-dimensional shape 30 on a plurality of pixels on the element display surface 1 is created. By displaying an image on a plurality of pixels of the spatial light modulator 21 based on the image data, the light rays from the three-dimensional shape 30 are reproduced as a result.

  FIG. 5 is a diagram for explaining an image displayed on the spatial light modulator 21 of the stereoscopic display based on the image data.

  For example, an image when the stereoscopic shape is viewed from the observation point V1 is displayed on the pixel “A” of the spatial light modulator 21. In addition, an image when the stereoscopic shape is viewed from the observation point V2 is displayed on the pixel “B” of the spatial light modulator 21. Thereby, the observer can see the three-dimensional shape from different angles when the eye is moved from the observation point V1 to the observation point V2.

  Thus, although the stereoscopic display according to the present embodiment is a multi-view stereoscopic display, as a result, a stereoscopic image 3 equivalent to a volume display can be presented.

(3) Configuration of Convex Lens 220 FIG. 6 to FIG. 9 are diagrams for explaining light beam control conditions necessary for displaying the stereoscopic image 3 that can be observed from an arbitrary direction. 6 to 9, the direction perpendicular to the element display surface 2 is taken as the Z axis.

  As shown in FIG. 6, a virtual sphere S having a center of O and a radius of r is considered as a region for displaying the stereoscopic image 3.

  First, let L be the center of the convex lens 220. A vector connecting the center O of the phantom sphere S and the center L of the convex lens 220 is represented by D. The light beam reproduction range to be handled by the convex lens 220 is a cone having an apex angle 2θ with the center L of the convex lens 220 as a vertex and the vector D as a central axis. The angle θ is expressed by the following formula.

θ = sin ⁻¹ (r / | D |) (1)
Next, let the focal length of the convex lens 220 be f. In FIG. 7, the convex lens 220 positioned at the center of the element display surface 2 is referred to as a convex lens 220 a, and the convex lens 220 positioned near the outer periphery of the element display surface 2 is referred to as 220 b. The lens array 22 is disposed on the plane B, and the spatial light modulator 21 is disposed on the plane C that is separated from the lens array 22 by a distance f. The plane C is parallel to the plane B. Further, a plane P that is a distance z away from the plane B is considered. The plane P is parallel to the plane B.

  In a general planar stereoscopic display, the observer is defined to be on a plane P parallel to the lens array 22. Let p be the size (diameter or width) of the pixel of the spatial light modulator 21. The image of the pixel is magnified z / f times on the plane P by the convex lenses 220a and 220b. The size (diameter or width) i of the pixel image on the plane P is expressed by the following equation.

i = (z / f) · p (2a)
Next, the conditions for binocular stereopsis will be examined. In order to enable binocular stereoscopic vision, it is necessary to have different images in both eyes. The distance e between the human eyes is about 62 mm to 64 mm. Different images appearing in both eyes is equivalent to the arrival of different light rays from the convex lens 220 at the viewpoint positions of the right eye and the left eye separated by a distance e. That is, it is necessary for different rays to reach the position separated by the distance e on the plane P by the convex lens 220. For this purpose, the image size i on the plane P must be less than or equal to the distance e.

  Since the stereoscopic display 1 according to the present embodiment is assumed to be observed from an arbitrary direction, it is assumed that a spherical surface E whose center is O is defined and the viewpoint position is on the spherical surface E. The distance between the center point of the element display surface 2 (plane B) and the spherical surface E is z.

  Here, by satisfying the following conditions, the stereoscopic image presented in the virtual sphere S can be stereoscopically viewed when the observer's viewpoint is within the spherical surface E. When the observer's viewpoint is outside the spherical surface E, the observer recognizes the stereoscopic image presented in the virtual sphere S as a planar image. For example, if it is estimated that the position that the observer often observes is a position that is about 35 cm away from the center O of the phantom sphere S, the radius of the spherical surface E may be set to a large 40 cm.

  In addition, the stereoscopic perception by binocular stereoscopic vision decreases as the observer moves away from the observation target. Therefore, it is reasonable to limit the stereoscopic view range of the stereoscopic image within the spherical surface E, and there is no problem.

