Stereoscopic image display device

Abstract

To provide a stereoscopic image display device which enables visual recognition from any direction with less limitations on a visual field angle and enables display of a moving image.SOLUTION: A stereoscopic image display device according to an embodiment comprises: a three-dimensional pixel unit in which a plurality of pixel cells formed of optical materials whose optical characteristics can be electrically changed is three-dimensionally arranged so as to be apart from each other, and the plurality of pixel cells is electrically connected in a transparent wiring pattern; a backlight which emits illumination light to the three-dimensional pixel unit; and an arithmetic / control circuit which individually controls the pixel cells via the wiring pattern on the basis of the input three-dimensional video data and causes the three-dimensional pixel unit to function as a transmission type hologram.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] 1. Field of the Invention The present invention relates to a stereoscopic image display device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, known stereoscopic image display devices include an image display device that displays images from a plurality of viewpoints by combining a flat display with a lenticular lens, and a holographic display device that prints interference fringes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 02-029697 [Patent Document 2] Japanese Patent Application Publication No. 06-233328 [Patent Document 3] JP 2004-226736 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional technology has problems such as the viewpoint being discrete, limiting the viewing angle, and not being able to display moving images.

[0005] The present invention has been made in consideration of the above, and aims to provide a stereoscopic image display device that has few limitations on the viewing angle, can be viewed from any direction, and is also capable of displaying moving images. [Means for solving the problem]

[0006] The stereoscopic image display device according to the embodiment includes: A light reproduction type stereoscopic image display device capable of naked eye stereoscopic viewing,a three-dimensional pixel unit in which a plurality of pixel cells formed of an optical material whose optical characteristics can be electrically changed are arranged in a three-dimensional manner, the plurality of pixel cells are electrically connected to each other by a transparent wiring pattern, a backlight is provided for emitting illumination light to the three-dimensional pixel unit, and the pixel cells are individually controlled via the wiring pattern based on input three-dimensional image data; 3. Arraying pixel cells whose optical characteristics are changed and pixel cells whose optical characteristics are not changed in a three-dimensional manner; The three-dimensional pixel unit Multi-view imaging possible and a calculation / control circuit that causes it to function as a transmission hologram. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic block diagram of a stereoscopic image display system. [Diagram 2] FIG. 2 is a schematic perspective view of an example of the structure of a three-dimensional pixel unit. [Diagram 3] FIG. 3 is an explanatory diagram of a three-dimensional pixel unit. [Figure 4] FIG. 4 is a conceptual explanatory diagram of an example of the configuration of a pixel cell. [Diagram 5] FIG. 5 is a diagram illustrating an example of the relationship between the voltage applied to the optical material layer and the light transmittance. [Figure 6] FIG. 6 is an explanatory diagram of a method for changing the optical characteristics of a pixel cell. [Figure 7] FIG. 7 is a diagram illustrating an example of a control state of a three-dimensional pixel unit. [Figure 8] FIG. 8 is a conceptual explanatory diagram of another configuration example of a pixel cell. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Next, an embodiment will be described with reference to the drawings. FIG. 1 is a schematic block diagram of a stereoscopic image display system. The stereoscopic image display system 10 includes a three-dimensional image information generating device 11, a data converting device 12, an information transmitting device 13, and a three-dimensional image display device 14.

[0009] The three-dimensional image information generating device 11 is equipped with a TOF (Time Of Flight) sensor, etc., and includes an imaging device 11A that captures images of the subject, including the distance to each part of the subject, and outputs the captured image data, and performs calculations based on the captured image data to generate three-dimensional image data for realizing a transmission type volume hologram for displaying three-dimensional images, and outputs the data to a transfer information generating device 12A described below. In this case, if the current 2D image is composed of coordinates (x, y) on the screen and information on color and brightness (collectively referred to as c) at a certain moment, the 3D video information generating device 11 outputs information for reproducing light rays on the screen in the 3D image, assuming that the screen is composed of a group of (x, y, c). More specifically, from a pixel (x,y), color and brightness (c) are shown in the direction of the angle of attack (v) and direction angle (h), and the image at a certain moment is composed of a group of (x,y,v,h,c).In this case, if the rules for the transmission order are determined in advance, it is possible to omit the information (x,y,v,h) and transmit only the information c, such as color and brightness.

[0010] Here, the volume hologram forms interference fringes as a distribution of optical information such as the refractive index, polarization plane, phase, and transmittance inside the material.

