JP2016018118A - Light-ray controller for presenting stereoscopic images and stereoscopic display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin and compact light-ray controller and stereoscopic display.SOLUTION: The present invention provides a light-ray controller 1 having the following basic configuration. a) The light-ray controller 1 has a cylindrical or conical shape extending in a Z-axis direction with a circular or polygonal cross-section centered around the Z-axis. b) A peripheral wall is translucent. c) The peripheral wall diffusely transmits incident light rays in a ridge-line direction, and transmits incident light rays straight, substantially without diffusing, in a circumferential direction centered around the Z-axis. d) A lens plate is configured such that a refraction angle of output light relative to incident light gradually increases from bottom to top.SELECTED DRAWING: Figure 14

Description

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

  Many people gather around the table to collaborate. A table is regarded as a tool for collaborative work, and various studies have been conducted to support collaborative work using this tool using a computer. For example, research on CSCW (Computer Supported Cooperative Work) and groupware.

  Advantages of digitizing work on the table include the ability to electronically record the work process and the ability to share information between remote locations. An image displayed in the conventional research is projected onto a table by a projector, or the table itself is composed of a display such as an LCD (Liquid Crystal Display). In either case, a two-dimensional planar image is displayed.

In such a planar image, only information such as a document can be presented, and information of a three-dimensional shape cannot be presented. Also, when a single planar image is displayed, the information is reversed depending on the position of the person surrounding the table, which is very difficult to see.
In order to solve the above problem, a method of presenting a stereoscopic image on a table has been proposed. For example, in the stereoscopic display described in Patent Document 1, a set of virtual point light sources is formed on a table by light beams emitted from a plurality of projectors. Thereby, a stereoscopic image is presented on the table.

JP 2010-32952 A JP 2006-78645 A International Publication No. 2009/057522 JP 2005-242378 A

In the basic technique disclosed in Patent Document 1, as shown in FIG. 23, the projector 2 is positioned so as to face the conical light beam controller 1 from obliquely below. For this reason, in order to increase the screen size, a projection distance is required, and the upper and lower thicknesses of the apparatus are increased.
In order to reduce the thickness, it is also possible to bend the projection optical axis with a mirror M as shown in FIG. In this case, a donut-shaped flat mirror M that covers the periphery of the light beam controller 2 is arranged below the light beam controller 2, and the projector 2 is directed to the mirror M obliquely below. And the reflected light reflected toward the mirror M from the upper side is irradiated to the light beam controller 1 diagonally upward. However, a very large mirror M that spreads around the light beam controller 2 is required.

In addition, there are Patent Literatures 2 to 4 as prior literatures related to a technique for projecting from a projector onto a screen.
Here, Patent Document 2 relates to an optical engine of a rear projection type monitor. In the rear professional optical engine, light emitted from one projector is folded back by a large reflecting mirror and displayed. This can be applied to a projector having one projector, but cannot be applied to a case where there are a plurality of projectors.

Patent Document 3 relates to a scanning projection apparatus, and aims to correct trapezoidal distortion and curvature of field with a mirror optical system. However, since the basic shape of the screen is a conical shape or a polygonal shape, and the projector is arranged facing the screen, such distortion correction is not required.
Further, Patent Document 4 relates to a rear projection television and a projection method thereof, and discloses a planar screen in which a Fresnel lens and a lenticular lens are combined. However, the present invention is only limited to a rear projection type display having a large number of mirror optical systems between the projector and the screen.

  The present invention provides a light controller and a stereoscopic display that are thin and compact in size.

  The light beam controller of the present invention has a circular or polygonal cross section centered on the axis Z, is cylindrical or conical along the axis Z direction, has a translucent wall, and has a translucent wall. Is a light controller formed such that incident light is diffused and transmitted in the ridge line direction, and is transmitted in a straight line without substantially diffusing in the circumferential direction around the axis Z. The lens plate includes a lens plate that gradually increases the refraction angle of the emitted light with respect to the incident light from below to above on the surface of the peripheral wall.

  The stereoscopic display according to the present invention is a stereoscopic display for presenting a stereoscopic image based on stereoscopic shape data so that at least a part of the stereoscopic image is located in a space on a predetermined reference plane, on the reference plane. A light beam controller having an opening and a peripheral wall below the reference surface; and a light beam group composed of a plurality of light rays below the reference surface and from outside the light beam controller. A plurality of light generators arranged around the light controller so as to irradiate the outer peripheral surface of the peripheral wall, respectively, and a light beam generated by the plurality of light generators based on the three-dimensional shape data. Control means for controlling the plurality of light generators so that an image is presented, wherein the control means is configured such that at least a part of the stereoscopic image is above the opening of the light controller. As shown, the plurality of light generators are controlled, and the light controller is circular or polygonal about the axis Z, and is cylindrical or conical along the axis Z direction. The peripheral wall has translucency, and the peripheral wall diffuses and transmits the incident light beam in the ridge direction, and travels straight in the circumferential direction around the axis Z without substantially diffusing. And a lens plate that gradually increases the refraction angle of the outgoing light with respect to the incident light from the bottom to the top on the surface of the peripheral wall, and the light generator Thus, the light beam group is irradiated from substantially the horizontal direction.

According to the present invention, since the lens plate that gradually increases the refraction angle of the emitted light with respect to the incident light is arranged on the surface of the peripheral wall from below to above, as an example, the projector can be Even if it is projected, the projected light beam is refracted slightly upward at the lower part of the light beam controller and refracted further upward at the upper part. This is equivalent to irradiating the projector obliquely from below, so that the thickness is not increased and a large mirror is not required.
Furthermore, since the incident angle of the light beam projected from the projector with respect to the side surface of the conical screen can be controlled, the projection system layout can be configured in a direction in which the size in the thickness direction does not increase. Further, when a wedge-shaped optical element is used, a layout in which the projector is not opposed to the screen is possible, and scattered light (unnecessary light) inside the projector can be avoided from being seen from the viewpoint.