Let i ′ be the size of the image of the pixel projected onto the spherical surface E by the convex lens 220. The size i ′ of the pixel image changes according to the position of the convex lens 220. For example, the image size i ₁ ′ projected by the convex lens 220b on the spherical surface E is smaller than the image size i ₀ ′ projected by the convex lens 220a. Since the pixels are arranged at equal intervals on the plane C parallel to the plane B, the image size i ′ is maximized in the vicinity of the point Q where the spherical surface E and the plane P are in contact.

In order to enable binocular stereoscopic vision from an arbitrary direction, it is necessary for different rays to reach the position separated by the distance e on the spherical surface E by the convex lens 220. For this purpose, the image size i ′ on the spherical surface E must be less than or equal to the distance e. Therefore, when the case where the size i ′ of the image on the spherical surface E is the largest (when i ′ = i ₀ ′) is considered as a reference, the following expression must be satisfied.

e ≧ i ₀ ′ (2b)
Further, since i ₀ ′ ≈i, the following equation is established from the above equation (2a).

i ₀ ′ = pz / f (2c)
From the above equations (2b) and (2c), the following equation is derived.

e ≧ pz / f (2d)
From the above equation (2d), the focal length f of the convex lens 220 is determined as follows.

f ≧ pz / e (2)
Next, as shown in FIG. 8, the angle between the Z axis and the vector D is α. The number N of pixels necessary for emitting light within the range of the angle 2θ with the vector D as the central axis is obtained as follows. Let s1 and s2 be the intersections of the outermost ray and the plane C in the conical ray group forming the angle 2θ, and let s0 be the intersection of the straight line in the Z-axis direction passing through the center L of the convex lens 220 and the plane C. The distance between the two points s0 and s1 is f · tan (α + θ), and the distance between the two points s0 and s2 is f · tan (α−θ). Therefore, the distance between the two points s1 and s2 is f · tan (α + θ) −f · tan (α−θ). In this case, pN needs to be equal to or greater than the distance between the two points s1 and s2. Therefore, the following equation holds.

pN ≧ f · tan (α + θ) −f · tan (α−θ) (3)
From the above consideration, when the stereoscopic image 3 is displayed in the virtual sphere S of the stereoscopic display 1, each convex lens 220 of the element display surface 2 is set so as to satisfy the conditions of the following expressions (1) to (3). Need to design. In this case, it is assumed that the observer's viewpoint is inside the spherical surface E.

θ = sin ⁻¹ (r / | D |) (1)
f ≧ pz / e (2)
pN ≧ f · tan (α + θ) −f · tan (α−θ) (3)
In the above equation (1), r is the radius of the phantom sphere S, D is a vector from the center O of the phantom sphere S to the center L of the convex lens 220, and θ is drawn from the center L of the convex lens 220 to the phantom sphere S. The angle formed by the tangent line and the vector D. The angle θ is obtained from the above equation (1).

  In the above equation (2), p is the size of the pixel of the spatial light modulator 21, z is the distance from the center of the element display surface 2 to the spherical surface E, and e is the distance between the eyes of the observer. F is the focal length of the convex lens 220. The focal length f of the convex lens 220 is obtained from the above equation (2).

  Since the plane B and the plane C are parallel, the focal lengths f of all the convex lenses 220 are equal.

  In the above equation (3), α is an angle formed by a direction perpendicular to the element display surface 2 and the vector D, and N is the number of pixels assigned to the convex lens 220. From the above equation (3), the number N of pixels allocated to the convex lens 220 is obtained. N is a natural number.

  At the time of designing and manufacturing the three-dimensional display 1, first, the dimensions of the element display surface 2 are determined. Next, the radius r of the phantom sphere S is determined from the dimensions of the element display surface 2. Thereby, the angle θ is determined by the above equation (1). Further, the radius of the spherical surface E is determined.

  Thereafter, in order from the center of the element display surface 2 to the outside, the focal length f of each convex lens 220 is determined by the above equation (2), and the number N of pixels assigned to the convex lens 220 and the convex lens by the above equation (3). The position of 220 is determined. In this case, the position of each convex lens 220 is determined so that the pixels assigned to each convex lens 220 do not overlap.

(4) Configuration and operation of control system of stereoscopic display FIG. 9 is a block diagram showing the configuration of the control system of the stereoscopic display according to the present embodiment.

  As shown in FIG. 9, the control system of the stereoscopic display includes a control unit 10, a shape data storage unit 11, a spatial light modulator 21, and a tactile sensor 23.

