Image display apparatus

Abstract

An image display device (100) includes an irradiation target (12), a rotation mechanism (14), an emission unit (11), an optical unit (13), and a control unit. The irradiation target (12) is arranged at least partially around a specific axis (O) and irradiated by the image light, and has at least one angle controller that emits the image light at mutually different emission angles for each region and / or each position where the image light is incident. The rotation mechanism (14) rotates the irradiation target (12) about a specific axis (O). The emission unit (11) emits the image light along the specific axis (O), and is capable of switching the image light at least at an interval shorter than the rotation period of the rotation mechanism (14). The optical unit (13) is disposed facing the emission unit (11) with a specific axis (O) as a reference, and controls the incidence angle of the image light emitted by the emission unit (11) with respect to the irradiation target (12). The control unit synchronizes the display of an image comprising the image light with the rotation of the irradiation target (12).

Description

Technical Field

[0001] The present technical content relates to an image display device capable of performing stereoscopic display that can be viewed with naked eyes. Background Art

[0002] Conventionally, there is a technology that can perform stereoscopic display by displaying a viewpoint image for each viewpoint of a viewer viewing a screen. For example, Patent Document 1 discloses a display device that displays a stereoscopic image by rotating a flat screen. The display device includes an annular polyhedral reflector arranged below the flat screen around a rotation axis. The image segments are projected onto the polyhedral reflector by a projector. The projected image segments are reflected by the polyhedral reflector to be displayed on the rotating screen. As a result, a stereoscopic image is formed in which different sides of the stereoscopic image can be seen at different viewpoints (for example, paragraphs

[0024] and

[0025] of the specification in Patent Document 1 and FIG. 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2006-010852 Summary of the invention

[0006] Technical problems to be solved by this technical content

[0007] When stereoscopic display is performed by rotating a flat-panel screen using the method described above, the transmittance near the rotation axis of the screen may decrease, and thus the image quality may be reduced. In addition, a rotation mechanism located at the center needs to be provided. Therefore, for example, the projection distance to the projector becomes larger, and this makes the size of the device larger.

[0008] In view of the above circumstances, an object of the present technical content is to provide a small image display device that can perform high-quality stereoscopic display.

[0009] Means of solving the problem

[0010] In order to achieve the above-mentioned object, an image display device according to one embodiment of the present technology includes an irradiation target, a rotation mechanism, an emission section, an optical section, and a control section.

[0011] The illumination target is at least partially arranged around a specific axis, and the image light is irradiated on the illumination target, and the illumination target includes at least one angle controller, which emits the image light at different emission angles for each area and / or each position where the image light is incident.

[0012] The rotating mechanism rotates the irradiation target around the specific axis.

[0013] The emitting section emits the image light along the specific axis, and the emitting section is capable of switching between the image lights at least at intervals shorter than a rotation cycle performed by a rotation mechanism.

[0014] The optical section is arranged facing the emitting section with the specific axis as a reference, and the optical section controls an incident angle at which the image light emitted by the emitting section is incident on the irradiation target.

[0015] The control section synchronizes display of an image formed by the image light with rotation of the irradiation target.

[0016] In the image display device, image light emitted by an emitting portion along a specific axis is incident on an irradiation target through an optical portion, the irradiation target is at least partially arranged around the specific axis, and the irradiation target rotates around the specific axis. The irradiation target is provided with an angle controller, which emits image light at different emission angles for each area and / or each position where the image light is incident on the irradiation target. The image display composed of the image light is synchronized with the rotation of the irradiation target. The image light is appropriately switched to emit individual image lights. In this way, an image displayed to each viewpoint is generated. Therefore, the central part having the specific axis is hollow, and a small-sized image display device can perform high-quality stereoscopic display. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 schematically shows a configuration example of an image display device according to a first embodiment of the present technology.

[0018] FIG. 2 schematically shows the characteristics of the emission angle set for the screen.

[0019] FIG. 3 schematically shows the characteristics of the diffusion angle performed by the screen.

[0020] FIG. 4 is a block diagram showing an example of a functional configuration of an image display device.

[0021] FIG5 schematically shows an example of image data.

[0022] FIG. 6 is a schematic diagram for describing an overview of a stereoscopic display operation performed by the image display device.

[0023] FIG. 7 schematically shows an operation example of an angle controller for displaying viewpoint images.

[0024] FIG. 8 schematically shows an example of the operation of the segmented area included in the angle controller.

[0025] FIG. 9 schematically shows a configuration example of segmented areas.

[0026] FIG. 10 is a schematic diagram for describing the relationship between the segmented areas and the crosstalk.

[0027] FIG. 11 schematically shows an example of performing image display on a transparent screen including a segmented area and a non-diffusion area.

[0028] FIG. 12 schematically shows an example of display control performed using the screen including the segmented area and the non-diffusion area shown in FIG. 11 .

[0029] FIG. 13 schematically shows an example in which image display is performed using viewpoint images including a display area and a non-display area.

[0030] FIG. 14 schematically shows an example of display control using the viewpoint images including the display area and the non-display area shown in FIG. 13 .

[0031] FIG. 15 schematically shows an example of performing image display using a screen including a segmentation area and a non-diffusion area and a viewpoint image including a display area and a non-display area.

[0032] FIG. 16A schematically shows an example in which image display is performed using a screen in which divided areas are formed without a gap.

[0033] FIG. 16B schematically shows an example of performing image display using a screen in which the emission angle continuously changes.

[0034] FIG. 17 is a schematic diagram for describing a method for adjusting the position of a black stripe region.

[0035] FIG. 18 schematically shows a configuration example of the cover portion.

[0036] FIG19 schematically shows an arrangement example of reflecting mirrors.

[0037] FIG. 20 schematically shows a configuration example of a cross section of a screen and a cover portion.

[0038] FIG. 21 schematically shows a configuration example of a rotating mechanism.

[0039] FIG. 22 schematically shows a configuration example of a rotational shake suppression mechanism.

[0040] FIG. 23 schematically shows a configuration example of a rotational shake suppression mechanism.

[0041] FIG. 24 schematically shows a configuration example of a reflection suppressing member.

[0042] FIG25 schematically shows a configuration example of a transmitting section.

[0043] FIG. 26 schematically shows a configuration example of an image display device according to the second embodiment.

[0044] FIG. 27 schematically shows a configuration example of a screen according to the third embodiment.

[0045] FIG. 28 is a schematic diagram for describing a method for adjusting the position of a black stripe area on a screen provided with a plurality of angle controllers.

[0046] FIG. 29 schematically shows a configuration example of a screen for color display according to the fourth embodiment.

[0047] FIG30 schematically shows another configuration example of a screen for color display.

[0048] FIG. 31 schematically shows a configuration example of a transmitting section and a configuration example of image data according to another embodiment.

[0049] FIG. 32 schematically shows a configuration example of a screen according to other embodiments.

[0050] FIG. 33 is a schematic diagram for describing a method of displaying viewpoint images using a divergent screen.

[0051] FIG. 34 schematically shows an example of using a physical slit to adjust the diffusion angle.

[0052] FIG. 35 schematically shows an example of segmented regions having different angular components in the vertical direction.

[0053] FIG. 36 schematically shows another example of a screen in which the emission angle is changed in the up-down direction.

[0054] FIG. 37 is a schematic diagram for describing how viewpoint images are presented according to changes in the up and down positions of the viewpoints.

[0055] FIG. 38 is a perspective view showing a configuration example of an image display device.

[0056] FIG39 is a plan view of the image display device shown in FIG38.

[0057] FIG. 40 is a bottom view of the image display device shown in FIG. 38 .

[0058] FIG. 41 is a side view of the image display device shown in FIG. 38 .

[0059] FIG. 42 is a perspective view of a screen unit provided in the image display apparatus shown in FIG. 38 .

[0060] FIG43 is a plan view of the screen unit shown in FIG42.

[0061] FIG. 44 is a side view of the screen unit shown in FIG. 42 .

[0062] FIG. 45 is a perspective view showing another configuration example of the screen unit.

[0063] FIG46 is a plan view of the screen unit shown in FIG45 .

[0064] FIG. 47 is a bottom view of the screen unit shown in FIG. 45 .

[0065] FIG48 is a side view of the screen unit shown in FIG45 .

[0066] FIG. 49 is a perspective view showing another configuration example of the screen unit.

[0067] FIG50 is a plan view of the screen unit shown in FIG49.

[0068] FIG51 is a bottom view of the screen unit shown in FIG49.

[0069] FIG52 is a side view of the screen unit shown in FIG49.

[0070] FIG. 53 is a perspective view showing another configuration example of the image display device.

[0071] FIG54 is a plan view of the image display device shown in FIG53.

[0072] FIG. 55 is a bottom view of the image display device shown in FIG. 53 .

[0073] FIG56 is a side view of the image display device shown in FIG53.

[0074] FIG57 is a perspective view of a screen unit provided in the image display device shown in FIG53.

[0075] FIG58 is a plan view of the screen unit shown in FIG57 .

[0076] FIG59 is a side view of the screen unit shown in FIG57 . DETAILED DESCRIPTION

[0077] Embodiments of the present technology will be described below with reference to the drawings.

[0078] <First Embodiment>

[0079] [Configuration of image display device]

[0080] Fig. 1 schematically shows a configuration example of an image display device according to a first embodiment of the present technology. Fig. 1A is a perspective view showing the appearance of an image display device 100. Fig. 1B is a schematic cross-sectional view showing the configuration of the image display device 100.

[0081] In the description of this embodiment, the direction of the plane (XY plane) in which the image display device 100 is arranged is referred to as the horizontal direction, and the direction perpendicular to the horizontal direction (Z direction) is referred to as the up-down direction. Of course, the present technical content can be applied regardless of the direction in which the image display device 100 is arranged.

[0082] The image display apparatus 100 includes a base 10 , a transmitting portion 11 , a screen 12 , a reflecting mirror 13 , a rotating mechanism 14 , a cover portion 15 , and a controller 19 (not shown) (refer to FIG. 4 ).

[0083] In the image display device 100 , the image light 1 emitted by the emission section 11 is incident on the screen 12 through the reflection mirror 13 , wherein the screen 12 is rotated by the rotation mechanism 14 .

[0084] The screen 12 is configured to emit incident image light 1 at different emission angles for each area where the image light 1 is incident on the screen 12 (or for each position where the image light 1 is incident on the screen 12). In addition, in the image display device 100, the controller 19 synchronizes the display of an image composed of the image light 1 with the rotation of the screen 12. Such a configuration can display an image so that the image is directed toward each viewpoint, respectively. The configuration of the screen 12 and the operation of the controller 19 will be described later.

[0085] The image display device 100 is a device that displays a viewpoint image for each viewpoint to perform stereoscopic display. Fig. 1 schematically shows a cubic image as an example of a stereoscopic display formed of viewpoint images.

[0086] The configuration of each structural element of the image display device 100 is described in detail below.

[0087] The base 10 is provided at the lower part of the image display device 100. The base 10 holds the transmitting portion 11, the rotating mechanism 14, and the cover portion 15 using any holding mechanism (not shown). In addition, as necessary, a power source (not shown) such as a battery, a speaker, elements required for operating the image display device 100, and the like are provided on the base 10. The base 10 in the form of a cylinder is used in FIG. The shape of the base 10 and the like are not limited, and any shape, such as a rectangular parallelepiped form, may be used.

[0088] The emitting portion 11 is in the form of a cylinder and is arranged upward in a substantially central portion of the base 10. The emitting portion 11 emits image light 1 constituting an image along an optical axis extending parallel to the up-down direction (Z direction). In the present embodiment, the optical axis O corresponds to a specific axis.

[0089] B in FIG. 1 shows a cross section of the image display device 100 taken along a direction parallel to an arbitrary plane including the optical axis O. The emitting portion 11 radially emits the image light 1 along the optical axis O. Therefore, as shown in B in FIG. 1 , the emitting portion 11 emits the image light 1 within a specific viewing angle range in an arbitrary plane including the optical axis O. B in FIG. 1 schematically shows an inner optical path close to the optical axis O and an outer optical path far from the optical axis O as examples of optical paths through which the image light 1 passes.

[0090] The emitting section 11 can switch between the image lights 1 at intervals shorter than at least the rotation cycle performed by the rotating mechanism 14. In other words, the emitting section 11 can switch the image at least once within one rotation of the screen 12. Typically, the image light 1 (image) is switched tens to hundreds of times within one rotation of the screen 12. As described above, the screen 12 is a high-speed projector that switches between images at a high frame rate.

[0091] For example, a projection device (projector) having a light emitting element using a laser diode (LD), a light emitting diode (LED), or a fluorescent light source and a light modulator using a digital micromirror device (DMD) is used as the transmitting section 11. In other words, a projector including a combination of an LD and a DMD, a combination of an LED and a DMD, or a combination of a fluorescent light source and a DMD is used. Using a DMD makes it possible to achieve a high frame rate.

[0092] Furthermore, a self-luminous panel including, for example, an organic LED (OLED), μLED, or a vertical cavity surface emitting laser (VCSEL) array may be used as the emitting portion 11. In this case, a projection optical system for projecting the image light 1 is provided.

[0093] The emission section 11 may be configured to emit image light 1 of one color, or to emit a plurality of image lights 1 each corresponding to red, green, and blue.

[0094] In the present embodiment, an example in which the emission section 11 emits one color of image light 1 is mainly described. Furthermore, it is assumed that the emission section 11 includes a single DMD.

[0095] Note that multiple DMDs may be used to form the emitting section 11. When the image light 1 is one color, using, for example, three DMDs can reduce the frame rate required for each DMD to 1 / 3 compared to when a single DMD is used. As described above, using multiple DMDs can reduce the burden imposed on each DMD.

[0096] In addition, any projector capable of switching images at a desired frame rate may be used. For example, a projector including a light modulator using a microelectromechanical system (MEMS), a reflective liquid crystal, a transmissive liquid crystal, or the like may be used.

[0097] In addition, the transmitting unit 11 includes various optical elements.

[0098] For example, a projection lens is provided as the projection optical system. The projection lens is, for example, a lens group including an aspherical lens, and controls the angle of projection light (image light 1) emitted along the optical axis O. An appropriate configuration of the projection lens can also focus light onto the entire surface of the screen 12 by a reflector 13 described later.

[0099] In addition, the emitting section 11 may be provided with a polarizing element for controlling the polarization of the image light 1. An element that performs, for example, linear polarization, radial polarization, or azimuthal polarization is used as the polarizing element. For example, when the polarization direction of the light incident on the screen is appropriately controlled, this makes it possible to reduce the reflectivity of the surface of the screen 12 and increase the brightness.

[0100] In addition, the emitting unit 11 may be provided with an element such as a narrow band pass filter for controlling the wavelength width of the spectrum of the image light 1. As described below, the HOE included in the screen 12 is an optical element with a high wavelength correlation. For example, when the wavelength width of the spectrum of the image light 1 is made smaller than the wavelength width of the diffraction spectrum of the HOE, most of the light can be diffracted by the HOE, thereby improving the light use efficiency of the HOE.

[0101] The screen 12 is arranged completely around the optical axis O. In addition, the screen 12 is in the form of a cylinder. In the present embodiment, the screen 12 is arranged so that the central axis of the (cylindrical) screen 12 and the optical axis O of the emitting portion 11 substantially coincide. The diameter, height, etc. of the screen 12 can be appropriately set. In the present embodiment, the screen 12 corresponds to the irradiation target.

[0102] The screen 12 is a member obtained by providing an optical function to a transparent substrate in the form of a cylinder, for example. Here, an example in which both the inner and outer peripheral surfaces of the screen 12 (transparent substrate) are cylindrical surfaces is mainly described. In this case, neither the inner nor the outer peripheral surface of the screen 12 is tapered. In this way, the screen 12 having an excellent design can be obtained.

[0103] Note that a taper for pulling out can be formed at least in the inner peripheral surface or the outer peripheral surface of the screen 12. The taper for pulling out is a taper for pulling out the injection-molded transparent base member from the mold. The angle of the taper for pulling out is set to, for example, 0.1 to 3 degrees. In this case, large-scale production can be carried out by injection molding. This can reduce the cost of the equipment.

[0104] Typically, a holographic optical element (HOE) is used to form the screen 12. In other words, the screen 12 is a screen using a holographic optical element (HOE).

[0105] HOE is an optical element that diffracts light using interference fringes. Here, a volume HOE in which interference fringes are recorded in a material included in the HOE is used. In addition, for example, a photopolymer (photosensitive material, etc.) or a UV curable resin can be used as a material for recording interference fringes. When interference fringes are appropriately recorded in such a material, an HOE having a desired optical function can be formed.

[0106] The screen 12 is formed of, for example, an optical film bonded to a transparent cylindrical substrate, in which the HOE is formed. In this case, a bonded portion of the optical film is formed in the screen 12. As described later, the screen 12 rotates. Therefore, the audience hardly feels discomfort with the bonded portion. The scheme of bonding the optical film can reduce the manufacturing cost of the screen 12.

[0107] In addition, the screen 12 can be formed by applying a resin to a transparent cylindrical substrate, wherein the HOE is formed in the resin. In this case, the screen 12 without an adhesive portion can be obtained, and high transparency can be exhibited even in a state where the screen 12 is not rotated, for example.

[0108] Note that, in B of Fig. 1, the structure of the screen 12 and the cover portion 15 in the thickness direction thereof is simplified. The structure thereof will be described in detail later with reference to, for example, Fig. 20.

[0109] When forming an HOE, for example, reference light and object light are incident from two directions, and interference fringes generated by the overlap of the reference light and the object light are recorded in a material such as a photopolymer. Thus, an HOE is formed that diffracts light having a wavelength similar to that of the reference light and incident on the HOE at an incident angle similar to that of the reference light, and emits the incident light at an emission angle similar to that of the object light. This can provide an optical function of selectively emitting light having a specific wavelength and incident at a specific incident angle at a specific emission angle.

[0110] Here, the incident angle is an angle of the incident direction of light (eg, the optical path direction of the image light 1 ) relative to the normal direction at the incident point on the surface (eg, the inner surface of the screen 12 ) on which the light is incident.

[0111] In addition, the emission angle is the angle of the emission direction of light relative to the normal direction at the emission point on the surface emitting light (such as the outer surface of the screen 12). Note that in a configuration in which light is diffusely emitted, as described later, the light emission direction with the highest intensity is the emission direction at the emission point.

[0112] Each of the incident angle and the emission angle includes an angle component in a horizontal plane (azimuth component) and an angle component relative to the horizontal plane (elevation component), wherein the XY plane orthogonal to the optical axis O is a horizontal plane. In the present embodiment, the horizontal plane corresponds to an orthogonal plane.

[0113] Note that light incident on the HOE at an angle other than the specific incident angle passes through the HOE without being diffracted by interference fringes. As shown in FIG. 1 , light incident on the inside of the screen 12 at a specific angle from obliquely above is selectively diffracted, and almost all light incident at an angle other than the specific angle passes through the screen 12.

[0114] As described above, the screen 12 has a light-transmitting property. Therefore, the viewer of the image display device 100 can clearly see, for example, the background behind the screen 12 through the screen 12. This can provide, for example, a stereoscopic display superimposed on the background on the screen 12 having high transparency.

[0115] In the present embodiment, the screen 12 is formed using the transmissive HOE 20. The transmissive HOE 20 is an HOE that diffracts light incident on one surface and emits the light from the other surface.

[0116] In the present embodiment, as described below, a plurality of divided areas 23 (refer to FIG. 2 ) each having a different emission angle are formed in the transmissive HOE 20. Therefore, the screen 12 becomes a light control HOE screen that controls the emission angle of the image light 1. In addition, the transmissive HOE 20 records therein interference fringes generated by, for example, light diffused by a diffuser plate, and diffuses the incident image light 1. These interference fringes are recorded in one transmissive HOE 20.