It is typical sectional drawing of the three-dimensional display which concerns on one embodiment of this invention. It is a schematic plan view of the three-dimensional display of FIG. FIG. 3 is a perspective view of a light beam controller used in the three-dimensional display of FIGS. 1 and 2. It is a partial expanded sectional view of an example of a light controller. It is a partial expanded sectional view of other examples of a light controller. It is a partial expanded sectional view of further another example of a light beam controller. It is a schematic diagram for demonstrating the other structure of a light controller. It is a schematic diagram for demonstrating another structure of a light beam controller. FIG. 5 is a schematic plan view for explaining the operation of the scanning projector. It is a schematic plan view for demonstrating the presentation method of a stereo image. It is typical sectional drawing for demonstrating the presentation method of a stereo image. It is a schematic plan view for demonstrating the generation | occurrence | production principle of the binocular parallax in the three-dimensional display which concerns on this Embodiment. It is a schematic diagram which shows roughly one Example to which this invention is applied. It is a schematic diagram which shows typically the cross section which cut the lens board in the ridgeline direction. It is a perspective view which shows the state which cut the lens plate into the horizontal direction. It is a figure which shows an example which forms such a conical lens plate. It is a schematic diagram which shows the inclination | tilt angle in each location in a lens plate. It is a schematic diagram which shows the cross section of the state which formed the lens plate in the outer peripheral surface of a surrounding wall, and formed the diffusion optical element in the inner peripheral surface of the surrounding wall. It is a perspective view which shows the edge part in the state which formed the lens plate in the outer peripheral surface of a surrounding wall, and formed the diffusion optical element in the inner peripheral surface of the surrounding wall. It is a top view of a junction part (joint) when a protrusion part is piled up and adhered. It is a schematic diagram showing a state in which chromatic aberration occurs because incident light before correction differs in emission angle depending on the light source color. It is a schematic diagram which shows the state which absorbs chromatic aberration by correction | amendment. It is a schematic diagram which shows the positional relationship which makes the projector in a prior art oppose diagonally from the cone-shaped light controller. It is a schematic diagram which shows the positional relationship in the case of bending a projection optical axis with a mirror.

I. Outline Description of Stereoscopic Display The operation principle of the stereoscopic display is described in detail in Patent Document 1, but will be described below.

(1) Configuration of stereoscopic display FIG. 1 is a schematic cross-sectional view of a stereoscopic display according to an embodiment of the present invention. FIG. 2 is a schematic plan view of the stereoscopic display of FIG. FIG. 3 is a perspective view of a light beam controller used in the stereoscopic display of FIGS. 1 and 2.
As shown in FIG. 1, the stereoscopic display includes a truncated cone-shaped light beam controller 1, a plurality of scanning projectors 2, a control device 3, and a storage device 4.
The three-dimensional display shown in FIGS. 1 and 2 is provided on a table 5. The table 5 includes a top plate 51 and a plurality of legs 52. The top plate 51 has a circular hole.
As shown in FIG. 3, the light beam controller 1 has a truncated cone shape that is rotationally symmetric about the axis Z. The large diameter bottom portion and the small diameter bottom portion of the light beam controller 1 are open. The light beam controller 1 is formed such that an incident light beam diffuses and transmits in the ridge line direction T and passes straight in the circumferential direction R around the axis Z without substantially diffusing. Details of the configuration of the light beam controller 1 will be described later.

As shown in FIG. 1, the light beam controller 1 is fitted into the circular hole of the top plate 51 so that the large-diameter bottom opening faces upward. An observer 10 around the table 5 can observe the inner peripheral surface of the light beam controller 1 from obliquely above the top plate 51 of the table 5.
Below the table 5, a plurality of scanning projectors 2 are arranged on a circumference around the axis Z of the light beam controller 1. The plurality of scanning projectors 2 are provided so as to irradiate the outer peripheral surface of the light beam controller 1 from obliquely below the light beam controller 1.
A transparent circular plate may be fitted into the circular hole portion of the table 51.

  Each scanning projector 2 can emit a light beam and deflect the light beam in a horizontal plane and a vertical plane. Thereby, each scanning projector 2 can scan the outer peripheral surface of the light beam controller 1 with the light beam. Here, the light beam refers to light represented by a straight line that does not diffuse.

  The storage device 4 includes, for example, a hard disk, a memory card, and the like. The storage device 4 stores stereoscopic shape data for presenting the stereoscopic image 300. The control device 3 is composed of a personal computer, for example. The control device 3 controls the plurality of scanning projectors 2 based on the solid shape data stored in the storage device 4. Thereby, the stereoscopic image 300 is presented above the light controller 1. In addition, in order to obtain the observer's viewpoint position 500 more accurately, a configuration including the camera 8 may be employed.

(2) Basic Configuration and Manufacturing Method of Light Controller 1 FIG. 4 is an enlarged sectional view of a part of an example of the light controller 1.
The light beam controller 1 of FIG. 4 has a transparent truncated cone-shaped light beam controller body 11. A plurality of annular lenses 12 are provided on the outer peripheral surface of the light beam controller main body 11 so as to be closely arranged in the ridge line direction T. Each annular lens 12 has a semi-cylindrical vertical cross section. The annular lens 12 may have a semicircular cross section. The dimension of the light beam controller 1 is arbitrary. For example, the diameter of the large diameter bottom portion of the light control body 11 is 200 mm, the diameter of the small diameter bottom portion is 20 mm, and the height is 110 mm.