[0011] The data conversion device 12 has a transfer information generating device 12A and a storage 12B such as a hard disk drive device, and stores the three-dimensional video data input to the storage 12B. The transfer information generating device 12A uses the storage 12B to convert the three-dimensional video data into a format that can be transferred via a communication network or broadcast waves, and outputs the three-dimensional video data for transfer to the information transmitting device 13.

[0012] The information transmitting device 13 is configured as a server that distributes the transfer 3D video data to the 3D video display device via a communication network, or as a broadcasting device that transmits the transfer 3D video data to the 3D video display device via broadcast waves.

[0013] The three-dimensional image display device 14 comprises a receiving device 14A that receives three-dimensional image data to be transferred from the information transmitting device 13, an arithmetic / control circuit 14B that performs arithmetic processing on the received three-dimensional image data to be transferred, calculates a three-dimensional pixel pattern, and controls the entire three-dimensional image display device, a display panel 14C having a three-dimensional structure that functions as a transmissive volume hologram based on the three-dimensional image data under the control of the arithmetic / control circuit 14B, and a backlight 14D that irradiates illumination light from behind the display panel 14C under the control of the arithmetic / control circuit 14B.

[0014] In the above configuration, the calculation / control circuit 14B includes a 3D pixel pattern calculation circuit 14B1 that calculates and outputs 3D pixel pattern data for the display panel 14C based on the 3D video data, a voltage output circuit 14B2 that receives the 3D pixel pattern data and outputs a voltage signal for causing each pixel of the display panel 14C to perform an operation corresponding to the 3D pixel pattern data, and a backlight lighting circuit 14B3 that controls the waveguide and light source that constitute the backlight 14D based on the voltage signal output of the voltage output circuit 14B2 and the 3D pixel pattern. In the above configuration, three-dimensional pixel pattern calculation circuit 14B1 calculates three-dimensional pixel pattern data suitable for a display device, such as display panel 14C, and adapted to the configuration (number of pixels, number of stacked pixels) of the display device.

[0015] The display panel 14C includes a wiring pattern portion 14C1 that transmits a voltage signal, and a three-dimensional pixel unit 14C2 that is connected to the wiring pattern portion 14C1 and is made of an optical material that functions as an interference fringe.

[0016] The backlight 14D includes a monochromatic or polychromatic light source 14D1 that emits illumination light to irradiate the display panel 14C, and a waveguide 14D2 that guides the illumination light emitted by the light source 14D1 to the display panel 14C.

[0017] Here, the configuration of the three-dimensional pixel unit 14C2 that constitutes the display panel 14C will be described.

[0018] FIG. 2 is a schematic perspective view of an example of the structure of a three-dimensional pixel unit. The three-dimensional pixel unit 14C2 includes a display pixel portion 21, Z-direction pixel selection lines 26, X-direction pixel selection lines 28, wiring 27, and Y-direction pixel selection lines 29. It has 29. In the following description, the extension direction of the Y direction pixel selection line 29 is defined as the Y direction, the stacking direction of the pixels is defined as the Z direction, and the direction perpendicular to the Y direction and the Z direction is defined as the X direction.

[0019] The display pixel section 21 has a plurality of pixels arranged three-dimensionally, and the optical material constituting each pixel is made of a material whose refractive index or transmittance can be changed depending on the voltage application state. In this case, as described below, in each pixel, a driving voltage is applied between a central electrode extending in the Z direction, which is in a selected state by a transistor acting as a switching element, and a horizontal plate electrode, which is in a selected state by a transistor acting as a switching element, thereby changing optical characteristics such as refractive index and transmittance.

[0020] In this case, the transistors serving as switching elements are disposed on the upper surface (surface in the +Z direction) or the lower surface (surface in the -Z direction) of the display pixel section 21 of the three-dimensional pixel unit 14C2.

[0021] In this case, a channel is located between an X-direction pixel selection line 28 connected to the gate of each transistor and a Y-direction pixel selection line 29 connected to the drain of each transistor.

[0022] Furthermore, a thin gate insulating film is disposed between the channel and the X-direction pixel selection line 28, providing insulation.

[0023] As a result, by applying a drive voltage to an X-direction pixel selection line 28 corresponding to one of the gates and a Y-direction pixel selection line 29 corresponding to one of the drains, a channel is opened at a position where the X-direction pixel selection line 28 and the Y-direction pixel selection line 29 are perpendicular to each other, and the drain voltage is transmitted only to the corresponding pixel string described below. At the same time, by selecting one of the Z-direction pixel selection lines 26 and applying a voltage to it, the optical properties such as the refractive index and transmittance of only the corresponding pixel are changed.