[0117] Note that the screen 12 may be formed by laminating the transmissive HOE 20 having a diffusion function on the outer side of the transmissive HOE 20 in which the segmented regions 23 are formed.

[0118] The transmissive HOE 20 may be simply referred to as the screen 12 hereinafter.

[0119] The method for providing the optical function of the screen 12 is not limited. For example, a diffractive optical element (DOE) different from the HOE may be used. For example, the screen 12 may be formed using a DOE including an embossed hologram element that forms interference fringes using an uneven material surface. In addition, the screen 12 may be formed using an optical element such as a microlens or a Fresnel lens film that can refract light. In addition, a screen 12 that diffuses light by a diffuser such as fine particles may also be used.

[0120] The reflector 13 includes a reflective surface 16 by which the image light 1 emitted by the emitting portion 11 is reflected. The reflector 13 is arranged facing the emitting portion 11 with the optical axis O as a reference so that the reflective surface 16 faces the emitting portion 11.

[0121] The image light 1 emitted by the emission section 11 and incident on the reflection surface 16 is reflected by the reflection mirror 13 toward the screen 12 .

[0122] In the present embodiment, the reflector 13 is fixed to the upper end of the cover 15 arranged around the screen 12, as shown in Fig. 1. Note that the reflector 13 may also be fixed to the screen 12.

[0123] In the present embodiment, the reflecting surface 16 is rotationally symmetric about the optical axis O. For example, the reflecting surface 16 includes a rotation surface obtained by rotating a curve that is a part of a parabola around the optical axis O. The rotation surface is configured so that the side corresponding to the downward curved portion of the parabola (the side of the focus of the parabola) is the side (reflecting surface 16) where light is reflected, and so that the axis of the parabola is different from the optical axis O.

[0124] In the present embodiment, the reflecting surface 16 includes a vertex on the optical axis O. In other words, when viewed from the emitting portion 11, the reflecting surface 16 is curved outward at a point where the rotation plane intersects the optical axis O. In addition, in the cross section of the reflector 13, the left curve and the right curve located on both sides of the optical axis O form a parabola curved toward the emitting portion 11.

[0125] Note that the reflecting mirror 13 may be configured so that the central portion (the tip portion of the mirror) of the reflecting mirror 13 is flat. This makes it possible to make the tip portion of the reflecting mirror 13 invisible from the outside of the device.

[0126] The specific configuration of the reflector 13 is not limited. For example, any material may be used as the material of the reflector 13, such as a resin including acrylic, glass, or metal. For example, mirror finishing is performed on the surface of such a material so that the roughness Ra on the surface is less than about 0.1 μm. Thus, the reflector 13 is formed. In addition, any material may be used for the reflector 13 according to, for example, processing accuracy or productivity.

[0127] In addition, for example, a high reflectivity coating may be applied to the reflective surface 16 of the reflector 13 using, for example, an aluminum or silver thin film. This enables the image light 1 incident on the reflective surface 16 to be efficiently reflected away from the reflective surface 16. In addition, for example, a protective coating for protecting the reflective surface 16 may be applied to the surface of the reflective surface 16 using a thin film such as a SiO2 film or a polymer film, if necessary. In addition, materials such as the high reflectivity coating and the protective coating are not limited.

[0128] In the present embodiment, the reflection mirror 13 functions as an optical section that controls the incident angle of the image light 1 emitted by the emission section 11 onto the screen 12. Specifically, the reflection mirror 13 performs control so that the incident angle of the image light 1 onto the screen 12 is substantially constant.

[0129] For example, the image light 1 radially emitted upward by the emission portion 11 is radially reflected from the reflection surface 16 of the reflector 13 toward the entire periphery of the screen 12. As described above, the reflection surface 16 includes a parabolic rotation surface. Therefore, the image light 1 reflected off the reflection surface 16 is incident on the screen 12 at a substantially constant incident angle, as shown in B of FIG. 1. For example, in a cross section including the optical axis O, the image light 1 reflected off each of the left reflection surface 16 and the right reflection surface 16 located on both sides of the optical axis O is emitted toward the screen 12 in the form of substantially parallel light, as shown in B of FIG. 1.

[0130] As described above, the screen 12 selectively diffracts light incident at a specific incident angle. The image light 1 reflected off the reflector 13 is incident on the screen 12 at this incident angle. This enables the image light 1 to be incident on the entire surface of the screen 12. This can improve the efficiency of diffraction performed on the entire surface of the screen 12, thereby performing image display brightly.

[0131] As described above, the reflection mirror 13 can be said to be an angle control mirror that controls the incident angle of the image light 1 incident on the screen 12 .

[0132] The incident angle on the screen 12 is set to be, for example, within a range between 30 degrees (inclusive) and 85 degrees (inclusive). When the incident angle is 30° or more and smaller, the display range in the height direction is smaller. This makes it possible to use, for example, a screen 12 with a large diameter (small height) or a screen 12 that is slender in the circumferential direction.

[0133] Furthermore, when the incident angle is greater than, for example, 85 degrees, the image light 1 is reflected by the screen 12, and this causes the use efficiency of the light to decrease rapidly. Therefore, the use efficiency of the image light 1 can be prevented from decreasing by setting the incident angle to 85 degrees or less.

[0134] In addition, the configuration of the reflector 13 is not limited. For example, the reflective surface is rotationally symmetrical, as shown in FIG1. ​​This allows full 360-degree circular display. In addition, stereoscopic display can also be performed by limiting the range in the circumferential direction by a portion of the rotationally symmetrical shape.

[0135] The rotating mechanism 14 is connected to the screen 12 and rotates the screen 12 around the optical axis O. FIG1 schematically shows a cylindrical rotating mechanism 17 used as the rotating mechanism 14. The rotating mechanism 17 is a member arranged so that the optical axis O is the central axis of the rotating mechanism 17 and rotates around the optical axis O. The lower end of the screen 12 is fixed to the rotating mechanism 17. The image light 1 emitted by the emitting section 11 passes through the opening of the rotating mechanism 17 to be incident on the reflecting mirror 13.

[0136] The rotating mechanism 17 is, for example, a cylindrical member and is mounted to the base 10 so as to be rotated by a driving unit (not shown) such as a motor. For example, the outer diameter of the rotating mechanism 17 is set to a size similar to the diameter of the screen 12, and the inner diameter of the rotating mechanism 17 is set to a size that does not block the image light 1.

[0137] In the present embodiment, as shown in FIG1 , the transmitting unit 11 and the rotating mechanism 14 are arranged on the same side when viewed from the screen 12. Here, the transmitting unit 11 and the rotating mechanism 14 are arranged together below the screen 12, and this can simplify the configuration of the components located above the screen 12. For example, compared with when the transmitting unit 11 and the rotating mechanism 14 are arranged on both sides of the screen 12, this can make the size of the device smaller.

[0138] The cover 15 is a cover for protecting the rotating screen 12. The cover 15 is arranged to surround the screen, and is formed with a member having a light-transmitting property. In the example shown in FIG. 1 , a cylindrical cover 15 is used. The inner diameter of the cover 15 is set to a size larger than the diameter of the screen 12. The lower end of the cover 15 is fixed to the base 10 so that the optical axis O is the central axis of the cover 15, and the cover 15 surrounds the entire circumference of the screen 12. In addition, the above-mentioned reflector 13 is fixed to the upper end of the cover 15.

[0139] By providing the cover portion 15, the safety and soundproofing properties of the device can be improved.

[0140] The controller 19 synchronizes the display of the image composed of the image light 1 with the rotation of the screen 12. For example, in the image display device 100, each image composed of the image light 1 is switched multiple times within one rotation of the screen 12 to be displayed on the screen 12. The images (videos) in the series of images (videos) displayed here correspond to the rotation angles (rotation positions) of the screen 12, respectively. For example, when the number of times the image is switched within one rotation is N, N images corresponding to the respective rotation angles ωi (i=1, 2, ..., N) are displayed within one rotation of the screen 12. The controller 19 performs synchronization control so that the N images are displayed at appropriate rotation angles, respectively.

[0141] In this embodiment, the controller 19 controls the rotating mechanism 14 to rotate the screen 12, and synchronizes the rotation of the screen 12 with the display of the image formed by the image light 1. As described below, control is performed so that the viewpoint image is correctly displayed toward each of the plurality of viewpoints when the screen 12 is viewed.

[0142] In the present embodiment, the controller 19 corresponds to a control unit.

[0143] [Screen Configuration]

[0144] Fig. 2 schematically shows the characteristics of the emission angle set for the screen 12. A in Fig. 2 is a schematic two-dimensional unfolded view of the cylindrical screen 12. B in Fig. 2 schematically shows the cylindrical screen 12 when viewed in a horizontal plane. C in Fig. 2 schematically shows the rotating screen 12 when viewed in a horizontal plane.

[0145] The following describes the characteristics of the emission angle set for the screen 12.

[0146] As shown in FIG. 2A , the screen 12 includes an angle controller 22 .

[0147] The angle controller 22 is a component provided in the screen 12 to control the emission angle of the image light 1 incident on the screen 12. The angle controller 22 may be formed in a single area on the screen 12, or may be divided to be formed in areas spaced apart from each other on the screen 12. In the present embodiment, an example in which the angle controller 22 is formed in a single area without being divided is mainly described.

[0148] In A of FIG. 2 , a single angle controller 22 is provided at a central portion of the screen 12 in an expanded view.

[0149] The center position of the angle controller 22 in the circumferential direction of the screen 12 (in the left-right direction in the expanded view) is hereinafter referred to as a reference position S of the screen 12 . The reference position S serves as a reference indicating a position on the screen 12 .

[0150] The angle controller 22 emits the image light 1 at different emission angles for each area where the image light 1 is incident. Here, different emission angles mean that the emission angles of the image light 1 incident at the same incident angle are different. Therefore, the angle controller 22 is configured so that the image light 1 incident on each area of ​​the screen 12 at the same incident angle is emitted at different emission angles for each corresponding area. A plurality of areas where different emission angles are set are hereinafter referred to as segmented areas 23.

[0151] For example, when the image light 1 passing through the same optical path is incident on different divided areas 23 on the screen 12 due to the rotation of the screen 12, the image light 1 is emitted at different emission angles. Note that the emission angle does not change in one divided area 23. Therefore, the image light 1 reflected by the reflector 13 to be projected on the screen 12 is divided by a plurality of divided areas 23 and emitted at different emission angles.

[0152] In the present embodiment, the angle controller 22 includes a plurality of division areas 23 which divide the image light 1 incident on the angle controller 22 through the reflection mirror 13 so as to respectively emit the divided image light 1 at different emission angles, as described above.

[0153] For example, images (divided images) divided and displayed by a plurality of divided areas 23 can be combined to display a viewpoint image. In addition, the divided area 23 is a relatively small area. This makes it possible to easily expose high-precision HOE (interference fringes) using a small-sized optical system.

[0154] In the present embodiment, the plurality of divided areas 23 are arranged to extend on the screen 12 in a direction parallel to the optical axis O, as shown in A of FIG. 2 . Here, the vertical direction of the screen 12 (the up-down direction in the expanded view) corresponds to the direction along the optical axis O on the screen 12. Note that the vertical direction is a direction orthogonal to the circumferential direction of the screen 12.

[0155] Each of the plurality of divided regions 23 is a rectangular region extending parallel to the vertical direction of the screen 12. Here, each divided region 23 has a length equal to that of the screen 12 in the vertical direction. However, for example, the divided region 23 may also have a length shorter than that of the screen 12 in the vertical direction.

[0156] In addition, each of the divided regions 23 has an equal length (width) in the circumferential direction. However, the width of the divided regions 23 may be set independently. For example, the divided regions 23 corresponding to the wide azimuth angle in the emission angle of the image light 1 set for the divided regions 23 have a width that appears smaller. In order to correct such an appearance, the divided regions 23 corresponding to the wide emission azimuth angle may be set to have a larger width.

[0157] Furthermore, the method for setting the segmented area 23 is not limited.

[0158] In this embodiment, the emission angles are set for the plurality of segmented areas 23, respectively, so that the emission angles include different angle components formed in the horizontal plane (XY plane), and the horizontal plane is orthogonal to the optical axis O, as shown in B of FIG. 2 . As described above, the emission angle of the image light 1 emitted from the screen 12 includes an azimuth component φ (i.e., an angle component formed in the horizontal plane) and an elevation component θ (i.e., an angle component formed with the horizontal plane). Among them, each segmented area 23 is configured to have a different azimuth component φ.

[0159] B of Fig. 2 schematically shows an emission vector 3 (optical path) in a horizontal plane using a dotted arrow, and the emission vector 3 is an emission vector of the image light 1 emitted from the screen 12. Here, in the horizontal plane, the angle formed by the normal vector 4 and the emission vector 3 of the image light 1 corresponds to the azimuth component φ of the emission angle of the image light 1, wherein the normal vector 4 is the normal vector of the screen 12 at the emission position where the image light 1 is emitted.

[0160] B of FIG. 2 shows five emission vectors 3, of which the emission vector 3 passing through the reference position S is located in the middle of the five emission vectors 3. The starting points of the five emission vectors 3 (emission positions of the emitted image light 1) are points located on the divided areas 23 different from each other, and the azimuth angle components φ corresponding to the five emission vectors 3 are different from each other. Note that in the present embodiment, the elevation angle component θ of the emission angle set for each divided area 23 is set to the same value.

[0161] As described above, the image light 1 is divided into lines in the vertical direction by the plurality of division areas 23 , and the image light 1 obtained by the division is emitted in different directions by the plurality of division areas 23 in the horizontal plane, respectively.

[0162] For example, let's discuss the optical path extending toward the screen 12. As the screen 12 rotates, the optical path continuously intersects with different segmented areas 23. Therefore, the image light 1 segmented into lines is continuously emitted at different emission angles. This makes it easy to perform a stereoscopic display that is visible from all directions of 360 degrees.

[0163] In addition, an emission angle is set for each of the plurality of divided areas 23 shown in B of FIG. 2 so that the image light 1 emitted from each divided area 23 converges in the horizontal plane. In other words, the azimuth component φ of the emission angle in each divided area 23 is set so that the emission vectors 3 having their starting points in each divided area 23 converge. Here, a convergence position F in the horizontal plane is set around the screen 12, and the azimuth component φ is set so that the emission vectors 3 from the divided areas 23 pass through the convergence position F. Note that the convergence position F is, for example, a position in the horizontal plane. For example, a linear area extending parallel to the Z direction through the convergence position F is an area where the image light 1 emitted from each divided area 23 converges.

[0164] In B of FIG. 2 , the convergence position F is set in a straight line passing through the optical axis O and the reference position S in a horizontal plane. However, not limited thereto, the convergence position F may be set at any point where image light from each divided area 23 may converge. In addition, the distance from the optical axis O to the convergence position F is appropriately set according to, for example, the size of the screen 12 or the expected viewing distance.

[0165] As described above, in a configuration where the image light 1 emitted from each divided area 23 is converged, when the screen 12 is viewed from the convergence position F, for example, images projected respectively onto the plurality of divided areas 23 (angle controllers 22 ) can be viewed simultaneously.

[0166] 2C schematically shows the screen 12 shown in FIG. 2B rotated clockwise. Here, assuming that there is a viewpoint P of a viewer viewing the screen 12, a plurality of viewpoints P are set around the screen 12.

[0167] The viewpoints P among the plurality of viewpoints P are arranged annularly around the optical axis O. Furthermore, the distance from the optical axis O to the convergence position F is set to be the distance from the optical axis O to each viewpoint P. In other words, each viewpoint P is set to overlap with the convergence position F. In this case, the viewpoint image displayed on the screen 12 can be viewed at a high resolution at each viewpoint P. Furthermore, even when the screen 12 is viewed at a distance different from the distance from the convergence position F to the screen 12, the video (viewpoint image) on the entire screen 12 can be viewed during one rotation of the screen 12, wherein the viewable video (viewpoint image) is seen in the form of residual images of the plurality of linear videos respectively from the divided areas 23. This principle is similar to the principle described later with reference to FIG. 33.

[0168] In C of FIG. 2 , the reference position S is located at the lower side in the figure relative to the optical axis O at time t1. Therefore, at time t1, the image displayed on the screen 12 using the angle controller 22 (plurality of divided areas 23) can be viewed at the viewpoint P1 at the lower side in the figure, which is located on a straight line extending from the optical axis O to the reference position S. Therefore, the image displayed at time t1 is a viewpoint image toward the viewpoint P1.

[0169] Likewise, the reference position S is located at the lower left in the figure relative to the optical axis O at time t2, and the image is displayed toward the viewpoint P2. Therefore, the image displayed at time t2 is a viewpoint image toward the viewpoint P2. In addition, the reference position S is located at the left in the figure relative to the optical axis O at time t3, and the image is displayed toward the viewpoint P3. Therefore, the image displayed at time t3 is a viewpoint image toward the viewpoint P3.

[0170] As described above, the screen 12 is rotated, and the displayed image is switched at each rotation position (at each rotation timing). Therefore, different images can be switched for display with respect to a plurality of annularly arranged viewpoints P.

[0171] FIG. 3 schematically shows the characteristics of the diffusion angle performed by the screen.

[0172] Each of the plurality of segmented areas 23 includes a diffusion function for diffusing the image light 1 to emit the diffused image light 1 so as to display an image projected onto the area. In other words, each of the plurality of segmented areas 23 may diffuse the image light 1 so as to emit the diffused image light 1 at an emission angle set for the segmented area 23. For example, each segmented area 23 diffuses the image light 1 to provide a specific intensity distribution, wherein the diffusion is performed in a direction centered on an emission direction (determined based on the emission angle).

[0173] The characteristics of the diffusion angle of the image light 1 performed by the segmented area 23 are described below with reference to FIG. 3 .

[0174] A and B in FIG. 3 are schematic diagrams for describing the diffusion angle in the horizontal plane. In addition, C in FIG. 3 is a schematic diagram for describing the diffusion angle in a vertical plane orthogonal to the horizontal plane. A, B, and C in FIG. 3 schematically illustrate image light 1 diffused to be emitted from the segmented area 23, respectively. The solid arrows represent image light 1 emitted at the emission angle. In addition, the dotted arrows represent image light 1 diffusely emitted, wherein the diffusion is performed at an angle formed centered on a direction corresponding to the emission angle.

[0175] In the present embodiment, for the angle range of the diffused image light 1 in each of the plurality of divided areas 23, the angle range α in the horizontal plane orthogonal to the optical axis O is set to be smaller than the angle range β with respect to the horizontal plane. Here, the angle range α refers to the range of the azimuth angles in which the image light 1 is diffused, and the angle range β refers to the range of the elevation angles in which the image light 1 is diffused.

[0176] A of FIG. 3 shows image light 1 emitted along a horizontal plane from a segmented area 23 set at a reference position S. In this case, the azimuth component φ of the emission angle is 0 degrees. The image light 1 is diffused in an angle range α so as to be emitted in a horizontal plane in a normal direction parallel to the outer peripheral surface of the screen 12. In addition, B of FIG. 3 shows image light 1 emitted along a horizontal plane from a segmented area 23 set away from the reference position S. An azimuth component φ larger than the azimuth component shown in A of FIG. 3 is set for the segmented area. However, the angle range in which the image light 1 is diffused in the horizontal plane may also be similar to the angle range α shown in A of FIG. 3 .

[0177] In addition, C of FIG. 3 shows image light 1 emitted from the segmented area 23 set at the reference position S along a cross section (vertical plane orthogonal to the horizontal plane) including the optical axis O. The image light 1 is diffused in an angle range β larger than the angle range α, thereby being emitted in the vertical plane along the normal direction parallel to the outer peripheral surface of the screen 12. Note that the angle range β for diffusion in the vertical plane is set for another segmented area 23 similarly to the case of C of FIG. 3. In addition, the elevation component of the emission angle is 0 degrees in C of FIG. 3, and the image light 1 is emitted toward the front of the screen 12. The elevation component of the emission angle is not limited thereto, and for example, the screen 12 that emits the image light 1 upward or downward may be appropriately configured according to the application.