4 can be produced by applying a cutting blade while rotating a transparent material made of a transparent resin having a certain refractive index, such as acrylic or polycarbonate. Moreover, the light controller 1 can be manufactured by producing a mold having a shape corresponding to the light controller 1 and filling the mold with a transparent resin such as acrylic or polycarbonate. Furthermore, the light control element 1 can also be produced by a three-dimensional modeling method using an ultraviolet curable resin. Moreover, the light control element 1 can be produced by etching the surface of a transparent material having a truncated cone shape. Further, the light controller 1 can be manufactured by laser processing or electric discharge processing of the surface of the transparent material having a truncated cone shape. Moreover, the light control element 1 can be produced by applying an ultraviolet curable resin to the surface of a transparent material having a truncated cone shape and irradiating ultraviolet rays for each annular region having a constant width extending in the circumferential direction.
In the example of FIG. 4, the plurality of annular lenses 12 are formed on the outer peripheral surface of the light controller main body 11, but the plurality of annular lenses 12 may be formed on the inner peripheral surface of the light controller main body 11.

  According to the light beam controller 1 of FIG. 4, the annular lens 12 has a constant thickness in the circumferential direction and has a function of diffusing light beams in the ridge line direction T. Accordingly, when a light beam is applied to the outer peripheral surface of the light beam controller 1 in FIG. 4, the light beam is transmitted while being diffused in the ridge line direction T, and is transmitted in a straight line without being diffused in the circumferential direction.

FIG. 5 is an enlarged sectional view of a part of another example of the light beam controller 1.
In the light beam controller 1 of FIG. 5, a plurality of annular prisms 13 having a polygonal cross section are provided on the outer peripheral surface of the light beam controller body 11 so as to be closely arranged in the ridge line direction T. The cross-sectional shape of the annular prism 13 may be a polygon other than a triangle.
According to the light beam controller 1 of FIG. 5, the annular prism 13 has a constant thickness in the circumferential direction and has a function of diffusing light beams in the ridge line direction T. Accordingly, when a light beam is irradiated on the outer peripheral surface of the light beam controller 1 of FIG. 5, the light beam is transmitted while being diffused in the ridge line direction T, and is transmitted in a straight line without being diffused in the circumferential direction.

FIG. 6 is an enlarged sectional view of a part of still another example of the light beam controller 1.
The light beam controller 1 of FIG. 6 is produced by winding a transparent material 14 having a thread-like refractive index on the outer peripheral surface of a transparent frustoconical light beam controller body 11 in the circumferential direction. The transparent materials 14 are densely arranged in the ridge line direction T. The cross-sectional shape of the transparent material 14 may be a perfect circle or an ellipse. For example, nylon thread can be used as the transparent material 14.
Alternatively, the light control element 1 can also be manufactured by sticking a plurality of thread-like transparent materials in order on the outer peripheral surface of the transparent frustoconical light control element body 11 using a quick-drying adhesive. For example, an ultraviolet curable resin can be used as the adhesive.

  According to the light beam controller 1 of FIG. 6, the transparent material 14 has a constant thickness in the circumferential direction, and has a ball lens function in the ridge line direction T. Thereby, when a light beam is irradiated on the outer peripheral surface of the light beam controller 1, the light beam is transmitted while being diffused in the ridge line direction T, and is transmitted in a straight line without being diffused in the circumferential direction.

FIG. 7 is a schematic diagram for explaining another configuration of the light beam controller 1. FIG. 7A shows a holographic screen 15 that transmits light in the direction X with little diffusion and transmits light in a direction Y orthogonal to the direction X. FIG. 7B shows a triangular sheet 16 formed by cutting the holo screen 15 of FIG. Here, the holographic screen is an optical element that is manufactured by a photographic dry plate technique and that can control the flight direction of incident light rays.
The light beam controller 1 can be formed by sticking the triangular sheet 16 in FIG. 7A to the surface of the transparent circular truncated cone light beam controller body 11. Alternatively, the light controller 1 having a pseudo truncated cone shape can be manufactured by connecting N triangular sheets 16 to form an N truncated cone. Here, N is an integer of 3 or more.

FIG. 8 is a schematic diagram for explaining still another configuration of the light beam controller 1. FIG. 8A shows an optical sheet 17 made of a holographic screen or Fresnel lens having a function of diffusing incident light rays in the radial direction. The Fresnel lens is a sheet-like lens having grooves in the circumferential direction.
As shown in FIG. 8B, the optical sheet 17 is cut into a fan-shaped sheet 18. And as shown in FIG.8 (c), the frustoconical light controller 1 is produced by connecting the edge | side A and the edge | side B of the fan-shaped sheet 18 together.

  In the present embodiment, the light beam controller 1 has a truncated cone shape. However, the present invention is not limited to this. May be. These shapes are called cone shapes.

(3) Operation of Scanning Projector 2 FIG. 9 is a schematic plan view for explaining the operation of the scanning projector 2. FIG. 9 shows only one scanning projector 2.
The scanning projector 2 can emit a light beam composed of laser light and deflect the light beam in a horizontal plane and a vertical plane.
When the scanning projector 2 deflects the light beam in a horizontal plane, the outer peripheral surface of the light beam controller 1 can be scanned in the horizontal direction. Further, the scanning projector 2 deflects the light beam in the vertical plane, whereby the outer peripheral surface of the light beam controller 1 can be scanned in the vertical direction. Thereby, the scanning projector 2 can scan the opposite surface of the light beam controller 1 with the light beam.
Further, the scanning projector 2 can set the color of the light beam for each light beam direction. As a result, the scanning projector 2 emits a light beam group consisting of a plurality of light beams in a pseudo manner.

In FIG. 9, the scanning projector 2 irradiates the light beam controller 1 with a plurality of light beams L1 to L11. The light beams L1 to L11 are set to arbitrary colors, respectively. Thereby, the light rays L1 to L11 of the set colors are transmitted through the plurality of positions P1 to P11 of the light ray controller 1 respectively.
Since the light beam controller 1 transmits the light beams L1 to L11 linearly without diffusing in the circumferential direction, the observer can view only one light beam at a certain position. Moreover, since the light beam controller 1 diffuses and transmits the light beams L1 to L11 in the vertical direction, the observer can visually recognize one light beam from an arbitrary position in the vertical direction.