  The control unit 10 includes a CPU (Central Processing Unit) and a storage device such as a semiconductor memory. A display control program is stored in the storage device. The shape data storage unit 11 includes a data storage medium such as a hard disk or a memory card, and stores stereoscopic shape data representing the shape of a stereoscopic image to be presented in the virtual sphere.

  The CPU of the control unit 10 creates image data based on the solid shape data stored in the shape data storage unit 11 by executing a display control program stored in the storage device, and displays the data based on the image data. Is supplied to the spatial light modulator 21, and the three-dimensional shape data is corrected based on the detection signal of the touch sensor 23.

  The control unit 10 and the shape data storage unit 11 may be provided inside a space surrounded by the element display surface 1. Alternatively, the control unit 10 and the shape data storage unit 11 may be provided outside the space surrounded by the element display surface 1. In this case, a control signal is given from the control unit 10 to the spatial light modulator 21 by wired or wireless communication, and a detection signal is given from the touch sensor 23 to the control unit 10 by wired or wireless communication. Further, one of the control unit 10 and the shape data storage unit 11 may be provided inside the space surrounded by the element display surface 1, and the other may be provided outside the space surrounded by the element display surface 1.

  Next, the operation of the stereoscopic display 1 according to the present embodiment will be described. FIG. 10 is a flowchart showing the operation of the control unit 10 of the stereoscopic display according to the present embodiment.

  The control unit 10 executes the operation of the flowchart of FIG. 10 according to the display control program stored in the storage device.

  Note that the shape data storage unit 11 stores stereoscopic shape data representing the shape of the stereoscopic image 3.

  First, the control unit 10 loads solid shape data from the shape data storage unit 11 (step S1). Then, the control unit 10 creates image data based on the solid shape data (step S2). Further, the control unit 10 causes the spatial light modulator 21 to display an image based on the image data (step S3). Thereby, as shown in FIG. 1, the three-dimensional image 3 is presented on the virtual sphere of the three-dimensional display. In this case, the operator and other observers can visually see the stereoscopic image 3 in the virtual sphere.

  The operator can touch the element display surface 1 of the stereoscopic display. The controller 10 determines whether or not a detection signal is output from the touch sensor 23 (step S4).

  When the detection signal is output from the touch sensor 23, the control unit 10 corrects the three-dimensional shape data based on the detection signal (step S5). In this case, the control unit 10 determines the magnitude of the load, the direction of the load, and the position of the load when the operator touches the tactile sensor 23 from the detection signal, and the magnitude of the load, the direction of the load, and the load The three-dimensional shape data is corrected so that the three-dimensional image 3 changes in accordance with the contact with the element display surface 1 based on the positions of

  Then, the control unit 10 returns to step S2 and creates image data based on the corrected three-dimensional shape data. Further, the control unit 10 causes the spatial light modulator 21 to display an image based on the image data (step S3). As a result, the stereoscopic image 30 viewed by the operator and other observers changes.

  For example, when the operator presses a part of the element display surface 2 with a finger, the part of the stereoscopic image 3 near the part is deformed. The mode of change of the stereoscopic image 3 when it contacts a part of the element display surface 2 is not limited to the above example, and may be another mode of change as long as it is any change of the element display surface 2.

  In step S4, if no detection signal is output from the touch sensor 23, the control unit 10 returns to step S3.

(5) Effect of this Embodiment In the three-dimensional display 1 according to this embodiment, each convex lens 220 on the element display surface 2 so as to satisfy the conditions of the above formulas (1), (2), and (3). Is designed, the stereoscopic image 3 presented in the virtual sphere S can be observed from an arbitrary direction. In addition, a pseudo volume display is realized in which a stereoscopic image 3 presented in the virtual sphere S can be stereoscopically viewed by a plurality of observers. Therefore, a sufficient presence of a three-dimensional object can be obtained.

  Furthermore, since the 3D display 1 that presents the 3D image 3 can be held in the hand, the 3D shape of the 3D image 3 can be simulated and the direction in which the 3D image 3 is observed can be controlled. Can be operated with. Further, when the operator touches any part of the element display surface 2 from any direction, the shape of the corresponding part of the stereoscopic image 3 changes. Thereby, the operator can obtain a feeling of directly touching the object represented by the stereoscopic image 3 through the deformation of the stereoscopic image 3 in response to the act of touching the element display surface 2. As a result, the presence of a tactile object can be obtained.