[0178] As described above, the divided area 23 includes an anisotropic diffusion function that diffuses the image light 1 at a small angle in the horizontal direction (azimuth direction) and diffuses the image light at a large angle in the vertical direction (elevation direction).

[0179] For example, when the angle range α in which the image light 1 is diffused in the horizontal direction is set to be large, it is conceivable that the image light 1 that should be emitted toward a certain viewpoint P is actually emitted toward another viewpoint P next to the viewpoint. Therefore, at a certain viewpoint P, a viewpoint image of another viewpoint P may be seen, and crosstalk may occur in the 3D image observed by the audience.

[0180] On the other hand, in this embodiment, by setting the angle range α to be smaller, such crosstalk can be fully avoided. In addition, by setting the angle range β to be larger than the angle range α, the elevation range of the viewpoint image can be viewed can be made larger. In this way, visible stereoscopic display can be achieved within a larger elevation range while preventing crosstalk.

[0181] The method of setting the diffuse light distribution is not limited. For example, the distribution in the horizontal direction is set to a top-hat distribution in which the light amount (brightness) changes in a rectangular shape, or is set to a Gaussian distribution. In this case, the angle range α is set to, for example, half the width of the light amount distribution of the diffuse light in the horizontal direction. In addition, the distribution in the vertical direction can also be set to a top-hat distribution or a Gaussian distribution.

[0182] The distribution of the diffused light is appropriately set so that crosstalk or moire fringes are prevented from occurring in a 3D image and the brightness of the 3D image is improved.

[0183] [Display Control]

[0184] FIG. 4 is a block diagram showing a functional configuration example of the image display device 100 .

[0185] The image display apparatus 100 includes an image reproducer 40 in addition to the above-described controller 19. The controller 19 and the image reproducer 40 may be configured using, for example, independent computers (computing devices) or a single computer.

[0186] Furthermore, the transmitting section 11 is provided with a projector main body 41 (PJ main body) and a projector driver 42 (PJ driver). Furthermore, the rotating mechanism 14 is provided with a motor main body 44 , a motor driver 45 , and a rotary encoder 46 .

[0187] The image reproducer 40 outputs image data of display content on the image display device 100. Here, the content displayed on the image display device 100 is a stereoscopic display content, and includes a moving image (video) or a still image that can be viewed stereoscopically. Therefore, the image data is data including a plurality of viewpoint images for performing stereoscopic display.

[0188] In this embodiment, the same viewpoint images can be displayed simultaneously, as described with reference to FIG2. Therefore, the image data is data for switching each viewpoint image at a high frame rate. For example, when a plurality of viewpoint images displayed within one rotation of the screen 12 are set as one image set, the image data is data including a plurality of image sets.

[0189] The projector main body 41 is provided with, for example, a light emitting element and a light modulator that modulates light emitted by the light emitting element to generate image light 1 .

[0190] The projector driver 42 operates the projector body 41 (light modulator) based on the image data (video signal) output by the image reproducer 40. In addition, the projector driver 42 outputs a frame trigger signal. The frame trigger signal is a timing signal that instructs the projector body 41 to display a viewpoint image (frame). For example, a timing signal indicating a viewpoint image at the start position of the image set to be displayed is output as the frame trigger signal. Note that a corresponding frame trigger signal may be output for each viewpoint image included in the image set.

[0191] The motor body 44 is an electric motor including, for example, a rotor and a stator (neither shown), and wherein the rotor rotates relative to the stator fixed to the base 10. The rotating mechanism 17 described with reference to FIG. 1 is connected to the rotor, and the screen 12 rotates by the rotation of the rotor.

[0192] The motor driver 45 supplies a driving current to the motor body 44 based on a rotation control signal output by the controller 19 , and rotates the rotor.

[0193] The rotary encoder 46 is configured using, for example, a code wheel that indicates the rotational position of the rotor and an encoder that detects the rotational position using the code wheel. The rotary encoder 46 is a sensor that measures the number of rotations (rotational speed) and the rotational position of the rotor (screen 12). The rotary encoder 46 outputs a screen position trigger signal. This is a trigger signal that indicates the rotational position of the screen 12. For example, a timing signal indicating that the screen 12 passes through a preset rotational position (for example, an origin position at a rotation angle of 0 degrees) is output as a screen position trigger signal. For example, the screen position trigger signal is used to control the phase of the rotation. In addition, an interval trigger signal indicating the interval at which the screen 12 rotates can be output. For example, an interval trigger signal is output at each specific angle interval (for example, 0.2 degrees) for speed control.

[0194] The controller 19 synchronizes the display of the viewpoint images composed of the image light 1 with the rotation of the screen 12, so that the viewpoint images can be viewed at the corresponding viewpoints P of the plurality of viewpoints P set around the screen 12. This is a setting performed to accurately synchronize a series of viewpoint images with the high-speed rotating screen 12, wherein the emitting section 11 switches the image light 1 to display a series of viewpoint images. In this way, an appropriate viewpoint image can be displayed for each of the plurality of viewpoints P.

[0195] In the present embodiment, the rotation mechanism 14 is controlled using the rotation control signal so that the rotation angle of the rotating screen 12 when displaying the viewpoint image is an angle corresponding to the viewpoint image.

[0196] 4 , the controller 19 reads a frame trigger signal provided by the projector driver 42 and a screen position trigger signal and an interval trigger signal provided by the rotary encoder 46. In addition, based on these trigger signals, the controller 19 generates a rotation control signal that controls, for example, the speed and phase of the rotational motion of the motor body 44.

[0197] Note that the frame trigger signal may be outputted not from the projector driver 42 but from the image reproducer 40. Fig. 4 schematically illustrates, using a dotted arrow, a frame trigger signal outputted by the image reproducer 40. In addition, both the projector driver 42 and the image reproducer 40 output the frame trigger signal, and the rotation control signal may be generated using these two frame trigger signals.

[0198] FIG5 schematically shows an example of image data.

[0199] Fig. 5 schematically shows image data 31 at the top, which includes viewpoint images 30 projected at a specific timing by the projector main body 41. The image data 31 is a two-dimensional image (frame image) displayed within one frame, and the center of the image data 31 coincides with the position where the optical axis O and the image data 31 intersect. Note that the actual image data 31 is video data including a plurality of frame images.

[0200] Furthermore, FIG. 5 schematically shows, at the bottom, a viewpoint image 30 projected onto the rotating screen 12 through the reflection mirror 13 .

[0201] For example, the viewpoint image 30 is projected onto the entire angle controller 22 set on the partial screen 12. In this case, the viewpoint image 30 observed in the two-dimensional plane is a circular sector image, as shown in FIG5. Note that the shaded area shown in FIG5 is the portion projected onto the segmented area 23 including the reference position S.

[0202] Note that when the screen 12 rotates, the position of the segmented area 23 moves. Therefore, in order to project the viewpoint image 30 onto the moved segmented area 23, it is necessary to change the position of the viewpoint image 30 in the image data 31. Specifically, the circular sector viewpoint image 30 rotates around the center of the image data 31. In addition, when the screen 12 rotates, the viewpoint P corresponding to the image displayed in the segmented area 23 changes.

[0203] For example, it is assumed that the total number of the plurality of annularly arranged viewpoints P is N. In this case, the image data 31 is data in which N viewpoint images 30 respectively corresponding to the N viewpoints P are continuously switched. In addition, the rotational position of each viewpoint image 30 is shifted by the viewpoint spacing set corresponding to the plurality of viewpoints P.

[0204] The controller 19 uses the frame trigger signal to specify the timing of displaying a reference frame (e.g., the viewpoint image 30 at the beginning of the image set displayed within one rotation). In addition, the screen position trigger signal is used to specify the rotation position of the screen 12. For example, the rotation of the screen 12 is controlled using the above information so that the appropriate viewpoint image 30 is projected at an appropriate position on the screen 12.

[0205] [Stereoscopic Display]

[0206] Fig. 6 is a schematic diagram for describing an overview of a stereoscopic display operation performed by an image display device. Here, Fig. 6 schematically shows viewpoint images 30 displayed on the screen 12, wherein the viewpoint images 30 are obtained when a character as a 3D content 33 is seen at a right viewpoint and when a character as a 3D content 33 is seen at a left viewpoint, respectively.

[0207] 6 , at time t3, it can be seen that the viewpoint P3 of the viewpoint image 30 coincides with the position (direction) of the right eye of the viewer 2 who is viewing the screen 12. Here, the right-eye viewpoint image 30 is displayed by the image reproducer 40 and the transmitting section 11. Therefore, the viewer 2 can view the right-eye viewpoint image 30 with his / her right eye at time t3.

[0208] Thereafter, the screen 12 is rotated. At time t4, the viewpoint P4 where the viewpoint image 30 can be viewed coincides with the position (direction) of the left eye of the viewer 2. Here, the left-eye viewpoint image 30 is displayed by the image reproducer 40 and the transmitting section 11. Therefore, the viewer 2 can view the left-eye viewpoint image 30 with his / her left eye at time t4.

[0209] The period between time t3 and time t4 is short, and the image viewed by the viewer 2 during this period is perceived as a residual image. Therefore, the viewer 2 perceives an image obtained by performing time multiplexing on time t3 and time t4. In other words, the viewer 2 perceives the residual image of the right eye viewpoint image 30 at time t4 together with the currently displayed left eye viewpoint image 30. In this way, the 3D content 33 displayed as the viewpoint image 30 can be stereoscopically perceived.

[0210] An example of displaying the respective viewpoint images 30 using the angle controller 22 (plurality of divided areas 23 ) is described in detail below.

[0211] FIG. 7 schematically illustrates an operation example of an angle controller for displaying a viewpoint image. FIG. 8 schematically illustrates an operation example of a segmentation area included in the angle controller. FIG. 7 and FIG. 8 illustrate an example in which viewpoints P among a plurality of viewpoints P are arranged in a ring around an optical axis O at a viewpoint spacing of 3 degrees. Here, each time the screen 12 rotates 3 degrees, the viewpoint image 30 is switched. In the following description, it is assumed that when observed from the screen 12, a straight line extending downward in the figure is defined as an azimuth angle of 0 degrees, and the angle increases clockwise.

[0212] 7 and 8 show a configuration example in which the screen 12 has a diameter of 100 mm and the distance from the optical axis O to each viewpoint P (convergence position) is 500 mm. Of course, the size of the screen 12 and the position of the viewpoint P are not limited and can be designed arbitrarily.

[0213] 7 shows at the top a viewpoint image 30 displayed using the angle controller 22 toward the viewpoint P corresponding to the azimuth angle of 0 degrees. The viewpoint image 30 is displayed by using the image light 1 diffused by each of the plurality of divided areas 23 included in the angle controller 22 and by using the diffused image light 1 emitted toward the viewpoint P corresponding to the azimuth angle of 0 degrees.

[0214] Hereinafter, the plurality of segmented regions 23 are referred to as a first segmented region 23, a second segmented region 23, . . . , and an nth segmented region 23 from the left in the drawing. Also, an image projected onto each segmented region 23 is referred to as a segmented image 34 of the viewpoint image 30.

[0215] 7 shows a rotation range in which the viewpoint image 30 is displayed toward the viewpoint P corresponding to the azimuth angle of 0 degrees at the lower part. This range is the same video range 35 in which the same viewpoint image 30 is projected onto the angle controller 22 and displayed on the angle controller 22 .

[0216] As shown in FIG7 , the same video range 35 is a range between the angle positions at the middle positions of the target viewpoint P and the viewpoints P adjacent to both sides thereof. For example, when the viewpoint spacing is a spacing of 3 degrees, the viewpoint P just before the viewpoint P corresponding to the azimuth angle of 0 degrees is a point corresponding to an azimuth angle of -3 degrees (357 degrees). In addition, the viewpoint P just after the viewpoint P corresponding to the azimuth angle of 0 degrees is a point corresponding to an azimuth angle of +3 degrees. Therefore, the same video range 35 corresponding to the viewpoint P at the azimuth angle of 0 degrees is a range between a point corresponding to an azimuth angle of -1.5 degrees (358.5 degrees) and a point corresponding to an azimuth angle of +1.5 degrees.

[0217] 8 schematically shows image light 1 diffusely emitted from the rightmost segmented area 23 (ie, the nth segmented area 23 ) among the plurality of segmented areas 23 included in the angle controller 22 . The segmented area 23 is an area where the rightmost segmented image 34 in the viewpoint image 30 is displayed.

[0218] When the screen 12 passes through the same video range 35, the same divided image 34 is displayed on each divided area 23. For example, when the viewpoint pitch is a pitch of 3 degrees and the screen 12 has a diameter of 100 mm, the length of the range in which the same divided image 34 is displayed is 2.62 mm on the circumference of the screen 12. When the screen 12 has passed through the range length, the divided image 34 included in the viewpoint image 30 and corresponding to the next viewpoint P is displayed on each divided area 23.

[0219] [Frame rate]

[0220] Here, a frame rate for performing 3D display is described. The table shown below is a table giving an example of the frame rate for switching the viewpoint image 30.

[0221] Here, it is assumed that a projector having a single DMD element is used as the emitting section 11, thereby performing one-bit grayscale image display of one color with a visible azimuth angle range of 360 degrees.

[0222] [Table 1]

[0223]

[0224] …Table (1)

[0225] Specific examples 1-12 are given in Table (1) above.

[0226] The frame rate (fps) of a 3D image is a frame rate for displaying 3D content. For example, this is a frame rate at which switching to a viewpoint image 30 corresponding to a specific viewpoint P is performed to display the viewpoint image 30 corresponding to the specific viewpoint P when the screen 12 is viewed at a specific viewpoint P. Actually, the viewpoint image 30 viewed at the specific viewpoint P is switched once within one rotation of the screen 12. In this case, the frame rate of the 3D image may also be the rotation period of the screen.

[0227] The total number of viewpoints P is the number of viewpoints P arranged in a plurality of circles.

[0228] The viewpoint interval (deg) is an interval set corresponding to a plurality of circularly arranged viewpoints. A value obtained by dividing a value corresponding to the entire circumference (360 degrees) by the total number of viewpoints P corresponds to the viewpoint interval.

[0229] The number of viewpoints generated simultaneously is the number of viewpoints that can be displayed simultaneously on the screen 12. In the present embodiment, the angle controller 22 shown in FIG2 is provided to form a screen 12 in which the number of viewpoints generated simultaneously is one. Note that the screen 12 in which the number of viewpoints generated simultaneously is at least two is a screen provided with a plurality of angle controllers 22 (refer to FIG27).

[0230] The rotation speed (Rpm) of the screen is the number of times the screen 12 is rotated by the rotating mechanism 14 .

[0231] The frame rate of the projector is a frame rate required when the transmitting section 11 actually switches the viewpoint images 30 .

[0232] For example, when the frame rate of the 3D image is constant, as shown in Table 1, the rotation speed of the screen and the frame rate of the projector are determined according to the total number of viewpoints P (viewpoint spacing) and the number of viewpoints generated simultaneously.

[0233] For example, when it is assumed that there are N viewpoints P and when the number of viewpoints generated simultaneously is 1, within one rotation of the screen 12, the viewpoint image 30 is displayed once for each viewpoint P. Therefore, the number of rotations of the screen 12 per second (Rpm / 60) is equal to the value of the frame rate of the 3D image (fps). In addition, the frame rate of the projector is a value obtained by multiplying the value of the frame rate of the 3D image by the total number N of viewpoints P. For example, assuming that the frame rate of the 3D image is set to 60 fps, the viewpoint spacing is a spacing of 3 degrees, and the number of viewpoints generated simultaneously is 1 (Specific Example 4 in Table 1). In this case, the rotation speed of the screen is obtained as follows: 60 seconds × 60fps = 3600Rpm. In addition, the total number N of viewpoints P is 120, and the frame rate of the projector is obtained as follows: 60fps × 120 = 7200fps.

[0234] In addition, for example, when it is assumed that there are N viewpoints P and the number of viewpoints generated simultaneously is M, the viewpoint image 30 can be displayed M times toward each viewpoint P within one rotation of the screen 12. Therefore, the number of rotations of the screen 12 per second is a value obtained by dividing the value of the frame rate (fps) of the 3D image by M. In addition, the frame rate of the projector is expressed as a value obtained by dividing the value of the frame rate (fps) of the 3D image by M, and multiplying the value obtained by the division by the total number N of viewpoints P. For example, it is assumed that the frame rate of the 3D image is set to 60fps, the viewpoint spacing is a spacing of 3 degrees, and the number of viewpoints generated simultaneously is 3 (Specific Example 5 in Table 1). In this case, the rotation speed of the screen is obtained as follows: 60 seconds × (60 fps / 3) = 1200Rpm. In addition, the total number N of viewpoints P is 120, and the frame rate of the projector is obtained as follows: (60fps / 3) × 120 = 2400fps.

[0235] As described above, the rotation speed of the screen 12 and the frame rate of the projector required by the transmitting section 11 are determined according to the frame rate of the 3D image for 3D display, the viewpoint distance (the total number N of viewpoints P), and the number of viewpoints generated simultaneously. Note that the above specific examples are only examples, and the frame rate of the 3D image, the viewpoint distance, etc. may be appropriately set according to the application of the image display device 100.

[0236] [Division Area and Crosstalk]

[0237] 9 schematically shows a configuration example of the segmented area 23. The number of segmented areas 23 set in the angle controller 22, that is, the number of segments (video segmentation number) by which the image projected on the screen 12 is segmented, is described below. Here, it is assumed that the area used as the angle controller 22 remains unchanged.

[0238] For example, FIG9 shows an angle controller 22 in which the number of video divisions is set to 2. In this case, two division areas 23 are provided, and image light 1 is emitted from each division area 23 toward the viewpoint P. Likewise, in the case of an angle controller 22 in which the number of video divisions is set to 3, image light 1 is emitted from each of the three division areas 23 toward the viewpoint P. Furthermore, in the case of an angle controller 22 in which the number of video divisions is set to n (here n>3), image light 1 is emitted from each of the n division areas 23 toward the viewpoint P.

[0239] As shown in FIG9 , as the number of video divisions (the number of division areas 23) increases, the circumferential length (the width in the left-right direction in the figure) set for one division area 23 becomes smaller. Therefore, the image light 1 emitted from each division area 23 to the viewpoint P has a smaller width. This means that when the number of video divisions increases, the range of the division image 34 displayed on each division area 23 that can be viewed becomes smaller.

[0240] FIG. 10 is a schematic diagram for describing the relationship between the segmented areas and the crosstalk.

[0241] For example, when the number of video divisions is 2 (when two division areas 23 are formed), as shown in the upper portion on the left side in FIG. 10 , the width of the image light 1 emitted from each division area 23 is half the width of the viewpoint image 30. In this state, the viewpoint image 30 of P6 is visible not only at the center viewpoint P6 where the viewpoint image 30 should be displayed, but also at the adjacent viewpoints P5 and P7 located on both sides of the center viewpoint P6, as shown in the middle portion on the left side in the figure. In this case, crosstalk may occur in viewpoints P5 and P7 due to the viewpoint image 30 of viewpoint P6 being visible, and this may cause degradation of image quality.

[0242] 10, the screen 12 whose video division number is two rotates to switch from the viewpoint image 30 of viewpoint P6 to the viewpoint image 30 of viewpoint P7. In this case, the viewpoint image 30 of viewpoint P7 is also visible at viewpoint P6, and crosstalk may occur at viewpoint P6 because the viewpoint image 30 of viewpoint P7 can be seen.

[0243] As described above, when the number of video divisions is small and the image light 1 emitted from the division area 23 has a large width, crosstalk may easily occur depending on the viewpoint interval.