  In the present embodiment, the scanning projector 2 is used as the light generator, but the present invention is not limited to this. The light generator generally includes a spatial light modulator such as DMD (Digital Mirror Device), LCOS (Liquid Crystal on Silicon) or LCD (Liquid Crystal Display), and a projection system such as a lens array composed of a plurality of lenses. A simple projector can also be used. In this case, when the aperture (aperture) of the projection system is sufficiently small, a light beam group can be formed in the same manner as the scanning projector 2.

(4) Presentation Method of Stereoscopic Image 300 FIG. 10 is a schematic plan view for explaining the presentation method of the stereoscopic image 300. In FIG. 10, three scanning projectors 2A, 2B, and 2C are shown.
For example, when a red pixel is presented at a position PR above the light beam controller 1, a red light beam LA0 is emitted from the scanning projector 2A in a direction passing through the position PR, and passes through the position PR from the scanning projector 2B. A red light beam LB0 is emitted in the direction, and a red light beam LC0 is emitted from the scanning projector 2C in a direction passing the position PR. Thereby, a red pixel serving as a point light source is presented at the intersection of the red light beams LA0, LB0, and LC0. In this case, a red pixel can be seen at the position PR when the observer's eye is at the position IA0, at the position IB0, and at the position IC0.

Similarly, when a green pixel is presented at a position PG above the light beam controller 1, a green light beam LA1 is emitted from the scanning projector 2A in a direction passing through the position PG, and the position PG is output from the scanning projector 2B. A green light beam LB1 is emitted in a direction passing through, and a green light beam LC1 is emitted in a direction passing through the position PG from the scanning projector 2C.
Thereby, a green pixel serving as a point light source is presented at the intersection of the green light beams LA1, LB1, and LC1. In this case, a green pixel is seen at the position PG when the observer's eyes are at the position IA1, the position IB1, and the position IC1.
In this way, light rays of a color to be presented in a direction passing through each position of the stereoscopic image 300 are emitted from each of the plurality of scanning projectors 2A, 2B, 2C.

  A plurality of scanning projectors including the scanning projectors 2A, 2B, and 2C are densely arranged on the circumference, and a space inside the light controller 1 is formed by a group of light beams emitted from the plurality of scanning projectors. If the intersection point group is sufficiently densely filled, an appropriate ray passing through the positions PR and PG will be incident on the eye even if the inside of the ray controller 1 is observed from any direction on the circumference. The human eye recognizes that there is a point light source there. Since the person recognizes the illumination light reflected or diffused on the surface of the real object as an object, the surface of the object can be regarded as a set of point light sources. That is, the three-dimensional image 300 can be presented by appropriately reproducing the color of a certain position PR, PG that is desired to be the surface of the object by the light rays coming from the plurality of projectors 2A, 2B, 2C.

  In this way, the stereoscopic image 300 can be presented in the space inside and above the light beam controller 1. In this case, the observer can visually recognize the same stereoscopic image 300 from different directions at different positions in the circumferential direction.

FIG. 11 is a schematic cross-sectional view for explaining a method for presenting the stereoscopic image 300. In FIG. 11, one scanning projector 2 is shown.
As shown in FIG. 11, the light beam emitted from the scanning projector 2 is diffused in the vertical direction by the light beam controller 1 at the diffusion angle α. Thereby, the observer can see the same color light beam emitted from the scanning projector 2 at different positions in the vertical direction within the range of the diffusion angle α. For example, even when the observer moves the line of sight from the reference position E to the upper position E ′, the same portion of the stereoscopic image 300 can be viewed. In this case, the position of the stereoscopic image 300 visually recognized by the observer is moved to the position of the stereoscopic image 300 ′ by the position of the observer's eyes in the vertical direction. Although not shown, if the observer moves the line of sight downward from the reference position E, the same portion of the stereoscopic image 300 can be viewed as being at a lower position. Thus, since the light emitted from the scanning projector 2 is diffused in the vertical direction by the light controller 1, the stereoscopic image 300 can be observed even if the observer moves the line of sight up and down.

The color of each light beam of the light beam group emitted from the plurality of scanning projectors 2 in FIG. 1 is calculated by the control device 3 based on the solid shape data stored in the storage device 4. Specifically, the control device 3 obtains an intersection between a surface of a three-dimensional solid shape defined in advance as solid shape data and each light ray, and calculates an appropriate color to be given to the light ray.
The control device 3 controls the plurality of scanning projectors 2 based on the calculated color of each light beam in the light beam group. Thereby, a group of light beams each having a set color is emitted from each scanning projector 2 so that the stereoscopic image 300 is presented above the light beam controller 1.
As described above, according to the stereoscopic display according to the present embodiment, the directional display of the stereoscopic image 300 is possible.

(5) Binocular Parallax Generation Principle Here, the binocular parallax generation principle in the stereoscopic display according to the present embodiment will be described.

FIG. 12 is a schematic plan view for explaining the principle of generation of binocular parallax in the stereoscopic display according to the present embodiment. FIG. 12 shows four scanning projectors 2a, 2b, 2c, and 2d.
In FIG. 12, when the observer views the point P31 of the light beam controller 1, the light beam La emitted from the scanning projector 2a is incident on the right eye 100R and emitted from the scanning projector 2b to the left eye 100L. The incident light ray Lb is incident. When the observer sees the point P32 of the light beam controller 1, the light beam Lc emitted from the scanning projector 2c is incident on the right eye 100R, and the light beam emitted from the scanning projector 2d is incident on the left eye 100L. Ld is incident.

Here, the color of the light beam La and the color of the light beam Ld are the same, the color of the light beam Lb is different from the color of the light beam La, and the color of the light beam Lc is different from the color of the light beam Ld. In this case, the color of the point P31 on the light beam controller 1 differs depending on the viewing direction. Further, the color of the point P32 on the light beam controller 1 also varies depending on the viewing direction.
A point Pa of the stereoscopic image 300 is created by the light ray La, a point Pb of the stereoscopic image 300 is created by the light ray Lb, a point Pc of the stereoscopic image 300 is created by the light ray Lc, and a point Pd of the stereoscopic image 300 is created by the light ray Ld. It is done.