(6) Simulation of stereoscopic display 1 The appearance of the stereoscopic image on the stereoscopic display of the example and the stereoscopic image on the stereoscopic display of the comparative example were evaluated by simulation.

  The stereoscopic display of the example has the convex lens 220 in the above embodiment, and the stereoscopic display of the comparative example has a fly-eye lens used in general integral photography (IP). In this simulation, the radius r of the phantom sphere S is 30 mm, the length of one side of the element display surface 2 is 70 mm, and the distance z is 350 mm.

  FIG. 11 is a diagram showing the simulation result of the comparative example, and FIG. 12 is a diagram showing the simulation result of the example.

  FIGS. 11 and 12A are views when the stereoscopic display is observed from a direction perpendicular to the front, and FIGS. 11B and 12B are views when the stereoscopic display is observed from a slightly oblique direction. (C) The appearance when the stereoscopic display is observed from a direction of 45 degrees with respect to the front and side surfaces. (D) is the appearance when the stereoscopic display is observed from a direction of 45 degrees with respect to the front, sides, and top surface. Show how.

  In FIG. 11 and FIG. 12, the white part indicates a lens in which a correct image is seen, and the black part is out of the reproduction range of light rays from the pixel, or the image for another viewpoint is visible. Indicates a lens.

  As shown in FIG. 11, in the stereoscopic display of the comparative example, a stereoscopic image can be seen when viewed from the front. However, when two or three surfaces are observed simultaneously, part or all of the stereoscopic image is displayed. I can't see it. Thus, in the stereoscopic display of the comparative example, there is a lens that cannot present a stereoscopic image depending on the viewing direction.

  On the other hand, as shown in FIG. 12, the stereoscopic display of the embodiment can see a stereoscopic image when viewed from any direction. In the stereoscopic display of the embodiment, each lens can present a stereoscopic image in the phantom sphere S even when observed from an arbitrary direction.

  From the above results, it can be seen that in the stereoscopic display of the example, the stereoscopic image presented in the virtual sphere S can be observed by a plurality of people from an arbitrary direction.

(7) Other Embodiments In the above embodiment, the convex lens array 220 is used as the light controller, but a pinhole array having a plurality of pinholes or a diffraction grating array having a plurality of diffraction gratings is used as the light controller. May be used. In this case, the distance between the pinhole of the pinhole array or the diffraction grating of the diffraction grating array and the spatial light modulator 21 corresponds to the focal length f in the above embodiment.

  In the above-described embodiment, the plurality of convex lenses 220 are arranged in a matrix. However, as shown in FIG. 13, the plurality of convex lenses 220 may be arranged in a fly's eye shape without a gap.

(8) Application Example The three-dimensional display according to the present invention can be used for displaying an object that is confirmed from an arbitrary angle for the hand and that is requested to be observed by a plurality of persons at the same time.

  (A) At the time of inspection of a product, an image of the product is read as data with a scanner, and a stereoscopic image of the product is presented on a stereoscopic display based on the data. Thereby, the presence or absence of defects such as scratches on the surface of the product can be inspected nondestructively using the stereoscopic image.

  (B) During baggage inspection at an airport, a three-dimensional image of baggage can be presented on a three-dimensional display.

  (C) Since the three-dimensional display can be actually rotated or changed in position by hand, it can be used as an interface whose function is clearly understood.

  (D) In the medical field, a three-dimensional image of an organ model can be presented on a three-dimensional display for informed consent or technology improvement education. In addition, ultrasonic scanner or CT (computer tomography) data or the like can be presented as a stereoscopic image and used for medical examination.

  (E) In daily life, it can be used to present a stereoscopic image of a stereoscopic videophone. Moreover, it can also be used as a 3D photo frame for presenting 3D photos.

  (F) In the field of entertainment, the stereoscopic display can be used for moving image stereoscopic display of frames such as chess, presentation of a stereoscopic image of a Rubik's cube, and the like.

  (G) In the field of advertising, it is possible to present an advertisement using a stereoscopic image that can be picked up by hand and explained while pointing to another person.