[0244] On the other hand, when the number of video divisions is n (when n divided areas 23 are formed), as shown in the upper right portion of Fig. 10, the width of the image light 1 emitted from each divided area 23 has a size obtained by dividing the width of the viewpoint image 30 by n. Therefore, compared with the case where the number of video divisions is 2, the image light 1 in this case has a sufficiently small width.

[0245] Therefore, the image light 1 is emitted only toward the central viewpoint P6 where the viewpoint image 30 should be displayed, and the viewpoint image 30 of P6 is not visible at the adjacent viewpoints P5 and P7 located on both sides of the viewpoint P6, as shown in the middle portion on the right side of the figure. In addition, it is assumed that the screen 12 with a video division number n is rotated to switch from the viewpoint image 30 of the viewpoint P6 to the viewpoint image 30 of the viewpoint P7, as shown in the lower right portion of Figure 10. In this case, the viewpoint image 30 of the viewpoint P7 is also not visible at the viewpoint P6 because the image light 1 has a sufficiently small width.

[0246] As described above, if the number of divided areas 23 (video division number) is large, the image light 1 emitted from each divided area 23, that is, the linear image (divided image 34) concentrated on the viewpoint P, has a smaller width. Therefore, crosstalk is reduced, and thus image display with high image quality can be performed. In addition, according to, for example, the size or application of the image display device 100, the minimum video division number and the like can be set to be within a range within which the crosstalk level is acceptable.

[0247] [Image display using black stripe area]

[0248] As a method for reducing the above-mentioned crosstalk between viewpoints P, the inventors have invented a method for forming a stripe area between the divided images 34 displayed on the respective divided areas 23, where no image is displayed on the stripe area. Here, the area where no image is displayed can be regarded as a black area where no image light 1 is emitted on the transparent screen 12. Hereinafter, the area where no image is displayed is referred to as a black stripe area.

[0249] When the viewpoint spacing is relatively small, the method performed using the black stripe area is particularly effective. On the contrary, when the viewpoint spacing is large enough, crosstalk between viewpoints P is not likely to occur. Therefore, it is possible to appropriately perform image display without using the black stripe area. In this case, the image quality is not affected by the black stripe area. When the image display device 100 is formed, it is preferred to verify the image quality balance affected by crosstalk, moire fringes, or resolution reduction for each area provided based on the viewpoint spacing to determine the diffusion angle performed by the HOE or whether to provide a black stripe area.

[0250] The method performed using the black stripe area is described in detail below.

[0251] Fig. 11 schematically shows an example of performing image display on the transparent screen 12 including the segmented area and the non-diffusion area. A method for providing a black stripe area in the structure of the transparent screen 12 is described below with reference to Fig. 11 .

[0252] A and B in Fig. 11 schematically show the structure of the viewpoint image 30 and the screen 12. In the viewpoint image 30 shown in A of Fig. 11, the area in which the image can be displayed is indicated in the form of a gray area.

[0253] In addition, the transparent screen 12 shown in B of FIG11 is provided with a plurality of segmented areas 23 and a plurality of non-diffusing areas 24. Here, the non-diffusing area 24 is an area which is formed between the segmented areas 23 adjacent to each other and does not diffuse the image light 1. In other words, it can also be said that the non-diffusing area 24 is a transparent area for the image light 1 and is a gap provided between the segmented areas 23.

[0254] In FIG. 11 , the non-diffusion region 24 serves as a black stripe region.

[0255] On the transparent screen 12 shown in B of Fig. 11, segmented areas 23 in which an image can be displayed by diffused image light 1 are indicated as gray areas. Furthermore, non-diffusion areas 24 in which no image is displayed are indicated as white areas.

[0256] For example, interference fringes serving as HOEs are not formed in the non-diffusion region 24. Therefore, the image light 1 incident on the non-diffusion region 24 passes through the transparent screen 12 without being diffracted, and is not emitted or diffused at a specific emission angle.

[0257] As shown in A of Fig. 11, a viewpoint image 30 that can display an image in all regions is projected onto the screen 12a. In this case, no image is displayed on the non-diffusion region 24. Therefore, for an image displayed on the screen 12a, the image light 1 emitted from each segmented region 23 has a smaller width than the segmented image 34 included in the viewpoint image 30. This can substantially reduce crosstalk between viewpoints P.

[0258] Fig. 12 schematically shows an example of display control performed using the screen shown in Fig. 11, which includes a segmented area and a non-diffusion area. The screen 12a provided with the non-diffusion area 24 between the segmented areas 23 can reduce the crosstalk that occurs when the viewpoint P is changed. The display control performed using the screen 12a when the viewpoint P is changed is described below with reference to Fig. 12.

[0259] FIG. 12 schematically shows, in the form of a stripe area, that the screen 12 passes through a projection position (PJ projection position) onto which the emitting section 11 projects the image light 1. In addition, the dark gray area corresponds to the area where the image light 1 is projected, and the light gray area corresponds to the segmented area 23 provided in the screen 12. Note that when the area where the image light 1 is projected and the segmented area 23 overlap each other, the segmented area 23 is located on the area where the image light 1 is projected. In addition, the figure schematically shows the emission vector of the image light 1 in each segmented area 23 using a thick arrow.

[0260] Here, it is assumed that the screen 12 rotates to shift from right to left in the figure. In addition, FIG12 shows the states of the screen 12 at times t1, t2, t3, t4, and t5 from the top.

[0261] In the example shown in FIG. 12 , switching between the ON state and the OFF state related to the image display composed of the image light 1 is performed according to the positional relationship between the projection range 36 and the divided area 23. Here, the projection range 36 is a range corresponding to the projection position (PJ projection position) of the projected image light 1, and the projection position is represented by dividing the screen circumferentially with the viewpoint pitch. The projection range 36 is a fixed range independent of the rotation of the screen 12. In FIG. 12 , the viewpoint pitch is set to 3 degrees, and the range obtained by dividing the screen with the dotted line is the projection range 36. The image formed by arranging the divided images 34 projected on the respective projection ranges 36 is the viewpoint image 30 displayed on the same video range 35 of the viewpoint P.

[0262] As an example, the switching timing between the ON state and the OFF state related to the image display constituted by the image light 1 is described using the segmented area 23 (hereinafter referred to as the target segmented area 23 ) passing through the fourth projection range 36 from time t1 to time t5 .

[0263] For example, at time t1, the target segmented area 23 overlaps the boundary between the projection range 36 and is located between the fifth projection range 36 and the fourth projection range 36. For example, when the viewpoint image 30 is projected in this state, the image light 1 emitted from the target segmented area 23 is emitted toward the same video range 35 of the viewpoint P that displays the viewpoint image 30 immediately before time t1. This causes the occurrence of crosstalk. Therefore, the image display composed of the image light 1 is set to OFF (PJ-OFF) at time t1.

[0264] At time t2, the target segmented area 23 has passed the boundary between the fifth projection range 36 and the fourth projection range 36, and is located in the fourth projection range 36. Therefore, when the viewpoint image 30 is projected in this state, the image light 1 emitted from the target segmented area 23 is not emitted to the same video range 35 of the viewpoint P that has just passed. This results in no crosstalk. Therefore, the display of the image composed of the image light 1 is set to ON (PJ-ON) at time t2. In addition, the target segmented area 23 is also located in the fourth projection range 36 at time t3 and time t4. Therefore, the image display is set to ON.

[0265] Note that it can also be said that the period from time t2 to time t4 is a period in which the boundary between the projection range 36 and the non-diffusion region 24 where no image is displayed overlaps with each other.

[0266] The target segmented area 23 moves, and then the target segmented area 23 overlaps with the boundary between the fourth projection range 36 and the third projection range 36 at time t5. For example, when the next viewpoint image 30 is projected in this state, the image light 1 emitted from the target segmented area 23 is emitted toward the same video range 35 of the viewpoint P displaying the viewpoint image 30. This causes the occurrence of crosstalk. Therefore, the image display composed of the image light 1 is set to OFF (PJ-OFF) at time t5.

[0267] As described above, in Fig. 12, when the boundary between the projection ranges 36 obtained by dividing with the angular intervals (viewpoint intervals) of the plurality of viewpoints P and the divided area 23 overlap each other, the image display composed of the image light 1 is set to OFF. When the boundary between the projection ranges 36 and the non-diffusion area 24 overlap each other, the image display composed of the image light 1 is set to ON.

[0268] This can reduce crosstalk that occurs when the viewpoint P is changed, thereby performing stereoscopic display with high quality.

[0269] Fig. 13 schematically shows an example of image display using a viewpoint image 30 including a display area and a non-display area. A method for providing a black stripe area in the viewpoint image 30 is described below with reference to Fig. 13 .

[0270] A and B in FIG. 13 schematically show the structures of the viewpoint images 30 and the screen 12 .

[0271] In the viewpoint image 30a shown in A of FIG. 13 , the area where the image is displayed (display area 37) is represented in the form of a gray area. In addition, the area where the image is not displayed (non-display area 38) is represented in the form of a black area. In addition, in the viewpoint image 30a, the display area 37 and the non-display area 38 are set within one viewpoint spacing. As described above, the viewpoint image 30a shown in A of FIG. 13 is an image in which the display area 37 and the non-display area 38 are set in the angular spacing (viewpoint spacing) of multiple viewpoints. In FIG. 13 , the non-display area 38 is used as a black stripe area.

[0272] Note that a plurality of divided areas 23 are formed without gaps on the screen 12 shown in B of FIG. 13 .

[0273] For example, forming the divided areas without gaps can display images on all areas on the screen 12 shown in B of FIG. 13. The viewpoint image 30a including the stripe-shaped non-display area 38 is projected onto such a screen 12. In this case, since no image is displayed on the non-display area 38, the width of the image light 1 emitted from each divided area 23 is smaller than the width of the divided area 23 for the image displayed on the screen 12. This results in sufficient reduction of crosstalk between the viewpoints P.

[0274] Fig. 14 schematically shows an example of display control using the viewpoint image 30a shown in Fig. 13, the viewpoint image 30a including the display area 37 and the non-display area 38. Using the viewpoint image 30a with the non-display area 38 between the display areas 37 can reduce the crosstalk that occurs when the viewpoint P is changed. The display control using the viewpoint image 30a when the viewpoint P is changed is described below with reference to Fig. 14.

[0275] In Fig. 14, the dark gray area corresponds to the display area 37 of the display image in the viewpoint image 30a. Note that the area located between the display areas 37 corresponds to the non-display area 38. In addition, the light gray area corresponds to the segmented area 23 provided in the screen 12. In addition, when the display area 37 overlaps the segmented area 23, the display area 37 is located on the segmented area 23. In addition, the figure schematically shows the emission vector of the image light 1 in each segmented area 23 using thick arrows.

[0276] In the example shown in FIG. 14 , switching between the ON state and the OFF state related to the image display by the image light 1 is performed according to the positional relationship between the display area 37 and the divided area 23 set with the viewpoint distance.

[0277] As an example, the switching timing between the ON state and the OFF state related to the image display constituted by the image light 1 is described using the segmented area 23 (hereinafter referred to as the target segmented area 23 ) passing through the fourth projection range 36 from time t1 to time t5 .

[0278] For example, at time t1, the target segmented area 23 overlaps with the boundary between the display area 37 and the non-display area 38. For example, when the viewpoint image 30 is projected in this state, the target segmented area 23 overlaps with the display area 37 projected onto the fourth projection range 36 and the display area 37 projected onto the fifth projection range 36. Therefore, the image light 1 is emitted from the target segmented area 23 toward the same video range 35 of the viewpoint P where the viewpoint image 30 is displayed immediately before time t1. This causes the occurrence of crosstalk. Therefore, the display of the image composed of the image light 1 is set to OFF (PJ-OFF) at time t1.

[0279] At time t2, the target segmented area 23 has passed the boundary of the display area 37 projected on the fifth projection range 36, and only the display area 37 projected on the fourth projection range 36 is located in the target segmented area 23. Therefore, when the viewpoint image 30 is projected in this state, the image light 1 emitted from the target segmented area 23 is not emitted to the same video range 35 of the viewpoint P that has just passed. This results in no crosstalk. Therefore, the display of the image composed of the image light 1 is set to ON (PJ-ON) at time t2. In addition, the display area 37 projected on the fourth projection range 36 is also located in the target segmented area 23 at time t3 and time t4. Therefore, the image display is set to ON.

[0280] Note that it can also be said that the period from time t2 to time t4 is a period in which the target segmented region 23 does not overlap with any boundary of the display region 37 .

[0281] The target segmented area moves 23, and then the target segmented area 23 overlaps the display area 37 projected on the fourth projection range 36 and the display area 37 projected on the third projection range 36 at time t5. For example, when the next viewpoint image 30 is projected in this state, the image light 1 emitted from the target segmented area 23 is emitted toward the same video range 35 of the viewpoint P displaying the viewpoint image 30. This causes the occurrence of crosstalk. Therefore, the display of the image composed of the image light 1 is set to OFF (PJ-OFF) at time t5.

[0282] As described above, in FIG. 14 , when the boundary of the segmented area 23 and the display area 37 overlap with each other, the display of the image formed by the image light 1 is set to OFF, and when the boundary of the segmented area 23 and the display area 37 do not overlap with each other, the display of the image formed by the image light 1 is set to ON.

[0283] This makes it possible to reduce crosstalk that occurs when the viewpoint P is changed by performing image processing only on the viewpoint image 30, thereby facilitating high-quality stereoscopic display.

[0284] Fig. 15 schematically shows an example of image display using a screen 12a and a viewpoint image 30a, wherein the screen 12a includes a segmented area and a non-diffusion area, and the viewpoint image 30a includes a display area and a non-display area. In Fig. 15, the screen 12a shown in Fig. 11 and including the non-diffusion area 24 and the viewpoint image 30a shown in Fig. 13 and including the non-display area 38 are used. Here, the segmented area 23 is represented in the form of a light gray area, and the display area 37 is represented in the form of a dark gray area.

[0285] In the example shown in FIG. 15 , when the boundary of the projection range 36 and the segmented area 23 overlap each other, the image display composed of the image light 1 is set to OFF, and when the boundary of the projection range 36 and the non-diffusion area 24 overlap each other, the image display composed of the image light 1 is set to ON. This can prevent the image light 1 from being emitted from one segmented area 23 that crosses the adjacent projection range 36. This can reduce crosstalk. In addition, since the non-display area 38 is provided in the viewpoint image 30a, even if the timing of turning the image display ON or OFF is only slightly offset, crosstalk can be sufficiently reduced.

[0286] Furthermore, for example, when the boundary of the divided area 23 and the display area 37 overlap each other, the image display composed of the image light 1 can be set to OFF, and when the boundary of the divided area 23 and the display area 37 do not overlap each other, the image display composed of the image light 1 can be set to ON. This can prevent the image light 1 from being emitted from one divided area 23 straddling the display areas 37 adjacent to each other. This can reduce crosstalk.

[0287] In addition, since the screen 12a is provided with the non-diffusion area 24, crosstalk can be sufficiently reduced even if the non-display area 38 has a small width. This can make the width of the display area 37 larger, thereby reducing the degradation of image quality caused by, for example, the black stripe area becoming conspicuous.

[0288] [Image display without using black stripe area]

[0289] As described above, when the non-diffusion area 24 or the non-display area 38 used as the black stripe area is provided, crosstalk can be reduced. On the other hand, by providing the black stripe area (refer to A of FIG. 17 ), the stripe area where no image is displayed becomes conspicuous. Therefore, it is not necessary to provide the black stripe area.

[0290] 16A and 16B schematically show an example of image display without using a black stripe region.

[0291] FIG16A schematically shows an example of performing image display using the screen 12 in which the segmented areas 23 are formed without gaps. The screen 12 shown in FIG16A has a configuration similar to that of the screen 12 shown in, for example, B of FIG13 , and is a screen in which emission angles are discretely set for each segmented area 23 formed without gaps. In addition, the viewpoint image 30 projected onto the screen 12 in FIG16A has a configuration similar to that of the viewpoint image 30 shown in, for example, A of FIG11 , and is an image obtained using a plurality of segmented images 34 arranged without gaps. In FIG16A , as described above, image display is performed in a case where the non-diffusion area 24 is not provided in the screen 12 or the non-display area 38 is not provided in the viewpoint image 30.

[0292] When the screen 12 rotates, the segmented area 23 moves circumferentially (leftward in FIG. 16A ). Here, when the area ratio of the portion of the segmented area 23 overlapping one projection range 36 is greater than or equal to a certain threshold, the image display is set to ON, and in other cases, the image display is set to OFF. The area ratio of the portion of the segmented area 23 overlapping one projection range 36 may be referred to as the area ratio hereinafter.

[0293] The area in the segmented area 23 that overlaps with one projection range 36 is referred to as an overlapped area 27. Fig. 16A schematically shows a shaded area as an overlapped area 27 formed in the segmented area 23 that overlaps with the fourth projection range 36. The above area ratio is, for example, a percentage (S1 / S0) of the area S1 to the area S0 in the segmented area 23.

[0294] Typically, the specific threshold is set to a value greater than or equal to 0.5 and less than or equal to 1, that is, a value greater than or equal to 50% and less than or equal to 100%. For example, when the specific threshold is 0.6, an image of a portion (overlapping area 27) of more than 60% of the segmented image 34 projected onto the projection range 36 is displayed at an appropriate position.

[0295] For example, at time t1, the target segmented area 23 overlaps with the fourth projection range 36, and the area of ​​the overlapping area 27 is increasing. At this time, the area ratio is less than a specific threshold. When the viewpoint image 30 is projected in this state, more image light 1 is emitted to the same video range 35 of the viewpoint P where the viewpoint image 30 is just displayed. This causes the occurrence of crosstalk. Therefore, the image display composed of the image light 1 is set to OFF (PJ-OFF) at time t1.

[0296] At times t2 to t4, the area ratio of the overlapping region 27 to the target segmented region 23 is greater than a specific threshold. Therefore, the image display composed of the image light 1 is set to ON (PJ-ON). In this case, the ratio of the portion displayed at the appropriate position in the segmented image 34 is greater than or equal to a specific threshold. Note that the image light 1 corresponding to the remaining portion of the segmented image 34 is emitted to the same video range 35 of the viewpoint P of the previous display viewpoint image 30, or to the same video range 35 of the viewpoint P of the next display viewpoint image 30. However, in this case, the percentage of the image light 1 is relatively small. As described above, the image light 1 leaked into the other same video ranges 35 at times t2 to t4 is less likely to be perceived as crosstalk.

[0297] In addition, after time t3, the target segmented area 23 overlaps with the third projection range 36, and the area of ​​the overlapping area 27 is decreasing. In addition, the area ratio is less than a specific threshold at time t5. In this case, more image light 1 is emitted to the same video range 35 of the viewpoint P that subsequently displays the viewpoint image 30. This may cause the occurrence of crosstalk. Therefore, the image display composed of the image light 1 is set to OFF (PJ-OFF) at time t5.

[0298] As described above, switching between the ON state and the OFF state related to image display is performed at appropriate timing, and this makes it possible to reduce crosstalk even when the non-diffusion area 24 or the non-display area 38 serving as a black stripe area is not provided.

[0299] Note that it is not necessary to perform switching control between the ON state and the OFF state related to the image display. For example, depending on the interval of the viewpoints P (viewpoint spacing) or the size of the screen 12, the crosstalk may be small enough without turning off the image display. In this case, for example, the switching control of the viewpoint image 30 may be performed when the area ratio of the overlap area 27 to the segmented area 23 exceeds 50% while the image display remains ON.

[0300] When the method shown in FIG. 16A is applied, a 3D image is displayed without using the non-diffusion area 24 or the non-display area 38 used as a black stripe area. This prevents the resolution of the 3D image from being reduced due to the black lines in the form of stripes. This enables stereoscopic display to be performed with high resolution and high quality.