  In the example of FIG. 12, the point Pa and the point Pc of the stereoscopic image 300 are at the same position. That is, the points Pa and Pd of the stereoscopic image 300 are created at the intersections of the light beam La and the light beam Ld. The points Pa and Pd can be virtual point light sources. In this case, the direction of viewing the points Pa and Pd with the right eye 100R is different from the direction of viewing the points Pa and Pd with the left eye 100L. That is, there is a convergence angle between the line-of-sight direction of the right eye 100R and the line-of-sight direction of the left eye 100L. Thereby, the stereoscopic view of the image formed by the light beam group becomes possible.

(6) Effect of this Embodiment In the three-dimensional display according to this embodiment, the light beam controller 1 transmits each light beam irradiated by each scanning projector 2 without diffusing in the circumferential direction. Thereby, each intersection of the light beams from the plurality of scanning projectors 2 becomes a point light source. An observer virtually perceives a set of point light sources as a three-dimensional shape of an entity. At this time, as described above, the binocular parallax occurs because the line-of-sight direction of the left eye and the line of sight of the right eye that intersect the same point light source are different. As a result, the stereoscopic image 300 is presented in the space inside and above the light controller 1 by a set of a plurality of point light sources.

  Here, when the observer observes the inner peripheral surface of the light beam controller 1 from above the table 5, each point light source can be seen at the same position from any position around the table 5 at the same height. Therefore, the observer can see the stereoscopic image 300 presented above the light controller 1 from any position around 360 degrees. Therefore, a plurality of persons can observe the stereoscopic image 300 with the naked eye from an arbitrary position without using a special device. Also, the number of observers is not limited.

The light beam controller 1 diffuses and transmits each light beam irradiated by each scanning projector 2 in the ridge line direction. Thereby, even if the height of the observer's viewpoint rises and falls, the observer can see the stereoscopic image 300. Therefore, the viewpoint position of the observer is not limited.
Furthermore, it is not necessary to arrange a device that hinders work in the space above the table 5. Therefore, a work space for performing work using the stereoscopic image 300 presented above the light controller 1 can be secured on the table 5.

II. Detailed Description of Light Controller (Example 1)
(1) Configuration of 3D Display FIG. 1 shows the operation principle of the 3D display, and the projector 2 shows the positional relationship facing the inverted conical light controller 1 from obliquely downward to upward. .
FIG. 13 is a schematic view schematically showing an embodiment to which the present invention is applied. As shown in the figure, the projector 2 is disposed at a position substantially the same height as the light beam controller 1 (screen), and is disposed substantially in the horizontal direction and toward the central direction. Of course, the projection light projected by the projector 2 has a predetermined divergence angle, and the projection range reaches the outer peripheral surface of the light beam control 1 while gradually expanding. Here, on the outside of the peripheral wall of the light beam controller 1, a lens plate (optical element) 6 having the same inverted conical shape as the light beam controller 1 is disposed so as to cover the light beam controller 1 and the outer surface. Details of the lens plate 6 will be described later. In the present embodiment, the lens plate 6 is disposed on the outer side of the peripheral wall, but may be on the inner side.
In this way, since the projector 2 can be disposed on the side of the optical controller 1, the thickness of the apparatus is small, a mirror is unnecessary, and the width can be made compact.
(Example 2)

FIG. 14 is a schematic diagram schematically showing a cross section of the lens plate 6 cut in the ridge line direction. As shown in FIG. 2A, the surface of the cross section has a sawtooth shape or a wedge shape continuous in the vertical direction. Both the saw blade and the wedge shape are formed as an integrated optical element plate, so one side is assimilated with the base material, and the two slant sides alternately alternate, so that the saw blade or wedge with continuous V-shaped projections. Form a shape. The enlarged view (b) shows a triangular wedge shape with one side consisting of an alternate long and short dash line, which is generally a right triangle, but causes a predetermined refraction when the projection light is incident. Are the so-called hypotenuse c and the base a. Further, as shown in FIG. 6A, a refraction angle θk is generated between the incident light and the emitted light on the surface of the peripheral wall due to refraction. The lens plate 6 is formed so that the refraction angle θk of the emitted light with respect to the incident light gradually increases from the lower side to the upper side on the surface of the peripheral wall. That is, the angle between the incident light and the outgoing light at a substantially intermediate height of the lens plate 6 is the refraction angle θk, but the refraction angle θk−α at the slightly lower height, and the slightly higher height. Then, the refraction angle is θk + α. That is, as the surface of the peripheral wall is directed from below to above, the refraction angle is gradually increased from (θk−α) to θk and further to (θk + α).
The size of each wedge is preferably smaller than each pixel of the projected image. That is, in the vertical direction, it is desirable to make the size smaller than one pixel.

  As described above, the lens plate 6 has a property that the refraction angle of the outgoing light with respect to the incident light gradually increases from the lower side to the upper side on the surface of the peripheral wall. If it is assumed that the side of the lens plate 6 on which the oblique side c and the opposite side b are not formed is a straight line as in the case of the alternate long and short dash line, the surface of the peripheral wall gradually approaches the incident light from below to above. In order to change the refraction angle θk of the emitted light so as to increase, it is necessary to make the inclination angle θ of the hypotenuse an angle corresponding to each part of the surface of the peripheral wall.