  (H) In a teleconference scene, the shape data of a prototype can be transmitted over a network, and the shape data can be presented as a stereoscopic image on a stereoscopic display. In this case, it is possible to examine the product by holding the stereoscopic image by a plurality of people and holding it in hand.

  The present invention can be used as a three-dimensional display that presents various three-dimensional shapes.

1 is a schematic external view showing a stereoscopic display according to an embodiment of the present invention. It is a typical top view which shows an element display surface. It is typical sectional drawing which shows an element display surface. It is a figure for demonstrating the production method of the image data for showing a stereo image. It is a figure for demonstrating the image displayed on the spatial light modulator of a three-dimensional display based on image data. It is a figure for demonstrating the conditions of light control required in order to display the stereo image which can be observed from arbitrary directions. It is a figure for demonstrating the conditions of light control required in order to display the stereo image which can be observed from arbitrary directions. It is a figure for demonstrating the conditions of light control required in order to display the stereo image which can be observed from arbitrary directions. It is a block diagram which shows the structure of the control system of the three-dimensional display which concerns on this Embodiment. It is a flowchart which shows operation | movement of the control part of the three-dimensional display which concerns on this Embodiment. It is a figure which shows the simulation result of a comparative example. It is a figure which shows the simulation result of an Example. It is a schematic diagram which shows the other example of arrangement | positioning of the convex lens of a lens array.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stereo display 2 Element display surface 3 Stereo image 10 Control part 11 Shape data storage part 21 Spatial light modulator 22 Lens array 23 Tactile sensor 30 Three-dimensional shape 220 Convex lens r Radius of virtual sphere D From center of virtual sphere to center of each lens Vector θ of the angle p formed by the tangent drawn from the center of each lens to the phantom sphere and the vector D, the size of the pixel of the spatial light modulator z, the distance from the center of the element display surface to the spherical surface e, between the eyes of the observer The distance f is the focal length α of each lens. The angle N between the direction perpendicular to the element display surface and the vector D is the number of pixels assigned to each lens. V1 Observation point V2 Observation points Pa, Pb, Pc, Pd Pixels b1, b2, b3 voxels

Claims (6)

A plurality of element display surfaces forming a three-dimensional outer surface;
Control means for controlling display of the plurality of element display surfaces,
The plurality of element display surfaces are:
A spatial light modulator composed of a plurality of pixels that generate light;
A light controller array comprising a plurality of light controller, and controlling a direction of light generated from each pixel of the spatial light modulator,
The control means controls the spatial light modulator so that a stereoscopic image is presented in a virtual sphere of a space surrounded by the plurality of element display surfaces;
An observer's viewpoint is concentric with the phantom sphere and is inside a spherical surface formed outside the plurality of element display surfaces, r is a radius of the phantom sphere, and D is a ray from the center of the phantom sphere. A vector to the center of the controller, θ is an angle formed by a tangent drawn from the center of each ray controller to the phantom sphere and the vector D, p is a pixel size of the spatial light modulator, and z is an element The distance from the center of the display surface to the spherical surface, e the distance between the eyes of the observer, f the distance from each light controller to the spatial light modulator, and α perpendicular to the element display surface When the angle between the direction and the vector D is used, and N is the number of pixels assigned to each light controller, the distance f from each light controller to the spatial light modulator, each light control on the element display surface The position of the child and the number N of pixels assigned to each light control element is
θ = sin ⁻¹ (r / | D |) (1)
f ≧ pz / e (2)
pN ≧ f · tan (α + θ) −f · tan (α−θ) (3)
3D display characterized by being set to satisfy the above. The three-dimensional display according to claim 1, wherein each of the plurality of element display surfaces has a planar quadrangular shape, and the plurality of element display surfaces form a rectangular parallelepiped. The three-dimensional display according to claim 1 or 2, wherein each of the plurality of element display surfaces has a planar square shape, and the plurality of element display surfaces form a cube. The three-dimensional display according to claim 1, wherein the spatial light modulator includes a planar matrix display element. A tactile sensor provided along the element display surface;
The said control means controls the said spatial light modulator so that the three-dimensional image shown in the said virtual sphere changes in response to the output signal of the said tactile sensor. The three-dimensional display of crab. The three-dimensional display according to claim 1, wherein the plurality of light control elements are a plurality of lenses, and the light control element array is a lens array.

Images