[0301] FIG16B schematically shows an example of performing image display using a screen in which the emission angle changes continuously. The screen 12 in which the emission angle is set for each segmented area 23 has been mainly described above. On the other hand, the angle controller 22 provided in the screen 12b shown in FIG16B can emit the image light 1 at different emission angles for each position where the image light 1 is incident on the screen 12b. Specifically, the angle controller 22 of the screen 12b is set so that the emission angle changes continuously. As described above, in the case of the screen 12b, the emission angle is changed not for each area but for each position.

[0302] The HOE included in the screen 12b is formed by changing the path of the object light irradiated onto the screen 12b using, for example, a lens or a curved mirror. For example, for each position on the screen 12, the path of the object light passing through the lens is continuously changed. In this way, an HOE whose emission angle continuously changes for each position can be formed. In addition, the HOE can be exposed to light at one time over the entire surface of the angle controller 22. This can shorten the time required for the exposure process.

[0303] Switching between the ON state and the OFF state related to image display is performed at an appropriate timing, and crosstalk can be reduced even when such a screen 12b is used.

[0304] In the example shown in FIG. 16B , the virtual segmented area (virtual segmented area 25) has a smaller width than the projection range 36 corresponding to the viewpoint spacing. For example, the width of the virtual segmented area 25 is set to be less than or equal to a value corresponding to the diffusion angle in the horizontal plane. When the boundary between the virtual segmented area 25 and the projection range 36 overlaps, the image display composed of the image light 1 is set to OFF, and when the boundary between the virtual segmented area 25 and the projection range 36 does not overlap, the image display composed of the image light 1 is set to ON.

[0305] For example, at time t1, the virtual segmented area 25 shown in FIG. 16B overlaps the boundary between the projection ranges 36 and is located between the fifth projection range 36 and the fourth projection range 36. When the viewpoint image 30 is projected in this state, crosstalk occurs. Therefore, the image display composed of the image light 1 is set to OFF (PJ-OFF) at time t1.

[0306] At time t2 to t4, the virtual divided area 25 is located in the fourth projection range 36. Therefore, the image display is set to ON (PJ-ON).

[0307] In addition, the virtual divided area 25 overlaps the boundary between the fourth projection range 36 and the third projection range 36 at time t5. When the next viewpoint image 30 is projected in this state, crosstalk occurs. Therefore, the image display composed of the image light 1 is set to OFF (PJ-OFF) at time t5.

[0308] As described above, even when the screen 12b with a continuously changing emission angle is used, crosstalk can be reduced, thereby achieving high-quality stereoscopic display. In addition, as in the case of FIG. 16A, the black stripe area is not used. This can prevent the resolution of the 3D image from being reduced due to the stripe-shaped black lines.

[0309] [Position adjustment of black stripe area]

[0310] FIG. 17 is a schematic diagram for describing a method for adjusting the position of a black stripe region.

[0311] A of Fig. 17 schematically shows on the left side a viewpoint image 30 displayed when the position of the black stripe region (non-diffusion region 24 or non-display region 38) is fixed, wherein the black stripe region is highlighted. For example, the black stripe region is a region where no image is displayed on the screen 12. Therefore, an image with stripes may be displayed at a reduced resolution, as shown on the right side of A of Fig. 17.

[0312] Here, a method for preventing such a reduction in resolution is described.

[0313] B of Fig. 17 shows an example in which a viewpoint image 30 without a gap is projected onto the screen 12a, in which the segmented areas 23 are separated from each other by the non-diffusion area 24. In this case, for example, the timing of displaying the viewpoint image 30 or the rotation of the screen 12 is controlled to change the relative position of the segmented area 23 in the projection range 36. B of Fig. 17 schematically shows the state of the screen 12 at time t1, t2, and t3, in which the screen 12 is shifted according to the rotation period of the screen 12.

[0314] For example, at time t1, the viewpoint image 30 is displayed in a state where the segmented area 23 is located in the middle part of the projection range 36 (the image display is switched to ON). Furthermore, at time t2, the viewpoint image 30 is displayed in a state where the segmented area 23 is in contact with the right boundary of the projection range 36. Furthermore, at time t3, the viewpoint image 30 is displayed in a state where the segmented area 23 is in contact with the left boundary of the projection range 36. As described above, each time the screen 12 rotates, the relative position of the segmented area 23 in the projection range 36 changes. As a result, as shown in the lower part of B of FIG. 17 , the images at times t1, t2, and t3 are sequentially displayed in each projection range 36. This makes it possible to display an image with a small overall brightness change in the entire area in the projection range 36 with high resolution.

[0315] 17C shows an example in which the viewpoint image 30a including the non-display area 38 is displayed on the screen 12 in which the divided area 23 is formed without a gap. In this case, for example, by changing the position of the display area 37 (non-display area 38) in the viewpoint image 30a or the timing of displaying the viewpoint image 30a, the relative position of the display area 37 (non-display area 38) in the projection range 36 is changed.

[0316] For example, at time t1, the viewpoint image 30 is displayed in a state where the display area 37 is located in the middle part of the projection range 36 (the image display is switched ON). Furthermore, at time t2, the viewpoint image 30 is displayed in a state where the display area 37 is in contact with the right boundary of the projection range 36. Furthermore, at time t3, the viewpoint image 30 is displayed in a state where the display area 37 is in contact with the left boundary of the projection range 36. As a result, as in the case of B of FIG. 17 , an image display with a small brightness variation as a whole can be displayed at high resolution in the entire area in the projection range 36.

[0317] As described above, by shifting the positions of the non-diffusion regions 24 or the non-display regions 38 as black stripe regions (ie, the timing (position) of inserting black into the viewpoint image 30 ), the area for displaying an image can be enlarged, thereby improving the resolution.

[0318] [Configuration example of each structural element]

[0319] FIG. 18 schematically shows a configuration example of the cover portion.

[0320] For example, a cover portion 15a having a cylindrical shape is used as shown in A of FIG18. In this case, the diameter and thickness of the cover portion 15a are set so that the cover portion 15a is adapted to the screen 12 arranged inside the cover portion 15a. This enables the cover portion 15a and the screen 12 to present a unified appearance. In addition, the entire device including the screen 12 has a cylindrical shape, and this can provide an excellent design.

[0321] Note that the image light 1 emitted from the screen 12 may be refracted by passing through the cylindrical cover portion 15a. This causes the azimuth component of the emission angle (emission azimuth) of the image light 1 set for the screen 12 to shift. For example, the image light 1 has a smaller emission azimuth after passing through the cover portion 15a than the original emission azimuth. Taking into account the refraction caused by the cover portion 15a, the emission azimuth set for the screen 12 is corrected so that no shift is caused due to the refraction.

[0322] Furthermore, a cover portion 15b having a rectangular parallelepiped shape may be used as shown in B of Fig. 18. In this case, the cover portion 15b may be a member formed by bonding transparent wall members, or a structural member that supports the corresponding side faces, for example, may be provided.

[0323] Furthermore, the shape of the cover portion 15 is not limited, and for example, the cover portion 15 having a dome shape or the cover portion 15 having a polygonal column shape may be used.

[0324] FIG. 19 schematically shows an arrangement example of the reflecting mirror 13 .

[0325] For example, the reflector 13 may be fixed to the screen 12 as shown in A of Fig. 19. In this case, for example, since the cover 15 is not included in the optical system for making the image light 1 incident on the screen 12, the cover 15 can be easily removed. This makes it possible to obtain a device that can be simply and easily maintained.

[0326] In addition, the reflector 13 may be fixed to the cover portion 15, as shown in B of FIG. 19 . This configuration is similar to the configuration shown in FIG. 1 . In this case, only the screen 12 rotates, and the reflector 13 does not rotate. For example, when the position of the reflector 13 is shifted by rotation, the incident position of the image light 1 on the screen 12 may also shift. When the reflector 13 is not provided at the screen 12 but at the cover portion 15, the position of the reflector 13 can be prevented from shifting due to rotation. As described above, the sensitivity to the shift caused by the rotation of the screen 12 is reduced. This can prevent the degradation of image quality due to the shift caused by rotation.

[0327] Furthermore, the method for arranging the reflector 13 is not limited, and the reflector 13 may be fixed to, for example, a structural member other than the cover portion 15 and the screen 12 .

[0328] FIG. 20 schematically shows a configuration example of a cross section of a screen and a cover portion.

[0329] For example, the screen 12 is formed by bonding an optical film 51 serving as the transmissive HOE 20 to a transparent substrate 50. A resin material such as acrylic resin (PMMA), polycarbonate resin (PC), polystyrene resin (PS), or cycloolefin polymer (COP) may be used as the transparent substrate 50. In addition, the transparent substrate 50 may be formed using, for example, glass.

[0330] Here, a cross section of the screen 12 and the cover portion 15 is described, wherein the left side in the figure is the inner side of the screen 12 (the side of the optical axis O).

[0331] In A of Fig. 20, the optical film 51 is bonded to the inner side of the transparent base material 50. This can prevent the optical film 51 from being damaged by contact with the cover part 15, or prevent the optical film from becoming dirty when being handled.

[0332] 20B, the optical film 51 is bonded to the outer side of the transparent substrate 50. In this case, the manufacturing process is simpler than when the optical film 51 is bonded to the inner side of the transparent substrate 50. This can reduce the manufacturing cost.

[0333] In C of FIG. 20 , the optical film 51 is bonded to the transparent substrate 50 through an optically clear adhesive (OCA 52). Here, the OCA 52 is bonded to the inner side of the transparent substrate 50, and the optical film 51 is bonded to the OCA 52. Note that the optical film 51 may be bonded to the outer side of the transparent substrate 50 through the OCA 52. Use of the OCA improves the bonding reliability of the transparent substrate 50 and the optical film 51.

[0334] In D of FIG. 20 , an anti-reflection film (AR film 53) is provided. In the example shown in D of FIG. 20 , the AR film 53 is bonded to the inside of the transparent substrate 50, the outside of the transparent substrate 50, the inside of the cover portion 15, and the outside of the cover portion 15. Note that the AR film 53 is bonded to the inside of the transparent substrate 50 through the optical film 51. Of course, the AR film 53 may also be bonded to the outside of the transparent substrate 50 through the optical film 51.

[0335] By using the AR film 53, it is possible to prevent the generation of observable ghost images due to the reflection of external light. In addition, the reflected image light 1 is reduced before being diffracted by the HOE. This can improve the brightness of the image.

[0336] Note that the bonded portion may be formed when bonding the AR film 53. For example, the bonded portion of the AR film 53 indicates a position located before or after the 3D image, and may allow the user to more strongly perceive that the 3D image is displayed inside the cover portion 15.

[0337] Furthermore, an AR coating may be formed using, for example, a dip coating method, instead of the AR film 53. In this case, a seamless AR coating can be provided, which can improve transparency.

[0338] FIG. 21 schematically shows a configuration example of a rotating mechanism.

[0339] In FIG. 21A and FIG. 21B, a hollow motor 55 is used as a motor of the rotating mechanism 14. As shown in FIG. 21A, the hollow motor 55 is a motor that is hollow in a portion through which a rotating shaft passes. The screen 12 is fixed to the hollow motor 55 by the rotating mechanism 17 (coupling member) described with reference to FIG. 1. As described above, the rotating mechanism 14 includes a hollow motor that rotates around a specific axis.

[0340] In addition, when the hollow motor 55 is used, at least a portion of the transmitting portion 11 is arranged in the opening 56 of the hollow motor 55, as shown in B of FIG. 21. For example, the projection lens of the transmitting portion 11 is arranged in the opening 56 of the hollow motor 55. Of course, the projector body can also be accommodated therein. This can improve the efficiency of the use of space and can provide a small-sized image display device 100.

[0341] For example, a brushless DC motor, an AC servo motor, or a stepper motor may be used as the hollow motor 55. In addition, when the hollow motor 55 is used, no local force is applied when the screen 12 is rotated. This can substantially reduce the noise caused by the rotation. In addition, the screen 12 and the hollow motor 55 can be directly fixed to each other by the rotating mechanism 17. Compared with rotating the screen 12 using a mechanical component, this can improve reliability.

[0342] Note that the rotating mechanism 14 may be formed without using the hollow motor 55 .

[0343] For example, a configuration in which the rotating mechanism 17 and the screen 12a are rotated by a belt and a gear connected to a motor 57 may be used, as shown in C of FIG. 21. In this case, a motor 57 having a typical rotating shaft may be used, and this can reduce the cost of the device. Any motor having a rotating shaft (such as a brushless DC motor, an AC servo motor, or a stepping motor) may be used as the motor 57.

[0344] 22 and 23 schematically show configuration examples of a rotational shake suppression mechanism.

[0345] Fig. 22A schematically shows an example of adding a weight 58 for adjusting eccentricity to reduce the shaking caused by rotation. In this case, the screen 12 rotates, and the weight 58 is arranged so that the vibration of the screen 12 becomes weak. For example, this rotation calibration is performed on each device when shipped from the factory.

[0346] In B of FIG. 22 , a ball screw 61 including a bearing ball is provided to rotate the shake suppression mechanism 60 to stabilize the upper portion of the side surface of the screen 12. Here, the ball screw 61 is provided at two locations on the left and right. However, the ball screw 61 is generally provided at least at three locations. For example, each ball screw 61 is arranged on the cover portion 15 together with the reflector 13. This can reduce the lateral shake caused in the upper portion of the screen 12.

[0347] In C of Fig. 22, a hollow cap 62 including a plurality of bearings is provided as a shake suppression mechanism 60 to stabilize the upper end of the screen 12. The hollow cap 62 can be fitted to the upper end of the screen 12, and the bearing mechanism is arranged in a portion of the hollow cap 62 that contacts the screen 12. In addition, the hollow cap 62 is a member that is circular as a whole, and is hollow in the center portion.

[0348] For example, the reflector 13 and the hollow cap 62 are fixed to the top surface of the cover portion 15. The image light 1 emitted from the emission portion 11 passes through the hollow portion of the hollow cap 62 to be incident on the reflector 13, and the image light 1 reflected off the reflector 13 passes through the hollow portion of the hollow cap 62 again to be incident on the screen 12.

[0349] The use of such a hollow cap 62 can stabilize the upper portion of the screen 12, thereby substantially reducing the shaking caused by the rotation.

[0350] In A of FIG. 23 , a single ball screw 61 is provided at the center portion of the top surface of the hood portion 15 (the intersection of the hood portion 15 and the optical axis O) as the rotational shake suppression mechanism 60. In this configuration, the reflector 13 is connected to the upper end of the screen 12, and the ball screw 61 stabilizes the side of the reflector 13 opposite to the reflective surface. When the screen 12 is stabilized at a position corresponding to the rotation axis (optical axis O), as described above, even with a small number of ball screws 61, the shake of the screen 12 caused by rotation can be effectively reduced. In addition, since there are fewer ball screws 61, noise can be reduced.

[0351] In B of Fig. 23, a single ball screw 61 is provided at the central portion of the reflective mirror 13 fixed to the top surface of the cover portion 15 (the intersection of the reflective mirror 13 and the optical axis O) as the rotational shake suppression mechanism 60. In this case, the screen 12 is provided with a member that can receive the ball screw 61, such as a light-transmitting top surface part.

[0352] For example, the image light 1 passing through the optical path close to the optical axis O is generally not used for image display. Therefore, when the ball screw 61 is disposed at the central portion of the reflector 13, the image display is not greatly affected. Such a configuration can also stabilize the screen 12 at a position corresponding to the rotation axis (optical axis O), and thus sufficiently reduce the displacement of the screen 12 caused by the rotation.

[0353] Fig. 24 schematically shows a configuration example of a reflection suppressing member. A and B of Fig. 24 schematically show a configuration example of a reflection suppressing member 64 for reducing reflection of the image light 1 emitted by the emission section 11.

[0354] In A of FIG. 24 , a circular reflection suppressing member 64 a whose center portion is opened is arranged at the lower end of the screen 12. This member is a member that rotates together with the screen 12, and may be, for example, the rotating mechanism 17 described with reference to FIG. 1 or a member attached to the rotating mechanism 17. For example, a member formed by bonding a reflection suppressing film to a black substrate or a member to which a reflection suppressing coating is applied may be used as the reflection suppressing member 64 a. As shown in A of FIG. 24 , the image light 1 reflected from the inside of the screen 12 is incident on the reflection suppressing member 64 a. By making such image light 1 less noticeable, the noise of the reflected light can be reduced.

[0355] In B of FIG. 24 , a circular reflection suppressing member 64 b having a diameter larger than that of the cover portion 15 is attached to the lower end of the cover portion 15. This member is fixed to the cover portion 15 and does not rotate. As in the case of the reflection suppressing member 64 a, the reflection suppressing member 64 b is formed using, for example, a reflection suppressing film or a reflection suppressing coating. For example, image light 1 (0-order light) passing through the screen 12 is incident on the reflection suppressing member 64 b as shown in B of FIG. 24 . By making such image light 1 less noticeable, the noise of the reflected light can be reduced.

[0356] Fig. 25 schematically shows a configuration example of the transmitting section 11. A to C of Fig. 25 schematically show a projector main body 41 and various optical systems in the transmitting section 11, respectively.

[0357] In A of Fig. 25, the emitting section 11 includes a projector body 41 that emits the image light 1 and a reflector 47, and the image light 1 emitted by the projector body 41 is reflected by the reflector 47. Generally, the reflector 47 is a plane mirror. The reflector 47 is arranged below the screen 12, and changes the direction of the image light 1 emitted by the projector body 41 that is similarly arranged below the screen 12.

[0358] 25A , the image light 1 emitted horizontally is reflected vertically. The image light 1 reflected from the reflection mirror 47 is incident on the reflection mirror 13 (not shown) provided above the screen 12 , and is reflected from the reflection mirror 13 to be incident on the screen 12 .

[0359] As described above, the position and orientation of the projector body 41 can be changed by using the reflection mirror 47. For example, in A of Fig. 25, the projector body 41 is arranged in a laterally elongated state. This can make the device (eg, base) thinner.

[0360] In B of FIG. 25 , the emission section 11 (projector body 41) is arranged above the screen 12. In this case, the image light 1 emitted by the projector body 41 passes through the inner side of the screen 12 to be incident on the reflection mirror 13 (not shown) arranged below the screen 12, and is reflected from the reflection mirror 13 to be incident on the screen 12.

[0361] As described above, the emitting section 11 can be arranged not only below the screen 12 but also above the screen 12. Even when the image display device 100 is arranged on the ceiling, for example, the screen 12 can be directed toward the audience. This can improve the degree of freedom of placement.

[0362] In C of Fig. 25, the emission section 11 is formed using two projector bodies 41a and 41b and a beam splitter 48 (BS) that combines a plurality of image lights 1 emitted respectively by the two projector bodies 41a and 41b. The beam splitter 48 may be formed using, for example, a prism, or a semi-transparent mirror or the like may be used for the beam splitter 48.

[0363] The beam splitter 48 tilted at an angle of 45 degrees is arranged on the optical axis O below the screen 12. The projector body 41b emits the image light 1 from below to the beam splitter 48 along the optical axis O. In addition, the projector body 41a emits the image light 1 laterally to the beam splitter 48. Therefore, the plurality of image lights 1 emitted by the projector bodies 41a and 41b are combined by the beam splitter 48 to be emitted along the optical axis O. This can improve the brightness of the image displayed on the screen 12.

[0364] As described above, in the image display device 100 according to the present embodiment, the image light 1 emitted by the emission section 11 along the optical axis O is incident on the screen 12 through the reflector 13, and the screen 12 is arranged to completely surround the optical axis O. The screen 12 is provided with an angle controller 22, which emits the image light 1 in different directions for each area and / or each position where the image light is incident on the screen 12. The position and timing at which the image light 1 is incident on the screen 12 are controlled. Switching between the image lights 1 is appropriately performed to emit the image light 1. In this way, an image can be displayed to each viewpoint P. Therefore, the central portion including the specific axis is hollow, and the small-sized image display device 100 can perform high-quality stereoscopic display.