FIG. 15 is a perspective view showing a state in which the lens plate 6 is cut horizontally. As shown in the figure, the lens plate 6 has a conical shape that covers the conical optical controller 1.
FIG. 16 shows an example in which such a conical lens plate 6 is formed. As shown in FIG. 16A, a material for a fan-shaped lens plate is prepared, and both ends of the fan-shaped lens are brought into contact with each other. By bonding, a conical shape as shown in FIG. In this embodiment, it has a conical shape. However, the present invention is not limited to this, and both the light controller 1 and the lens plate 6 may have a truncated cone shape, or a polygonal truncated cone shape or a polygonal truncated pyramid shape. It may be a so-called cone shape.
When referring to the upper or lower side of the optical controller 1, taking the sector-shaped material shown in FIG. 16 as an example, the lower side (A ′) is the center side of the circular shape that forms the sector, and the upper side (A) is the outer side of the circular shape. On the other side. FIG. 5A shows a cut portion in the ridge line direction by a one-dot chain line.
As shown in FIG. 16, when the rotational symmetry such as a cone is used, the incident conditions of the light rays projected from the projectors 2 on the lens plate 6 are constant with respect to the projectors 2 (light sources) arranged on the circumference. The shape of the lens plate 6 is optimized.

FIG. 17 is a schematic diagram showing the inclination angle θ at each part of the lens plate 6.
As described above, in order to gradually increase the refraction angle of the outgoing light with respect to the incident light from the lower side to the upper side on the surface of the peripheral wall, the inclination angle θ1 of the wedge near the upper side (A) is It is made larger than the inclination angle θ2 of the wedge close to the lower side (A ′). In other words, the inclination of the wedge of the lens plate 6 decreases as it approaches the apex from the bottom of the cone.
Although the specific inclination angle θ varies depending on the wavelength and refractive index of the material of the lens plate 6, the wavelength can be appropriately calculated by computer simulation or the like as long as the material is determined while keeping the wavelength constant for convenience. As an example, assuming an exit angle similar to that shown in FIGS. 23 and 24, the refractive index based on the material of the lens plate 6 is specified after determining the angle of the peripheral wall of the light beam controller 1. The direction of outgoing light at each part is calculated from the lower side to the upper side of the surface of the controller 1 and simulation is performed so that the same outgoing direction can be obtained by a predetermined number of refractions to specify the inclination angle θ.
This is because the angle θ of the projection center axis of the projector 2 with respect to the optical controller 1 (screen and lens plate 6) is 0 <θ = <90 ° on the plane passing through the projection center of the projector 2 and the center axis of the optical control 1. In the range, the inclination of the wedge slope (slope angle θ) is optimized so that the incident angle of 1 on the screen is optimized to the same state as when the original projector 2 was placed directly facing the screen 1. It can be said that it will be decided.
The number of times of refraction changes as appropriate depending on whether the lens plate 6 is a separate body or whether the lens plate 6 is integrated by bonding as described later. That is, if it is a separate body, it is sufficient to consider the refractive index twice. If integrated, it is necessary to consider the refractive index based on the lens shape on the opposite surface in addition to the refractive index of one time. In the case of bonding, the refractive index at the boundary surface with the bonding material is taken into consideration.

(Example 3)
FIG. 18 is a schematic diagram schematically showing a cross section of the light beam controller 1 having a truncated cone shape in a state where the lens plate 6 is formed on the outer peripheral surface of the peripheral wall and the diffusion optical element 1a is formed on the inner peripheral surface of the peripheral wall. It is. As an example, the diffusing optical element 1a corresponds to an annular lens 12 shown in FIG. 4, an annular prism 13 shown in FIG. 5, and a thread-like transparent material 14 shown in FIG. The lens plate 6 and the optical element 1a may be integrally formed through the base material 1b, or three materials may be bonded together, or the lens plate 6 and the optical element 1a may include the base materials 1b and 1b, respectively. As a thing, it is good also as a structure which bonds two sheets together.
Example 4
On the other hand, FIG. (C) is a schematic diagram which shows typically the cross section containing the lens plate 6 concerning a modification. In this example, the saw blade shape or the wedge shape constituting the lens plate 6 is set upside down in the direction opposite to the previous example. In this example, incident light first enters from the side of the base (a in FIG. 14B) and exits from the first hypotenuse (c in FIG. 14B). When the angle at which the projection light is incident on the lens plate 6 is tight, it may not be possible to create a situation in which the refraction angle gradually increases from the bottom to the top on the surface of the peripheral wall only by changing the inclination angle θ of the hypotenuse. . In such a case, it is possible to increase the refraction angle θk of the outgoing light with respect to the incident light by setting the orientation as shown in FIG.
That is, small protrusions having a substantially wedge-shaped cross section having a first hypotenuse, a second hypotenuse, and a base are formed on the surface of the peripheral wall of the lens plate 6 so that the cross section continues in the circumferential direction of the lens plate 6. In this case, the bottom side is arranged on the incident side of the projection light, and the first hypotenuse side is arranged on the emission side. And the inclination angle with respect to the wall surface direction of the peripheral wall at the first hypotenuse gradually increases from the bottom to the top.

(Example 5)
FIG. 19 is a perspective view schematically showing an end portion in a state in which the lens plate 6 is formed on the outer peripheral surface of the peripheral wall and the diffusing optical element 1a is formed on the inner peripheral surface of the peripheral wall. In this embodiment, the lens plate 6 and the diffusing optical element 1a are laminated and adhered. However, in the fan-shaped state as shown in FIG. One of the optical elements 1a has protruding portions H1 and H2 that cannot be bonded to the other. Here, at the protruding portion H1, the end of the diffusing optical element 1a is not laminated with the lens plate 6, and the surface of the base 1b of the optical element 1a is exposed. At the protruding portion H2, the end of the lens plate 6 is exposed. Is not laminated with the diffusing optical element 1a, and the surface of the substrate 1b of the lens plate 6 is exposed. In this way, the portion where one is not bonded to the other forms a stepped step portion, which forms a so-called uneven shape.
By forming a step in the thickness direction and superimposing them, it is possible to reduce reflection at the bonding boundary surface. That is, it is possible to reduce reflection at the boundary surface of the wedge-shaped optical bonding that causes stray light. A transparent adhesive sheet or the like can be used when providing a step in the thickness direction and bonding. Furthermore, assembly can be facilitated by bonding at a step.
Further, the lens plate 6 and the diffusing optical element 1a (screen) are bonded together to form a more compact configuration.