[0365] For example, an image is projected from an emitting section 11 used as a high-speed projector onto a reflector 13 including an angle control function, and image light 1 reflected off the reflector 13 is incident on a screen 12. The image (image light 1) projected onto the screen 12 is divided into vertically extending linear images, and the linear images obtained by the division are horizontally emitted in different directions. The screen 12 is rotated at high speed using a hollow rotating mechanism 14, so as to be synchronized with the image projected by the emitting section 11. In this way, a large number of viewpoints P can be generated around the entire screen 12 within a range of 360 degrees. In this way, a 3D image can be observed with the naked eye from all directions, wherein the 3D image has binocular parallax and motion parallax. In this way, a practical transparent 360-degree 3D display without glasses can be provided.

[0366] Furthermore, in the image display device 100, the emitting portion 11 serving as a high-speed projector and the hollow rotating mechanism 14 are arranged on the same side when viewed from the screen 12. Furthermore, the reflecting mirror 13 is arranged across the screen 12 when viewed from the emitting portion 11 and the rotating mechanism 14. Furthermore, the rotating axis of the rotating mechanism 14 coincides with the optical axis O of the emitting portion 11.

[0367] When a projection system is provided in which the optical axis O coincides with the rotation axis, as described above, the size of the device can be made smaller. In addition, the space formed by the hollow rotation mechanism 14 can be used to arrange the emitting section 11. This enables the emitting section 11 to be closer to the cylindrical screen. Therefore, by making the projection distance smaller, the size of the main body can be made significantly smaller.

[0368] The above configuration is important for miniaturizing the size of the base that accommodates the transmitting portion 11 and the rotating mechanism 14. On the other hand, the screen 12 can also be designed to be relatively large in size. In the image display device 100, as described above, the screen 12 is large relative to the size of the main body. Therefore, the size of the video becomes larger. In addition, there is no structure in the screen 12. This makes it possible to perform a highly transparent stereoscopic display with high image quality. In addition, since the screen 12 is hollow, light projected at an angle close to the optical axis O can also be used to perform image display. This makes it possible to display a large video with high resolution. In addition, since a larger area can be used to perform image display, the efficiency of using the image light 1 can be fully improved.

[0369] Furthermore, the image display device 100 is configured such that the video emitted by the emission section 11 is reflected by the reflection mirror 13 disposed above and displayed. Therefore, the video source is not visible to the viewer 2. This allows clear video display.

[0370] In addition, it is also possible to use only a single HOE to form the screen 12. This can improve the efficiency of using the image light 1 compared to the case where a plurality of HOEs overlap.

[0371] Furthermore, full 360-degree circular display can be performed using a single transmitting section 11 (high-speed projector), thereby reducing the cost of the equipment.

[0372] <Second Embodiment>

[0373] An image display device according to a second embodiment of the present technology is described below. In the following description, descriptions of configurations and operations similar to those of the image display device 100 described in the above embodiment are omitted or simplified.

[0374] An example using a cylindrical screen has been mainly described in the above embodiment. However, the shape of the screen 12 is not limited. In the present embodiment, the screen 12 having a shape other than a cylindrical shape is described.

[0375] FIG. 26 schematically shows a configuration example of an image display device according to the second embodiment.

[0376] A, B, C, and D of FIG. 26 schematically illustrate an image display device 200, an image display device 201, an image display device 202, and an image display device 203, respectively, which each include a screen 12 having a shape other than a cylindrical shape.

[0377] A semi-cylindrical screen 12c is used in the image display device 200 shown in A of FIG. 26. For example, the emitting section 11 is arranged below the screen 12c, and the reflector 13 (not shown) is arranged above the screen 12c. As described above, even if the screen 12c has a semi-cylindrical shape, the screen 12c rotates around the central axis of the cylinder. In this way, stereoscopic display can be performed in all directions covering the entire 360-degree circumference.

[0378] In the image display device 201 shown in B of FIG. 26 , a truncated cone-shaped screen 12 d that widens downward is used. For example, the emitting section 11 is arranged below the screen 12 d, and the reflector 13 (not shown) is arranged above the screen 12 d. Note that when the screen 12 d is used, a lens (such as a wide-angle conversion lens) may be used instead of the reflector 13 to control the incident angle of the image light 1 emitted from the emitting section 11 on the screen 12 d. In this case, the lens through which the image light 1 passes serves as an optical section that controls the incident angle of the image light on the irradiation target.

[0379] In the image display device 202 shown in C of FIG. 26 , a truncated cone-shaped screen 12 e that becomes wider upward is used.

[0380] In the image display device 203 shown in D of FIG. 26 , a screen 12f of a semi-truncated cone shape is used. The semi-truncated cone shape is obtained by cutting a truncated cone that widens downward along a plane including the central axis of the truncated cone. Of course, a semi-truncated cone-shaped screen that widens upward can also be used, which can be obtained by cutting a truncated cone that widens upward along a plane including the central axis of the truncated cone. In this case, the screen 12f rotates around the central axis of the truncated cone, as in the case of A of FIG. 26 . In this way, stereoscopic display can be performed in all directions covering the entire 360-degree circumference.

[0381] As described above, the side of the screen displaying the viewpoint image 30 is preferably a curved surface obtained by rotating around the rotation axis of the screen. This allows the viewpoint image 30 to be displayed at the same position when the screen is rotated, and thus the discomfort of stereoscopic display is less. In addition, the shape of the screen 12 is not limited and can be arbitrarily set according to the application or design of the image display device.

[0382] <Third Embodiment>

[0383] In the above embodiment, the example in which a single angle controller 22 is provided in the screen 12 has been mainly described. However, the number of angle controllers 22 provided in the screen 12 is not limited. In the present embodiment, the screen 12 includes a plurality of angle controllers 22.

[0384] FIG. 27 schematically shows a configuration example of the screen 12 according to the third embodiment.

[0385] A and B of FIG. 27 are schematic plan views of the screens 12g and 12h in a horizontal plane, and the screens 12g and 12h include a plurality of angle controllers 22, respectively.

[0386] In the present embodiment, the angle controller 22 is a convergence angle controller 22 that converges the image light 1 emitted from the plurality of divided areas 23 at the convergence position F. Therefore, one angle controller 22 can simultaneously display the entire viewpoint image 30. By providing a plurality of such angle controllers 22, a plurality of viewpoint images 30 can be simultaneously displayed on one screen 12. In other words, a plurality of viewpoints P (the number of viewpoints generated simultaneously) can be generated in this way, and image display can be performed to the plurality of viewpoints P at the same time.

[0387] The screen 12g shown in A of Fig. 27 is provided with three angle controllers 22. Here, the angle controllers 22 having the same circumferential width are arranged at an azimuth interval of 120 degrees around the optical axis O. Each angle controller 22 has a width less than or equal to 1 / 3 of the length of the outer peripheral surface of the screen 12, and the angle controllers 22 adjacent to each other do not overlap each other.

[0388] Such a configuration makes it possible to display three viewpoint images 30 simultaneously on the screen 12g, and the number of viewpoints generated simultaneously is three.

[0389] The screen 12h shown in B of Fig. 27 is provided with six angle controllers 22. Here, the angle controllers 22 having the same circumferential width are arranged at azimuth intervals of 60 degrees around the optical axis O. Each angle controller 22 has a width less than or equal to 1 / 6 of the length of the outer peripheral surface of the screen 12, and the angle controllers 22 adjacent to each other do not overlap each other.

[0390] Such a configuration makes it possible to display six viewpoint images 30 simultaneously on the screen 12h, and the number of viewpoints generated simultaneously is six.

[0391] In each of the examples shown in A and B of FIG. 27 , angle controllers 22 having the same width are set in one screen 12. This means that the images displayed by the respective angle controllers 22 have equal plane sizes. However, not limited thereto, the angle controllers 22 may also have different sizes. For example, both an angle controller 22 having a large size and an angle controller 22 having a small size may be arranged. In this case, for example, the angle controllers 22 may be selectively used, such as using an angle controller 22 having a large size to display a background, and using an angle controller 22 having a small size to display a character.

[0392] Furthermore, the sizes of the plurality of angle controllers 22 may be arbitrarily set according to, for example, details of the application or content of the device.

[0393] Furthermore, a configuration may also be adopted in which a plurality of angle controllers 22 are formed on one optical film 51 (HOE), or the angle controllers 22 respectively formed on separate optical films 51 are adhered to the screen 12 .

[0394] As described above, the increase in the number of angle controllers 22 enables the viewpoint image 30 to be displayed multiple times to one viewpoint P within one rotation of the screen 12. Therefore, when, for example, the frame rate of a 3D image is constant, the number of rotations of the screen can be reduced due to the presence of a plurality of angle controllers 22. Therefore, switching corresponding to each area set based on the viewpoint interval can be performed slowly, and this can also reduce the frame rate of the projector.

[0395] For the screen 12 including three angle controllers 22, for example, as shown in the above table (1), when the number of viewpoints generated simultaneously is 3, the number of rotations of the screen and the frame rate of the projector are both reduced to 1 / 3 compared to when the number of viewpoints generated simultaneously is 1. Similarly, when the number of viewpoints generated simultaneously is 9, the number of rotations of the screen and the frame rate of the projector are both reduced to 1 / 9.

[0396] In consideration of this relationship, the inventors have studied the minimum frame rate of the projector required for the transmitting section 11, and have found the following conditions under which actual stereoscopic display can be performed.

[0397] First, the frame rate of the 3D image is set to 30fps, the viewpoint spacing is set to 3 degrees, and the number of viewpoints generated simultaneously is set to 9, where the video range is 360 degrees. In this case, the number of rotations of the screen is 200Rpm, and the frame rate of the projector is 240fps. In this case, although the display size is relatively small, the stereoscopic display can be viewed from all directions with a small viewpoint spacing.

[0398] Therefore, the transmitting unit 11 preferably switches between viewpoint images 30 at a projector frame rate of at least 240 fps. When the projector frame rate is 240 fps or more, stereoscopic display can be performed at a larger display size or a higher frame rate can be provided for 3D images.

[0399] In addition, the reduction in the frame rate of the projector (the number of rotations of the screen) causes one viewpoint image 30 to be displayed for a longer period of time. Therefore, a bright viewpoint image 30 can be seen, and the brightness of the stereoscopic display can be improved. Note that when the rotation speed of the screen is not reduced, the number of viewpoint images 30 displayed per unit time increases. This can also improve the brightness.

[0400] FIG. 28 is a schematic diagram for describing a method for adjusting the position of a black stripe area on a screen provided with a plurality of angle controllers.

[0401] In the first embodiment, a method for preventing a reduction in resolution due to the use of a black stripe region (such as the non-diffusion region 24 and the non-display region 38) for reducing crosstalk has been described with reference to FIG. 17. When a plurality of angle controllers 22 are provided, a method for reducing crosstalk using a black stripe region (for example, with reference to FIGS. 11 to 15) is also effective. On the other hand, when a black stripe region is used fixedly, the black stripe region is noticeable. This may result in a low-resolution image with stripes.

[0402] Here, it is assumed that a black stripe region (non-diffusion region 24) is provided in a plurality of angle controllers 22, and a plurality of segmented regions 23 are formed at intervals. In this case, the positions of the non-diffusion regions 24 formed in the respective angle controllers 22 are staggered from each other, and thus a reduction in resolution can be prevented.

[0403] In the example shown in FIG28, three angle controllers 22 (HOE#1, #2, and #3 in the figure) are provided, and the positions of the non-diffusion regions 24 on the respective angle controllers 22 are staggered from each other. Here, the state in which the positions of the non-diffusion regions 24 are staggered from each other means that, for example, in the respective angle controllers, the positions of the non-diffusion regions 24 on the respective angle controllers 22 do not overlap with each other.

[0404] FIG. 28 schematically shows the screen 12 shifted by a 1 / 3 screen rotation period at times t1, t2, and t3.

[0405] For example, at time t1, a viewpoint image 30 is displayed in which the segmented area 23 is located at the center portion of the projection range 36 (the image display is switched to ON). In addition, at time t2, a viewpoint image 30 is displayed in which the segmented area 23 contacts the right boundary of the projection range 36. In addition, at time t3, a viewpoint image 30 is displayed in which the segmented area 23 contacts the left boundary of the projection range 36. As described above, there is a change in the relative position of the segmented area 23 in the projection range 36 relative to the three angle controllers 22. As a result, as shown in the lower part of FIG. 28, images at times t1, t2, and t3 are sequentially displayed in each projection range 36. This makes it possible to display an image with a small overall brightness change in the entire area in the projection range 36 with high resolution.

[0406] As described above, when the number of viewpoints generated simultaneously is at least two, the positions of the segmented regions 23 (non-diffusion regions 24) separated from each other by the gaps are offset from each other. This enables the displayed images to complement each other.

[0407] <Fourth Embodiment>

[0408] In the above embodiment, the screen 12 using the image light 1 of one color has been mainly described. However, it is not limited thereto, and the screen 12 performing color display may also be used.

[0409] For example, the HOE included in the screen 12 is generally an optical element having excellent wavelength selection characteristics, and becomes transparent to light having wavelengths other than the associated wavelength. Therefore, a plurality of angle controllers 22 corresponding to red, green, and blue are provided, respectively. In this way, the viewpoint images 30 of red, green, and blue can be displayed continuously in a time-division manner. In this way, color display can be performed using the residual images of the viewpoint images 30 of red, green, and blue.

[0410] In the present embodiment, the screen 12 is provided with a plurality of angle controllers 22, and the plurality of angle controllers include an angle controller 22R corresponding to red light, an angle controller 22G corresponding to green light, and an angle controller 22B corresponding to blue light. The regions of the angle controllers 22R, 22G, and 22B are generally regions having the same shape and the same size. Note that the angle controllers 22R, 22G, and 22B may also be regions having different shapes and different sizes.

[0411] FIG29 schematically shows an example of a configuration of a screen for color display according to the fourth embodiment. A and C of FIG29 are schematic plan views of respective screens 12i and 12j in a horizontal plane, and the screens 12i and 12j each include angle controllers 22R, 22G, and 22B corresponding to respective colors of red, green, and blue. Note that B of FIG29 is a schematic expansion view of the screen 12i shown in A of FIG29, and schematically shows emission vectors from the angle controllers 22R, 22G, and 22B.

[0412] The screens 12i and 12j each include an angle controller 22 of a convergence type, and are screens obtained by providing colors to the screens 12g and 12h described with reference to FIG. 27, respectively.

[0413] The screen 12i shown in A and B of Fig. 29 is provided with three angle controllers 22R, 22G and 22B. Here, the angle controllers 22 having the same circumferential width are arranged at an azimuth interval of 120 degrees around the optical axis O. In addition, each angle controller 22 has a width less than or equal to 1 / 3 of the length of the outer peripheral surface of the screen 12, and the angle controllers 22 adjacent to each other do not overlap each other.

[0414] A of Fig. 29 shows an angle controller 22R corresponding to red light in the upper left part of the figure, an angle controller 22G corresponding to green light in the lower part of the figure, and an angle controller 22B corresponding to blue light in the upper right part of the figure. Such a configuration enables the screen 12i to simultaneously display viewpoint images 30R, 30G, and 30B corresponding to each color in RGB.

[0415] Furthermore, the rotation of the screen 12i makes it possible to continuously display the viewpoint images 30R, 30G, and 30B in a time-division manner to a single viewpoint P. Therefore, the viewpoint image 30 displayed in full color can be displayed to an arbitrary viewpoint P within one rotation of the screen 12i. Therefore, for the viewpoint image 30 displayed in full color on the screen 12i, the number of viewpoints generated simultaneously is equal to one.

[0416] The screen 12j shown in C of Fig. 29 is provided with a total of six angle controllers, namely, two angle controllers 22R, two angle controllers 22G, and two angle controllers 22B. Here, the angle controllers 22 having the same circumferential width are arranged at an azimuth interval of 60 degrees around the optical axis O. In addition, each angle controller 22 has a width less than or equal to 1 / 6 of the length of the outer peripheral surface of the screen 12, and the angle controllers 22 adjacent to each other do not overlap each other.

[0417] Figure 29C shows an angle controller 22R corresponding to red light in the upper left and lower right parts of the figure, an angle controller 22G corresponding to green light in the upper and lower parts of the figure, and an angle controller 22B corresponding to blue light in the upper right and lower left parts of the figure. Such a configuration enables the screen 12j to simultaneously display viewpoint images 30R, 30G, and 30B corresponding to each color in RGB facing in opposite directions.

[0418] Furthermore, within one rotation of the screen 12j, the full-color viewpoint image 30 can be displayed twice to an arbitrary viewpoint P. Therefore, for the viewpoint image 30 displayed in full color on the screen 12j, the number of viewpoints generated simultaneously is equal to two.

[0419] In addition, the order of arranging the three angle controllers 22R, 22G and 22B is not limited. The usable order includes: a discontinuous order of the same color such as RGBRGB as shown in C of Figure 29, for example, "red, green, blue, red, green, blue", or a continuous order of the same color such as RRGGBB.

[0420] Here, the configuration of the emitting section 11 that projects the viewpoint images 30R, 30G, and 30B of RGB is described. The above mainly describes an example in which the emitting section 11 projects the viewpoint images 30R, 30G, and 30B of RGB, respectively. For example, the emitting section 11 is implemented to include three light sources that respectively emit the respective color lights of RGB, and three light modulators that respectively correspond to the respective color lights of RGB, and the image light 1 of RGB modulated by the corresponding light modulators is emitted along a common optical axis.

[0421] However, the configuration of the emitting section 11 is not limited to the above configuration in which a light source and a light modulator are provided for each color of RGB.

[0422] The emitting section 11 may also include a white light source that emits white light. In this case, the emitting section 11 may be a projector including a single light modulator that modulates white light. Furthermore, the viewpoint images 30R, 30G, and 30B are, for example, grayscale images in which grayscale is set for each pixel.

[0423] As described above, the HOE included in the screen (screens 12i and 12j in FIG. 29 ) has a wavelength selection characteristic, which can selectively diffract light of a specific wavelength and transmit light of wavelengths other than the specific wavelength through the HOE. In other words, the HOE only diffracts light corresponding to one color, just like a color filter. Therefore, when a grayscale image is projected onto the angle controller 22R corresponding to red light, the red light is selectively diffracted and a red image can be displayed. Similarly, when a grayscale image is projected onto the angle controller 22G corresponding to green light, a green image is displayed, and when the grayscale image is projected onto the angle controller 22B corresponding to blue light, a blue image is displayed.

[0424] As described above, color display can be easily performed using a white light source using the wavelength selection characteristics of the HOE. In addition, when a white light source is used, there is no need to provide an RGB light source. This can make the size of the emitting unit 11 smaller and reduce the cost of the emitting unit 11. In addition, it is sufficient to provide only a single light modulator in the above configuration. This can substantially reduce the cost of the device. Note that the light from the white light source can be divided into RGB color lights, and three light modulators corresponding to the respective color lights can be provided. As described above, the use of a white light source makes it possible to share the light source, thereby reducing the cost of the device.

[0425] FIG30 schematically shows another configuration example of a screen for color display. In the screen 12k shown in A of FIG30, the segmented areas 23 corresponding to RGB are arranged continuously at the same angle. In other words, the segmented areas 23R of red light, the segmented areas 23G of green light, and the segmented areas 23B of blue light are arranged adjacently. Therefore, angle controllers 22R, 22G, and 22B corresponding to a plurality of lights of various colors are formed on the entire peripheral surface of the screen 12 so that the respective segmented areas are positioned to be offset from each other.