(Example 6)
FIG. 20 is a top view of a joining portion (joint) when the protruding portions H1 and H2 are overlapped and bonded to each other.
When the base materials of the diffusing optical element 1a and the lens plate 6 have the same thickness and the lengths of the protruding portions are made to coincide with each other, the thicknesses of the two portions are overlapped with each other. Joining is possible in a constant state. At this time, if the concave and convex portions are mixed and formed at the respective end portions, both can be fitted to each other.

Thus, according to the present invention, it is possible to provide a light beam controller 1 having the following basic configuration.
The cross section is circular or polygonal about the axis Z, and is cylindrical or cone-shaped along the axis Z direction.
-The peripheral wall has translucency.
In the circumferential wall, the incident light beam diffuses and transmits in the ridge line direction, and passes straight through without being diffused in the circumferential direction centered on the axis Z.
The lens plate has a property that the angle of refraction of outgoing light with respect to incident light gradually increases from the bottom to the top on the surface of the peripheral wall.
According to the present invention, the apparatus can be made compact as described above, and by using the wedge-shaped lens plate 6 (optical element), a layout in which the projector 2 is not opposed to the light beam controller 1 (screen) can be realized. It is also possible to avoid scattering light (unnecessary light) inside the projector from the viewpoint.
(Example 7)
In the above-described embodiment, the basic triangle forming the wedge-shaped cross section is assumed to be a right triangle. That is, the hypotenuse c is formed at an inclination angle θ with respect to the base a, and the opposite side b intersects the base a at a right angle (see FIG. 14B).
As for the opposite side b, as shown in FIG. 14C, it is possible to make it parallel to the incident light from the projector 2. In this case, the opposite side b is not necessarily orthogonal to the bottom side a. Further, since the light beam incident on the light controller 1 from the projector 2 has a slight divergence angle, the incident angle varies depending on the portion (height) of the peripheral wall. Therefore, the opposite side b changes little by little according to the position of the height of the peripheral wall. In such a case, incident light is always projected on the hypotenuse c, so that scattered light does not occur on the opposite side b, and no scattered light occurs on the portion where the hypotenuses c overlap.

(Example 8)
By the way, when the projector 2 forms an image with RGB light sources, when the lens plate 6 generates a refraction angle, the refraction angle varies depending on the color of the light source. Therefore, as a more preferred embodiment, a modification for correcting chromatic aberration will be described.
FIG. 21 is a schematic diagram showing a state in which chromatic aberration occurs because incident light before correction differs in emission angle depending on the light source color. FIG. 22 schematically shows a state in which chromatic aberration is absorbed by correction.
As described above, assuming that light source colors having different wavelengths of RGB are incident on the first hypotenuse on the same optical path as incident light, the arrival point of the light source color of the reference wavelength is P as shown in FIG. In addition, the light source color with a shorter wavelength has a larger refraction angle (reached to the observation point Pn), and the light source color with a longer wavelength has a smaller refraction angle (reached to the observation point Pl). However, as shown in FIG. 22, if a predetermined optical path that takes into account the refraction angle for each light source color is calculated in advance and is incident on the first oblique side of the lens plate 6, the observation point of the reference wavelength can be obtained through each different optical path. Can converge to P. In other words, in this correction method, the flight direction of each wavelength emitted from the lens plate 6 is calculated, the position hitting the screen is calculated, the screen for each color component is rendered and synthesized at the time of projection. .
Specifically, as shown in FIG. 22 (b), when the display position of the reference wavelength (wl1) of the light source of the projector 2 is P, P is the incident angle θi on the slope of the wedge of the light source and the refractive index n of the optical element. (Where n = f2 (wl1)) is a function f1 (θi, n). Therefore, the compensation coefficient K is applied to the display position Px of the wavelength (wl2) other than the reference displayed at the same timing as the display position P of the reference wavelength. That is, Px = f1 (θi · K, n). However, n = f2 (wl2). In this way, means for correcting the position of Px is provided so that the positions of P and Px overlap.

This chromatic aberration correcting means corrects the color shift of the display position caused by the difference in the refraction angle for each wavelength when the light beam projected from the projector 2 which is a light beam generator passes through the lens plate 6 and is refracted. The display position of the reference wavelength (for example, the wavelength of the light source color G) of the projector 2 (light generator) is a function having the incident angle on the inclined surface of the lens plate 6 and the refractive index of the material of the lens plate 6 as variables. As shown, the display position is obtained by multiplying the display position of the wavelength other than the reference (the wavelength of the light source color R and the wavelength of the light source color B) displayed at the same timing as the display position of the reference wavelength (G). Correct so that they overlap. More specifically, after the projection image is decomposed into RGB images, the R image and the B image are deformed with respect to the G image in consideration of a change in the refraction angle. When the deformed R image and B image are projected onto the lens plate 6, the color shift is eliminated at the observation point P because it is projected at a position shifted in consideration of the difference in refraction angle. In the case of each of the RGB screens, generally, an image with a wavelength with a large refractive index is moved slightly downward with respect to an image with a reference wavelength, and an image with a wavelength with a small refractive index is moved slightly upward. Even if the image with the higher refractive index is projected to the lower eye, it will be emitted upward, and the image with the lower refractive index will be emitted upward even if it is applied to the upper eye. Instead, it will be located below. As a result, the three images overlap at the same position at the observation point. Of course, since the lens plate 6 is formed so that the angle of refraction changes as the incident angle changes, not only shifting in the vertical direction, but also processing for adding enlargement or compression in the vertical direction depending on the vertical part of the image. May also be required.
Note that a method for eliminating color misregistration due to a difference in refractive index by correcting each image for each light source color in this manner can also be applied to other projection methods.
As described above, in general, the light source is an RGB monochromatic light source, and the incidence on the slope of the wedge of each wavelength can be made only from the same direction, and the refraction angle differs depending on the wavelength, so that chromatic aberration occurs. However, chromatic aberration can be eliminated by correcting as described above.