[0426] Fig. 30A is a schematic plan view of the screen 12k in a horizontal plane. Fig. 30B is a schematic expanded view of the screen 12k shown in Fig. 30A, and schematically shows emission vectors from the angle controllers 22R, 22G, and 22B.

[0427] A transmission vector is set for each position, and is set to converge at a specific convergence position, as shown in the expanded view in B of FIG. 30 .

[0428] For example, the rotation of the screen 12k makes it possible to sequentially display the viewpoint images 30R, 30G, and 30B in the form of divided stripes from one side. Therefore, within one rotation of the screen 12k, the viewpoint image 30 displayed in full color can be displayed in a time-division manner to an arbitrary viewpoint P. Therefore, for the viewpoint image 30 displayed in full color on the screen 12k, the number of viewpoints generated simultaneously is equal to one.

[0429] When the segmented areas 23R, 23G, and 23B corresponding to RGB are arranged continuously at the same angle, as described above, the crosstalk associated with the plurality of color lights of a single viewpoint P can be reduced. In other words, it is not easy to mix with the color light of another viewpoint. Note that, advantageously, a gap (non-diffusion area 24) is also provided between the segmented areas 23R, 23G, and 23B arranged continuously. This can appropriately maintain the ratio of the color light of RGB for each viewpoint, thereby displaying a clear color image.

[0430] In addition, the method of providing the screen 12 for color display is not limited. For example, a film forming only red HOE, a film forming only green HOE, and a film forming only blue HOE may be arranged in a stacked manner to form the screen 12. In this case, the respective segmented areas corresponding to RGB may overlap with each other. By arranging the films corresponding to the respective colors in a stacked manner, the display range of the display viewpoint image can be set larger.

[0431] <Other Implementation Methods>

[0432] The present technical content is not limited to the above-mentioned embodiments, and various other embodiments can be implemented.

[0433] FIG31 schematically shows a configuration example of the transmitting unit 11 and a configuration example of image data according to another embodiment. The configuration in which the viewpoint image 30 is displayed on the screen 12 in all directions has been mainly described in the above embodiment. For example, when the screen 12 is viewed only from one direction or at a determined position, it is not necessary to display the viewpoint image 30 in all directions. In this case, image display can be performed only within a partial angle range on the screen 12.

[0434] A of FIG. 31 shows an example of limiting the display range 26 for displaying the viewpoint image 30 by bringing the display pixels close to each other. Here, the viewpoint image 30 is displayed toward the display range 26 in the lower part of the figure of the screen 12. In this case, the viewpoint image 30 projected by the emission section 11 (not shown) onto the reflector 13 represented by the dotted line area is not necessarily an image formed around the optical axis O, and it is also possible to set it so that the image light 1 can be projected onto the display range 26 on the screen 12, as shown in A of FIG. 31. Here, the image is constructed by maximizing the circular sector-shaped viewpoint image 30 to be displayed in the display range 26 in the frame 32 (display area in the image data 31), and the obtained image is emitted toward the reflector 13.

[0435] When projecting the viewpoint image 30, the emission axis performed by the emission section 11 deviates from the optical axis O so that the image is, for example, closer to one side of the screen 12. Specifically, there is a method of moving the emission axis using a projection lens (e.g., DMD) in an optical modulator (modulation panel). In this case, for example, the above-mentioned reflector 13 having a rotating reflective surface can still be used. In addition, when emitting the viewpoint image 30 with the optical axis O as the center, a free-form surface mirror can also be used to make the display pixel closer to one side of the screen 12.

[0436] In A of Fig. 31, as described above, the viewpoint image 30 for the limited display range 26 in the frame can be maximized. This can improve the resolution of the image display performed on the screen 12.

[0437] In addition, when the image is displayed in full color, it can be achieved by the time-division driving of RGB described above and by the configuration of the HOE for each color. For example, when an angle controller 22 is provided to divide the entire circumference of the screen 12 into three equal parts, as shown in A of FIG. 31, the angle controllers 22 are respectively an angle controller 22R corresponding to red light, an angle controller 22G corresponding to green light, and an angle controller 22B corresponding to blue light. In addition, the viewpoint images 30R, 30G, and 30B corresponding to the respective colors of RGB are respectively projected from the emitting section 11 in a time-division manner onto the angle controllers 22R, 22G, and 22B in a state of deviation from the optical axis O. In this way, full-color stereoscopic display can be performed at a high resolution.

[0438] In B of Fig. 31, the emitting section 11 including a plurality of projector units (projector main bodies) emits a viewpoint image 30. The projector unit is configured to be capable of performing time-division driving for projecting the viewpoint image 30 in a time-division manner. A plurality of such projector units deviating from the optical axis O in different directions are arranged for a single projection lens, and this can increase the angular range for performing display at a high resolution.

[0439] Here, two projector units and a projection lens that causes the viewpoint image 30 emitted from each projector unit to deviate from the optical axis O are provided. The viewpoint image 30a is projected onto the irradiation range (frame 32a) of one projector unit, and the viewpoint image 30b is projected onto the irradiation range (frame 32b) of the other projector unit. In addition, the frame 32a is shifted to cover the half of the upper part of the reflector 13 in the figure, and the frame 32b is shifted to cover the half of the lower part of the reflector 13 in the figure. In addition, in the plan view, the frame 32a and the frame 32b are each set to be circumscribed to a semicircle corresponding to half of the reflector 13. In this way, display can be performed with high resolution around the screen 12.

[0440] Note that the frame 32a (frame 32b) does not necessarily have to be circumscribed to a semicircle corresponding to half of the reflecting mirror 13. For example, the frame 32a (frame 32b) may be set to partially cover the semicircle as shown in A of FIG31. In addition, the frame 32a and the frame 32b may overlap each other, or the size thereof may be larger than that shown in B of FIG31.

[0441] FIG31C shows an example of an optical system that deforms a rectangular frame into a fan shape. It is assumed here that the emitting section 11 is provided with a projection optical system (such as a projection lens). FIG31C shows a rectangular viewpoint image 30 incident on the projection optical system at the top. FIG31C shows a viewpoint image 30 deformed by the projection optical system at the bottom. As described above, by deforming the image in advance by the projection optical system, the resolution difference between the upper and lower parts of the screen 12 can be eliminated when the image is projected onto the screen 12.

[0442] FIG32 schematically shows a configuration example of a screen according to another embodiment. FIG32 shows a group of screens 12 using HOEs. Here, FIG32 shows a group of screens 12 using a transmissive HOE 20 ((1) to (4)), a set of groups 12 using a reflective HOE 21 ((5) to (8)), and a mixed group of screens 12 using both HOEs ((9) to (12)).

[0443] In addition, FIG32 shows the converging screen 12 and the diverging screen 12 included in each of the group using the transmissive HOE 20 and the group using the reflective HOE 21. Note that the HOEs in the two groups each contain a diffusion function. In addition, FIG32 shows the converging screen 12 using the reflective HOE 21 and the converging screen 12 using the transmissive HOE 20 included in the hybrid group.

[0444] The screen 121 in (1) of Fig. 32 converges the image light 1 at the convergence position F using the transmissive HOE 20. The screen 121 is the same type of screen as the screen 12 described with reference to, for example, Fig. 2, and is a screen 12 that can display the entire viewpoint image 30 at the same time.

[0445] The screens 12m, 12n, and 12o in (2), (3), and (4) of FIG. 32 use the transmissive HOE 20 to diverge the image light 1. As described later, the viewpoint image 30 can be displayed in a time-division manner even on the divergent screen 12. In a state where the screen 12 is stationary, the side thereof that emits the image light 1 is hereinafter referred to as the front surface side of the screen 12, and the opposite side is hereinafter referred to as the rear surface side of the screen 12. The front surface of each screen 12 shown in FIG. 32 is located on the lower side in the figure, and the rear surface of each screen 12 shown in FIG. 32 is located on the upper side in the figure.

[0446] The screens 12m, 12n, and 12o are respectively provided with angle controllers 22 of the same size on the respective front surface sides. In addition, for the screen 12m, a starting point position G corresponding to a starting point from which the image light 1 diverges is set on the rear surface side of the screen 12m. For the screen 12n, the starting point position G is set on a portion of the screen 12n located on the rear surface side of the screen 12n. For the screen 12o, the starting point position G is set inside the screen 12o. In addition, if the starting point position G is closer to the center of the screen 12, the angle range of the image light 1 extending around the starting point position G is larger.

[0447] The screens 12p, 12q, and 12r in (5), (6), and (7) of FIG. 32 use a reflective HOE 21 to converge the image light 1. The screens 12p, 12q, and 12r are respectively provided with angle controllers 22 of the same size on their respective back sides. These angle controllers 22 are reflective angle controllers, and each angle controller 22 controls the reflection direction of the incident light when the incident light is reflected from the angle controller 22. In addition, for the screen 12p, the convergence position F for converging the image light 1 is set on the front surface side of the screen 12p. For the screen 12q, the convergence position F is set on a portion of the screen 12q located on the front surface side of the screen 12q. For the screen 12r, the convergence position F is set inside the screen 12r. In addition, if the convergence position F is closer to the center of the screen 12, the angle at which the image light 1 is bent from the angle controller 22 toward the convergence position F will be larger.

[0448] The screen 12s in (8) of Fig. 32 uses the reflective HOE 21 to diverge the image light 1, where the starting position G is the starting point of the divergence. Here, the starting position G is set on the rear surface side of the screen 12s, and the image light 1 reflected from the angle controller 22 is still emitted divergently.

[0449] The screens 12t, 12u, and 12v in (9), (10), and (11) of FIG. 32 use the reflective HOE 21 to converge the image light 1. The screens 12t, 12u, and 12v are provided with angle controllers 22 of the same size on their respective front surface sides. In addition, for the screen 12t, the convergence position F for converging the image light 1 is set on the front surface side of the screen 12t. For the screen 12u, the convergence position F is set on the portion of the screen 12u located on the front surface side of the screen 12u. For the screen 12v, the convergence position F is set inside the screen 12v.

[0450] Note that the reflective HOE 21 of the screens 12t, 12u, and 12v does not have a diffusion function. Therefore, a transmissive HOE 20 having an anisotropic diffusion function is provided on the front surface of the screen through which the reflective HOE 21 passes. Therefore, when the screens 12t, 12u, and 12v are used, an image is displayed on the transmissive HOE 20 located on the front surface of the screen 12.

[0451] The screen 12w in (12) of FIG. 32 uses the transmissive HOE 20a to converge the image light 1. The transmissive HOE 20a that converges the image light 1 does not have a diffusion function. Therefore, the transmissive HOE 20b having an anisotropic diffusion function is bonded to the outside of the transmissive HOE 20a. As described above, the use of two transmissive HOEs 20a and 20b can provide the functions of convergence and diffusion.

[0452] Furthermore, a method of forming the screen 12 using the transmissive HOE 20 or the reflective HOE 21 is not limited.

[0453] FIG. 33 is a schematic diagram for describing a method of displaying the viewpoint images 30 using the divergent screen 12 .

[0454] In the present disclosure, emission angles may be respectively set for the plurality of divided areas 23 included in the angle controller 22 so that the image light 1 emitted from each of the plurality of divided areas 23 converges or diverges in a horizontal plane, as described above.

[0455] Here, a method for displaying the viewpoint image 30 is described using the divergent screen 12 m shown in ( 2 ) of FIG. 32 as an example, wherein the screen 12 m uses the transmissive HOE 20 and its emission angle is set so that the image light 1 diverges.

[0456] FIG. 33 schematically shows a state where the screen 12 m is rotated on the left side, in which there are five optical paths of the image light 1 that is transmitted through the screen 12 m and diverges.

[0457] For example, at time t1, the image light 1 passing through the leftmost optical path in the figure passes through the viewpoint P. Similarly, at time t2, t3, t4, and t5, the image light 1 passing through the second optical path, the third optical path, the fourth optical path, and the fifth optical path from the left side in the figure passes through the viewpoint P. As described above, when focusing on a certain viewpoint P, as the screen 12 rotates, each image light 1 emitted and diverged from the corresponding divided area 23 of the angle controller 22 must pass through the viewpoint P once during each rotation of the screen 12.

[0458] FIG33 schematically shows on the right side the optical paths of a plurality of image lights 1 passing through the viewpoint P at times t1 to t5, respectively. When the optical paths of the image lights 1 passing through the viewpoint P overlap, as shown in the figure, the optical paths are similar to the optical paths obtained when the viewpoint images 30 displayed on the screen 12 converge at the viewpoint P (refer to B of FIG2 ). Using such a configuration makes it possible to display the viewpoint images 30 in a time-division manner.

[0459] Specifically, at time t1, in the segmented area 23 passing through the leftmost optical path in the figure, the segmented image 34 corresponding to the segmented area 23 in the viewpoint image 30 corresponding to the viewpoint P is displayed. Furthermore, at time t2, t3, t4, and t5, in the segmented areas corresponding to the second optical path, the third optical path, the fourth optical path, and the fifth optical path from the left in the figure, the segmented images 34 corresponding to the respective segmented areas 23 in the viewpoint image 30 corresponding to the viewpoint P are displayed. In this way, the viewpoint image 30 corresponding to the specific viewpoint P can be displayed in a time-division manner to the specific viewpoint P. As described above, even when the viewpoint image 30 is displayed in a time-division manner, the viewer 2 can perceive the entire viewpoint image 30 using the residual images of the plurality of segmented images 34 (linear video).

[0460] FIG. 34 schematically shows an example of adjusting the diffusion angle by applying a physical slit.

[0461] Here, an example is described in which a physical slit is used for the screen 12 so that the image light 1 can be condensed on the screen 12 , as in the case of ( 6 ) of FIG. 32 .

[0462] The screen 12x shown in Fig. 34 is provided with a reflective HOE 21 on the rear surface side (upper side in the figure) of the screen 12x. The image light 1 reflected from the reflective HOE 21 is first condensed on a portion of the front surface of the screen. Thereafter, the image light 1 is emitted and diverged.

[0463] A physical slit 49 is provided at a converging position located on the front surface side. Here, the physical slit 49 is a longitudinally long slit arranged vertically, in which light passes through the center of the slit and is blocked by parts on both sides of the slit. The provision of the physical slit 49 makes it possible to perform adjustment so that, for example, the distribution of diffused light diffused by the reflective HOE 21 is narrower.

[0464] 34 schematically shows a gray area, which represents the diffusion distribution of the image light 1 emitted from the right end of the reflective HOE 21. The diffusion distribution is wider than the slit width of the physical slit 49. Therefore, in the image light 1 emitted from the right end of the reflective HOE 21, only the component contained therein that can pass through the physical slit 49 can pass through the physical slit 49, and the other components are blocked by the blocking portions on both sides.

[0465] This makes it possible to make the beam width in the horizontal plane narrower. Therefore, even when the manufacturing accuracy of the reflective HOE 21 used as a reflective diffusion screen is low, for example, image display with sufficiently reduced crosstalk can be achieved.

[0466] FIG. 35 schematically shows an example of segmented regions having different angular components in the vertical direction.

[0467] In the above embodiment, an example has been described in which the emission angles are set for the plurality of segmented areas 23 so that the angle components (azimuth components) formed in the horizontal plane are different from each other and the angle components (elevation components) formed with the horizontal plane are fixed. For example, different elevation components may be set for the emission angles, thereby forming a screen 12 in which the emission angle also changes in the up-down direction.

[0468] The strip-shaped divided areas 23 extending longitudinally are provided on the screen 12y shown in A of Fig. 35. Here, the emission angle is set for a set of three continuous divided areas 23.

[0469] For example, all azimuth components of the emission angles set for the three segmented areas included in the set are set to the same value. On the other hand, the elevation components of the emission angles are set to different values. Here, for the three segmented areas in the set, an elevation component T (top) that can be directed obliquely upward relative to the horizontal plane, an elevation component C (center) parallel to the horizontal plane, and an elevation component B (bottom) that can be directed obliquely downward relative to the horizontal plane are set, respectively. In the example shown in A of FIG. 35 , the elevation components B, T, and C are set in order from the left.

[0470] Note that setting may be performed so that the azimuth component of the emission angle differs according to different sets of divided areas. For example, a set of three divided areas is used to provide a converging screen 12y that can converge the image light 1 in a horizontal plane.

[0471] In this way, it can also be said that the screen 12y distributes the video in the horizontal direction to the viewpoint located in the vertical direction for display. In this way, the viewpoint image 30 can be displayed so that the viewpoint image 30 is also oriented toward the viewpoint P viewing the screen 12y from above or below. In this way, motion parallax can be provided in the up and down directions, thereby providing a natural stereoscopic image.

[0472] The screen 12z in B of FIG. 35 is provided with a plurality of divided areas 23 arranged in a grid shape divided in the circumferential direction and the longitudinal direction.

[0473] In this configuration, the azimuth component of the emission angle is different according to different longitudinal extension lines. Therefore, the segmented areas included in the same longitudinal extension line have the same azimuth component of the emission angle, while the segmented areas included in different longitudinal extension lines have different azimuth components.

[0474] In addition, the elevation component of the emission angle is set to change periodically for each laterally extending line. Here, the elevation component of the emission angle is set for each laterally extending line in the order of C, T, B starting from the top of the screen 12z.

[0475] In this way, it can also be said that the screen 12z divides the video in the vertical direction and distributes it to the viewpoints in the vertical direction for display. In this configuration, the viewpoint image 30 can also be displayed as facing the viewpoint P that views the screen 12z from above or below. In addition, compared with the case where the video in the horizontal direction of A of Figure 35 faces different directions, this configuration can increase the resolution in the circumferential direction. In this way, stereoscopic display can be performed with high quality.

[0476] In B of FIG. 35 , the segmented areas 23 are arranged in a grid shape divided by the circumferential direction and the longitudinal direction, wherein different emission angle elevation components are set for the segmented areas 23. However, the configuration is not limited thereto. For example, segmented areas 23 arranged in a staggered pattern or segmented areas 23 arranged in a random pattern slightly staggered from each other may be provided. In this case, the segmented areas 23 are arranged to be slightly staggered from each other. Therefore, brightness unevenness in the interior of the segmented area 23 and in the boundaries of the segmented area 23 is eliminated to provide brightness uniformity. This can improve transparency.

[0477] FIG. 36 schematically shows another example of the screen 12 that changes its emission angle in the up-down direction.

[0478] As shown in A of Fig. 36, three angle controllers 22T, 22C, and 22B are formed on the screen 12. Here, the angle controllers 22 are respectively formed within an angle range of 120 degrees, and there is no gap between the angle controllers 22. However, there may be gaps between the angle controllers 22.

[0479] B of FIG. 36 schematically shows the elevation angle component of the emission angle for emitting the image light 1 incident on the angle controllers 22T, 22C, and 22B. A plurality of segmented areas 23 are formed on the angle controller 22T, and an elevation angle component T oriented obliquely upward relative to the horizontal plane is set for these segmented areas. A plurality of segmented areas 23 are formed on the angle controller 22c, and an elevation angle component C parallel to the horizontal plane is set for these segmented areas. A plurality of segmented areas 23 are formed on the angle controller 22B, and an elevation angle component B oriented obliquely downward relative to the horizontal plane is set for these segmented areas.

[0480] Furthermore, as shown in C of FIG. 36 , the angle controllers 22T, 22C, and 22B are configured to converge the image light 1 incident on each of the divided areas 23 .

[0481] Using the screen 12 shown in FIG. 36 makes it possible to display, for example, a 3D image that can be viewed at three different elevation angles relative to one direction (one viewpoint P). As described above, it is also possible to assign a viewpoint located in the vertical direction to each angle controller 22. In this configuration, it is sufficient to form three angle controllers 22 having different elevation components, respectively. This makes it easy to expose the HOE to light.

[0482] For example, a system for detecting the viewing position (viewpoint P) at which the viewer is viewing can be used to perform stereoscopic display depending on the actual viewpoint of the viewer. For example, a system such as a face tracking sensing system (face tracking) or an eye tracking sensing system (eye tracking) can be introduced to perform sensing on the entire peripheral surface of the screen.