III. Other Embodiments In the above-described embodiment, the light beam controller 1 is fixed to the top plate 51 of the table 5, but the light beam controller 1 is rotated around the axis Z by using a rotation driving device such as a motor. You may let them. For example, when the light controller 1 is made of an N cone (N is an integer of 3 or more) or is manufactured by bonding a plurality of sheets, the optical performance at the joint of the light controller 1 is disturbed. Arise. In such a case, the optical performance disturbance at the joint is averaged by rotating the light controller 1 around the axis Z. As a result, unevenness in the image quality of the presented stereoscopic image 300 is prevented.

The light beam controller 1 may have a columnar shape including a cylinder, an elliptical cylinder, or an N prism (N is an integer of 3 or more). Also in this case, the light controller 1 transmits the light while diffusing the light in the vertical direction. Thereby, the stereoscopic image can be presented so that at least a part thereof is positioned in a space on a reference surface such as the upper surface of the top plate 51 of the table 5.
Needless to say, the present invention is not limited to the above embodiments. It goes without saying for those skilled in the art,

・ Applying mutually interchangeable members and configurations disclosed in the above embodiments by appropriately changing the combination thereof.− Although not disclosed in the above embodiments, it is a publicly known technique and the above embodiments. The members and configurations that can be mutually replaced with the members and configurations disclosed in the above are appropriately replaced, and the combination is changed and applied. It is an embodiment of the present invention that a person skilled in the art can appropriately replace the members and configurations that can be assumed as substitutes for the members and configurations disclosed in the above-described embodiments, and change the combinations and apply them. It is disclosed as.

DESCRIPTION OF SYMBOLS 1 ... Light controller, 2, 2A, 2B, 2C, 2a, 2b, 2c, 2d ... Scanning projector, 3 ... Control device, 4 ... Memory | storage device, 5 ... Table, 10 ... Observer, 11 ... Light controller Main body, 12 ... annular lens, 13 ... annular prism, 14 ... transparent material, 15 ... holoscreen, 16 ... triangular sheet, 17 ... optical sheet, 18 ... fan-shaped sheet, 51 ... top plate, 52 ... leg, 300 ... stereoscopic image , H1, H2 ... protruding part.

Claims (10)

The cross-section is circular or polygonal about the axis Z, and is cylindrical or cone-shaped along the axis Z direction. The peripheral wall has translucency, and the incident light is incident on the ridge line. A light control element formed so as to be diffused and transmitted, and to be transmitted in a straight line without substantially diffusing in the circumferential direction around the axis Z,
A light beam controller comprising a lens plate that gradually increases the refraction angle of outgoing light with respect to incident light from below to above on the surface of the peripheral wall.   The lens plate is formed with small wedge-shaped protrusions having a first oblique side and a second oblique side on the surface of the peripheral wall so that the same cross section is continuous in the circumferential direction of the lens plate. The light beam controller according to claim 1, wherein an inclination angle of the first oblique side with respect to a wall surface direction of the peripheral wall gradually increases from the lower side toward the upper side.   The light control element according to claim 1, wherein the lens plate is formed on an outer surface of the peripheral wall.   The light control element according to claim 1, wherein the lens plate is formed on an inner surface of the peripheral wall.   The light beam controller has a concave and convex shape corresponding to each other in the thickness direction at the joint end portion of the peripheral wall, and the convex portions are fitted in the concave portions, so that the thickness is constant. The light beam controller according to claim 1, wherein the light beam controller is bonded.   The light control element is a diffusing optical device in which the incident light beam diffuses and transmits in the ridge line direction and passes straightly without being diffused in the circumferential direction around the axis Z. The light control element according to claim 5, wherein the light control element is formed by stacking elements.   The lens plate and the diffusing optical element are laminated and adhered, and at the joint end portion, one of the lens plate and the diffusing optical element has a protruding portion that cannot be bonded to the other, and the protruding portion The light control element according to claim 6, wherein the concave and convex shapes are configured so that the convex portions can be fitted into the concave portions and the thickness is fixed. A stereoscopic display for presenting a stereoscopic image based on stereoscopic shape data so that at least a part thereof is located in a space on a predetermined reference plane,
A light controller arranged to have an opening on the reference surface and a peripheral wall below the reference surface;
The light beam controller is disposed around the light beam controller so as to irradiate the outer peripheral surface of the peripheral wall of the light beam controller with a light beam group composed of a plurality of light beams below the reference surface and from the outside of the light beam controller. A plurality of light generators;
Control means for controlling the plurality of light generators so that a three-dimensional image is presented by a group of light beams generated by the plurality of light generators based on the three-dimensional shape data;
The control means controls the plurality of light generators so that at least a part of a stereoscopic image is presented above the opening of the light controller.
The light controller is
The cross-section is circular or polygonal about the axis Z, and is cylindrical or cone-shaped along the axis Z direction. The peripheral wall has translucency, and the incident light is incident on the ridge line. Is diffused and transmitted, and in the circumferential direction centered on the axis Z, it is formed so as to pass straight through without substantially diffusing, and
A lens plate in which the refraction angle of the outgoing light with respect to the incident light gradually increases from the bottom to the top on the surface of the peripheral wall;
The three-dimensional display, wherein the light generator irradiates the light beam controller from a substantially horizontal direction.   The chromatic aberration correction means for correcting a color shift of a display position caused by a difference in a refraction angle for each wavelength when a light beam projected from the light beam generator passes through the lens plate and is refracted. The three-dimensional display according to 8.   The chromatic aberration correcting means displays the reference wavelength on the assumption that the display position of the reference wavelength of the light generator is expressed by a function having an incident angle on the inclined surface of the lens plate and a refractive index of the material of the lens plate as variables. The three-dimensional display according to claim 9, wherein the display position is corrected so as to overlap by applying a correction coefficient to the display position of a wavelength other than the reference displayed at the same timing as the position.

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