[0483] For example, an omnidirectional camera having, for example, a fisheye lens is provided in the image display device, and the video captured by the omnidirectional camera is appropriately analyzed. In this way, face tracking or line of sight tracking can be performed. Based on the result of the tracking, a 3D object or the like that moves interactively is displayed on the screen according to the current viewpoint P of the viewer. This enables the viewer to watch a natural stereoscopic image associated with his / her own movement.

[0484] Furthermore, a system for detecting the viewing position (viewpoint P) at which the viewer is viewing can be used to reduce the amount of video signal transmission corresponding to the image data 31. In other words, processing such as not displaying images in a direction that the viewer is not viewing can reduce the total amount of data and reduce the processing load required to perform image processing.

[0485] 37 is a schematic diagram for describing viewpoint images viewed as the position of the viewpoint P in the up-down direction changes. When the position of the viewpoint P in the up-down direction changes, a motion parallax video having up-down motion parallax can be displayed in real time.

[0486] In A of FIG. 37 , the same viewpoint image 30 is displayed regardless of the position of the viewpoint P in the up-down direction. Here, as shown on the left side in A of FIG. 37 , the viewpoint image 30 is displayed, which includes the 3D object 7 that appears rectangular when the screen 12 is viewed from the front. Assume that the viewpoint P moves upward in this state, and the screen 12 is viewed from obliquely above, as shown on the right side in A of FIG. 37 . In this case, if the viewpoint image 30 changes, the display position of the 3D object 7 will also shift. This may cause noticeable arc-shaped distortion.

[0487] A method for reducing such a shift and distortion of the display position is to correct the 3D object 7 (viewpoint image 30 ) using a system that detects the viewer's viewpoint P so as to reflect motion parallax in the up-and-down direction.

[0488] 37B , the viewpoint image 30 is corrected according to the position in the up-down direction of the viewpoint P. Here, when viewed from obliquely above, the position and shape of the viewpoint image 30 are corrected in real time so that the 3D object 7 having the correct shape is positioned in the real space.

[0489] For example, when the screen 12 is viewed from above, the 3D object 7 moves upward, and when the screen 12 is viewed from below, the 3D object 7 moves downward. In addition, the 3D object 7 is corrected according to an angle corresponding to the position of the viewpoint P in the up-down direction so that arc-shaped distortion disappears.

[0490] This correction results in that the display position of the 3D object 7 does not change when the screen 12 is viewed from the front (left side in B of FIG. 37 ) and when the screen 12 is viewed from diagonally above (right side in B of FIG. 37 ), and unnatural distortion can also be avoided. This makes it possible to perform a natural stereoscopic display with a sense of reality.

[0491] In the above description, a reflector having a parabolic reflective surface is used. However, the shape of the reflective surface and the like are not limited, and any reflective surface that can reflect image light may be used, for example, according to the shape of the screen. For example, the reflective surface may be an aspherical surface (such as a free surface) other than a parabola. For example, the free surface is configured so that the incident angle of the image light on the screen is substantially constant. Such a curved surface may be designed, for example, according to an optical path simulation.

[0492] In addition, the reflective surface is not limited to being configured so that the incident angle is substantially constant, and the image light can also be reflected off the reflective surface so that the incident angle is distributed within a specific angle range. In this case, for example, the image light is incident on the screen at different incident angles in the up and down directions.

[0493] In addition, the image light can be incident on the screen using, for example, an optical element that refracts the image light instead of using a mirror that reflects the image light. For example, a transmissive optical element such as a Fresnel lens can be used to control the traveling direction of the image light so that the image light is incident on the screen.

[0494] The method for controlling the rotation of the screen performed by the rotation mechanism has been described above as a method for synchronizing the display of the image composed of the image light with the rotation of the screen. For example, the timing of displaying the viewpoint image can be controlled according to the rotation of the screen. In addition, for example, both the timing of displaying the viewpoint image and the rotation of the screen can be controlled so that the viewpoint image is correctly displayed.

[0495] The following are examples of image display devices.

[0496] FIG. 38 is a perspective view showing a configuration example of an image display device.

[0497] FIG39 is a plan view of the image display device shown in FIG38.

[0498] FIG. 40 is a bottom view of the image display device shown in FIG. 38 .

[0499] FIG. 41 is a side view of the image display device shown in FIG. 38 .

[0500] FIG. 42 is a perspective view of a screen unit provided in the image display apparatus shown in FIG. 38 .

[0501] FIG43 is a plan view of the screen unit shown in FIG42.

[0502] FIG. 44 is a side view of the screen unit shown in FIG. 42 .

[0503] The image display device 300 shown in Fig. 38 includes a base 310, a screen 312, a reflector 313, and a cover 315. In addition, a transmitting portion (not shown) and a rotating mechanism (not shown) are provided inside the image display device 300. For example, the base 310, the screen 312, the reflector 313, and the cover 315 respectively have configurations similar to the corresponding configurations of the base 10, the screen 12, the reflector 13, and the cover 15 described above.

[0504] In the image display device 300, the screen unit 320 is formed of a screen 312 and a cover 315. The screen unit 320 is a component that displays an image to a viewer who is viewing the image display device 300, wherein the cylindrical screen 312 and the cylindrical cover 315 are arranged around the same axis. Both ends of the screen 312 are open, and both ends of the cover 315 are open.

[0505] In addition, the screen 312 and the cover 315 are transparent members. The screen 312 is rotated by the rotating mechanism, and the cover 315 is fixed to the base 310 to protect the rotating screen 312. The reflector 313 is fixed to the cover 315 included in the screen unit 320. However, the reflector 313 can also be fixed to the screen 312.

[0506] An example of the size of the image display device 300 (screen unit 320) is described below. The screen 312 has an outer diameter of 100 mm and has a thickness of 2 mm. The cover 315 has an outer diameter of 108 mm and has a thickness of 3 mm. The interval between the screen 312 and the cover 315 is 1 mm. In this case, the screen unit 320 does not look like a double-layer unit because the interval between the screen 312 and the cover 315 is small. This allows the screen 312 and the cover 315 to present a more attractive unified appearance, thereby enhancing the aesthetic appearance of the screen unit 320.

[0507] FIG. 45 is a perspective view showing another configuration example of the screen unit.

[0508] FIG46 is a plan view of the screen unit shown in FIG45 .

[0509] FIG. 47 is a bottom view of the screen unit shown in FIG. 45 .

[0510] FIG48 is a side view of the screen unit shown in FIG45 .

[0511] The screen unit 320a shown in FIG45 is a variation of the screen unit 320 shown in FIG42, in which a cylindrical screen 312a and a cylindrical cover portion 315a are arranged around the same axis to form the screen unit 320a. Both ends of the screen 312a are open, the upper end of the cover portion 315a is closed, and the lower end of the cover portion 315a is open. The cover portion 316a having a circular flat plate shape and covering the upper end of the cover portion 315a may be transparent or opaque.

[0512] FIG. 49 is a perspective view showing another configuration example of the screen unit.

[0513] FIG50 is a plan view of the screen unit shown in FIG49.

[0514] FIG51 is a bottom view of the screen unit shown in FIG49.

[0515] FIG52 is a side view of the screen unit shown in FIG49.

[0516] The screen unit 320b shown in FIG. 49 is a variation of the screen unit 320 shown in FIG. 42, in which a cylindrical screen 312b and a cylindrical cover portion 315b are arranged around the same axis to form the screen unit 320b. The upper end of the screen 312b is closed, the lower end of the screen 312b is open, and both ends of the cover portion 315b are open. For example, when a reflector is fixed to the cover portion 315b, the cover portion 316b having a circular flat plate shape and covering the upper end of the screen 312b is transparent. In addition, for example, when a reflector is fixed to the screen 312b, the cover portion 316b may be opaque.

[0517] FIG. 53 is a perspective view showing another configuration example of the image display device.

[0518] FIG54 is a plan view of the image display device shown in FIG53.

[0519] FIG. 55 is a bottom view of the image display device shown in FIG. 53 .

[0520] FIG56 is a side view of the image display device shown in FIG53.

[0521] FIG57 is a perspective view of a screen unit provided in the image display device shown in FIG53.

[0522] FIG58 is a plan view of the screen unit shown in FIG57 .

[0523] FIG59 is a side view of the screen unit shown in FIG57 .

[0524] The image display device 400 shown in Fig. 53 includes a base 410, a screen 412, a reflector 413, and a cover 415. In addition, a transmitting portion (not shown) and a rotating mechanism (not shown) are provided inside the image display device 400. For example, the base 410, the screen 412, the reflector 413, and the cover 415 respectively have configurations similar to the corresponding configurations of the base 10, the screen 12, the reflector 13, and the cover 15 described above.

[0525] In the image display device 400, the screen unit 420 is formed of a screen 412 and a cover 415. The screen unit 420 is a component that displays an image to a viewer who is viewing the image display device 400, wherein the cylindrical screen 412 and the cylindrical cover 415 are arranged around the same axis. Both ends of the screen 412 are open, and both ends of the cover 415 are open.

[0526] In addition, the screen 412 and the cover 415 are transparent members. The screen 412 is rotated by the rotating mechanism, and the cover 415 is fixed to the base 410 to protect the rotating screen 412. The reflector 413 is fixed to the cover 415 included in the screen unit 420. However, the reflector 413 may also be fixed to the screen 412.

[0527] An example of the size of the image display device 400 (screen unit 420) is described below. The screen 412 has an outer diameter of 200 mm and has a thickness of 3 mm. The cover 415 has an outer diameter of 226 mm and has a thickness of 3 mm. The interval between the screen 412 and the cover 415 is 10 mm. In this case, since the interval between the screen 412 and the cover 415 is large, there is space for the screen 412 to rotate and swing. This makes it easy for the screen 412 to avoid contact with the cover 415, thereby making it easy to manufacture the image display device 400.

[0528] At least two features of the present technology described above can also be combined. In other words, regardless of the implementation, the various features described in each implementation can be combined arbitrarily. In addition, the various effects described above are not restrictive, but merely illustrative, and other effects can be provided.

[0529] In the present disclosure, expressions such as “same”, “equal” and “orthogonal” conceptually include expressions such as “substantially the same”, “substantially equal” and “substantially orthogonal”. For example, a state within a specific range (such as a range of + / -10%) with reference to expressions such as “completely the same”, “completely equal” and “completely orthogonal” is included.

[0530] Note that the present technical content can also adopt the following configurations.

[0531] (1) An image display device comprising:

[0532] an illumination target which is arranged at least partially around a specific axis and is illuminated by the image light, and has at least one angle controller which emits the image light at emission angles different from each other for each region where the image light is incident and / or each position where the image light is incident;

[0533] a rotating mechanism that rotates the irradiation target around the specific axis;

[0534] an emitting section that emits the image light along the specific axis and is capable of switching the image light at intervals shorter than at least a rotation period of the rotating mechanism;

[0535] an optical section that is arranged facing the emitting section with the specific axis as a reference and controls an incident angle of the image light emitted by the emitting section with respect to the irradiation target; and

[0536] A control unit synchronizes display of an image formed by the image light with rotation of the irradiation target.

[0537] (2) The image display device according to (1), wherein

[0538] The angle controller includes a plurality of divided areas which divide the image light incident through the optical portion to emit the image light at emission angles different from each other.

[0539] (3) The image display device according to (2), wherein

[0540] The plurality of divided regions extend along the direction of the specific axis on the irradiation target.

[0541] (4) The image display device according to (2) or (3), wherein

[0542] The emission angles are set for the plurality of divided areas so that angle components in an orthogonal plane orthogonal to the specific axis are different from each other.

[0543] (5) The image display device according to (4), wherein

[0544] The emission angles are set for the plurality of divided areas so that image light emitted from each divided area converges or diverges in the orthogonal plane.

[0545] (6) The image display device according to at least one of (2) to (5), wherein

[0546] The plurality of divided areas are capable of diffusing and emitting the image light at the emission angles set for the respective divided areas, and

[0547] The angle ranges at which the image light is diffused in the plurality of divided areas are such that an angle range formed in an orthogonal plane orthogonal to the specific axis is smaller than an angle range formed with respect to the orthogonal plane.

[0548] (7) The image display device according to at least one of (2) to (6), wherein

[0549] The angle controller includes a non-diffusion area which is formed between the division areas adjacent to each other and does not diffuse the image light.

[0550] (8) The image display device according to at least one of (2) to (7), wherein

[0551] The irradiation target has a plurality of angle controllers as the at least one angle controller.

[0552] (9) The image display device according to (8), wherein

[0553] The plurality of angle controllers include an angle controller for red light, an angle controller for green light, and an angle controller for blue light.

[0554] (10) The image display device according to at least one of (2) to (9), wherein

[0555] The control section synchronizes display of viewpoint images constituted by image light with rotation of the illumination target so that the viewpoint images corresponding to the respective viewpoints can be viewed from a plurality of viewpoints provided around the illumination target.

[0556] (11) The image display device according to (10), wherein

[0557] The plurality of viewpoints are arranged in a ring around the specific axis,

[0558] the angle controller includes a non-diffusion area which is formed between the division areas adjacent to each other and does not diffuse the image light,

[0559] The control unit is configured to turn off the image display achieved by the image light when the boundary of the projection range divided by the angular spacing of the multiple viewpoints overlaps with the divided area, and to turn on the image display achieved by the image light when the boundary of the projection range and the non-diffusion area overlap with each other.

[0560] (12) The image display device according to (10), wherein

[0561] The plurality of viewpoints are arranged in a ring around the specific axis,

[0562] The viewpoint images are images in which a display area where an image is displayed and a non-display area where an image is not displayed are set within an angular interval of the plurality of viewpoints,

[0563] The control section is configured to turn off image display by the image light when the boundary of the divided area and the display area overlap each other, and turn on image display by the image light when the boundary of the divided area and the display area do not overlap each other.

[0564] (13) The image display device according to at least one of (1) to (12), wherein

[0565] The illumination target is a screen using a holographic optical element.

[0566] (14) The image display device according to at least one of (1) to (13), wherein

[0567] The irradiation target has a light-transmitting property.

[0568] (15) The image display device according to at least one of (1) to (14), wherein

[0569] The optical section controls an incident angle of the image light with respect to the irradiation target to be substantially constant.

[0570] (16) The image display device according to at least one of (1) to (15), further comprising:

[0571] A cover portion is arranged around the irradiation target and has a light-transmitting property.

[0572] (17) The image display device according to (16), wherein

[0573] The optical portion is fixed to the cover portion.

[0574] (18) The image display device according to at least one of (1) to (17), wherein

[0575] When viewed from the irradiation target, the emitting portion and the rotating mechanism are arranged on the same side.

[0576] (19) The image display device according to at least one of (1) to (18), wherein

[0577] The rotating mechanism includes a hollow motor rotating around the specific axis, and

[0578] At least a portion of the emitting portion is disposed in the opening of the hollow motor.

[0579] (20) The image display device according to at least one of (1) to (19), wherein

[0580] The irradiation target has a cylindrical shape with the specific axis as a basic central axis.

[0581] Reference numerals

[0582] O optical axis

[0583] P Viewpoint

[0584] 1 Image Light

[0585] 2. Audience

[0586] 11 Transmitter

[0587] 12, 12a to 12z, 312, 312a, 312b, 412 screens

[0588] 13, 313, 413 reflectors

[0589] 14 Rotating mechanism

[0590] 15, 315, 415 hood

[0591] 19 Controller

[0592] 20 Transmissive HOE

[0593] 21 Reflective HOE

[0594] 22, 22R, 22G, 22B angle controller

[0595] 23, 23R, 23G, 23B segmentation area

[0596] 24 Non-diffusion area

[0597] 30 viewpoint images

[0598] 37 Display Area

[0599] 38 Non-display area

[0600] 55 hollow motor

[0601] 100, 200, 201, 202, 203, 300, 400 image display devices

Claims

1. An image display device, comprising: an illumination target which is arranged at least partially around a specific axis and is illuminated by the image light, and has at least one angle controller which emits the image light at emission angles different from each other for each region where the image light is incident and / or each position where the image light is incident; a rotating mechanism that rotates the irradiation target around the specific axis; an emitting section that emits the image light along the specific axis and is capable of switching the image light at intervals shorter than at least a rotation period of the rotating mechanism; an optical section arranged facing the emitting section with the specific axis as a reference, and controlling an incident angle of the image light emitted by the emitting section with respect to the irradiation target; as well as A control unit synchronizes display of an image formed by the image light with rotation of the irradiation target.

2. The image display device according to claim 1, wherein The angle controller includes a plurality of divided areas which divide the image light incident through the optical portion to emit the image light at emission angles different from each other.

3. The image display device according to claim 2, wherein The plurality of divided regions extend along the direction of the specific axis on the irradiation target.

4. The image display device according to claim 2, wherein The emission angles are set for the plurality of divided areas so that angle components in an orthogonal plane orthogonal to the specific axis are different from each other.

5. The image display device according to claim 4, wherein The emission angles are set for the plurality of divided areas so that image light emitted from each divided area converges or diverges in the orthogonal plane.

6. The image display device according to claim 2, wherein The plurality of divided areas are capable of diffusing and emitting the image light at the emission angles set for the respective divided areas, and The angle ranges at which the image light is diffused in the plurality of divided areas are such that an angle range formed in an orthogonal plane orthogonal to the specific axis is smaller than an angle range formed with respect to the orthogonal plane.

7. The image display device according to claim 2, wherein The angle controller includes a non-diffusion area which is formed between the division areas adjacent to each other and does not diffuse the image light.

8. The image display device according to claim 2, wherein The irradiation target has a plurality of angle controllers as the at least one angle controller.

9. The image display device according to claim 8, wherein The plurality of angle controllers include an angle controller for red light, an angle controller for green light, and an angle controller for blue light.

10. The image display device according to claim 2, wherein The control section synchronizes display of viewpoint images constituted by image light with rotation of the illumination target so that the viewpoint images corresponding to the respective viewpoints can be viewed from a plurality of viewpoints provided around the illumination target.

11. The image display device according to claim 10, wherein The plurality of viewpoints are arranged in a ring around the specific axis, the angle controller includes a non-diffusion area which is formed between the division areas adjacent to each other and does not diffuse the image light, The control unit is configured to turn off the image display achieved by the image light when the boundary of the projection range divided by the angular spacing of the multiple viewpoints overlaps with the divided area, and to turn on the image display achieved by the image light when the boundary of the projection range and the non-diffusion area overlap with each other.

12. The image display device according to claim 10, wherein The plurality of viewpoints are arranged in a ring around the specific axis, The viewpoint images are images in which a display area where an image is displayed and a non-display area where an image is not displayed are set within an angular interval of the plurality of viewpoints, The control section is configured to turn off image display by the image light when a boundary of the divided area and the display area overlap each other, and to turn on image display by the image light when the boundary of the divided area and the display area do not overlap each other.

13. The image display device according to claim 1, wherein The illumination target is a screen using a holographic optical element.

14. The image display device according to claim 1, wherein The irradiation target has a light-transmitting property.

15. The image display device according to claim 1, wherein The optical section controls an incident angle of the image light with respect to the irradiation target to be substantially constant.

16. The image display device according to claim 1, further comprising: A cover portion is arranged around the irradiation target and has a light-transmitting property.

17. The image display device according to claim 16, wherein The optical portion is fixed to the cover portion.

18. The image display device according to claim 1, wherein When viewed from the irradiation target, the emitting portion and the rotating mechanism are arranged on the same side.

19. The image display device according to claim 1, wherein The rotating mechanism includes a hollow motor rotating around the specific axis, and At least a portion of the emitting portion is disposed in the opening of the hollow motor.

20. The image display device according to claim 1, wherein The irradiation target has a cylindrical shape with the specific axis as a basic central axis.

Images