[0024] Specifically, the optical material layer 132 is made of an electrochromic material such as liquid crystal or an electro-optical polymer. Electrochromic materials are substances whose optical properties, such as refractive index, light transmittance, and plane of polarization, change when a voltage or current is applied. Moreover, electrochromic materials include inorganic electrochromic materials and organic electrochromic materials.

[0025] Examples of inorganic electrochromic materials include tungsten oxide (WO3), and examples of organic electrochromic materials include methyl viologen and tetrathiafulvalene.

[0026] The Z-direction pixel selection line 26 connects a power source for driving pixels via switching elements to pixels that exist within a predetermined range and have the same position in the Z direction. Furthermore, the Y-direction pixel selection line 29 connects pixels present in a predetermined range and pixels located at the same Y-direction position to a power source for driving pixels via switching elements.

[0027] In the above configuration, a drive circuit (not shown) is connected to the Z-direction pixel selection line 26 made of a transparent optical material, and the voltage applied thereto is controlled by this drive circuit. The Z-direction pixel selection lines 26 of the display pixel section 21 have a stepped structure. As a result, voltage is applied to the optical material, which is a pixel, by the Z-direction pixel selection line 26 in a selected state, the X-direction pixel selection line 28 in a selected state, and the Y-direction pixel selection line 29 in a selected state, and the optical properties such as the refractive index and transmittance are changed.

[0028] FIG. 3 is an explanatory diagram of a three-dimensional pixel unit. FIG. 3A is an explanatory diagram of an example of the XY direction pixel selection circuit 200. As shown in FIG. The XY direction pixel selection circuit includes a TFT 201 having a gate terminal connected to an X direction pixel selection line 28 for each pixel, a drain terminal connected to a Y direction pixel selection line 29 , and a source terminal connected to a pixel electrode 202 .

[0029] As a result, the pixel string GS located at the intersection of the selected X-direction pixel selection line 28 and the Y-direction pixel selection line 29 is selected.

[0030] FIG. 3B is an explanatory diagram of a selected state of a pixel cell. As shown in FIG. 3B, by selecting any one of the Z direction pixel selection lines 26, a pixel cell GC in a selected pixel string GS is selected and display is performed. Here, display means that, as described above, the color and brightness (c) are shown in the direction of the angle of attack (v) and direction angle (h) from the surface of the three-dimensional pixel unit 14C2 through the action of the selected pixel cell GC, which is the pixel at coordinates (x, y).

[0031] Furthermore, as shown in FIG. 6(B), by turning on the selection switches corresponding to the Z-direction pixel selection line 26, the selected X-direction pixel selection line 28, and the Y-direction pixel selection line 29 to be selected, the selected Z-direction pixel selection line 26S, the selected X-direction pixel selection line 28S, and the selected Y-direction pixel selection line 29S can be selected, making it possible to select one pixel cell GC as a selected pixel cell GCS.

[0032] The above explanation is for the case where the pixel cell GC is switched between transparent and non-transparent, but it is also possible to express intermediate tones by varying the voltage applied to the pixel cell GC. For example, if an electrochromic material with changeable light transmittance is used for the pixel cell GC, it becomes possible to control the transmittance on a pixel cell basis.

[0033] Furthermore, if an electrochromic material capable of changing the refractive index is used for the pixel cell GC, the refractive index can be controlled for each pixel cell. Furthermore, if an electrochromic material capable of changing the polarization plane is used for the pixel cell GC, the polarization plane can be controlled for each pixel cell.

[0034] FIG. 4 is an explanatory diagram of an example of the configuration of a pixel cell. In FIG. 4, a transparent insulating film (not shown) is provided between the Z-direction pixel selection lines 26 that function as opposing conductive films.

[0035] Each pixel cell GC is formed at a position opposing the Y-direction pixel selection line 29 and the Z-direction pixel selection line 26 (within the Z-direction pixel selection line 26), and each pixel cell GC can be controlled individually. That is, the pixel cells GC are arranged along the vertical direction in FIG. 8 at each distance between the opposing Z-direction pixel selection lines 26.

[0036] That is, the three-dimensional pixel unit 14C2 has a cylindrical optical material, a Y-direction pixel selection line 29 that functions as a first line extending into the opening of the optical material, and a laminate in which a Z-direction pixel selection line 26 which is a conductive film and an insulating film (not shown) are alternately stacked, and the optical material and the Y-direction pixel selection line 29 that functions as the first line are integrally arranged to penetrate the laminate along the stacking direction.

[0037] Here, an example of the relationship between the applied voltage and the light transmittance when an electrochromic material whose light transmittance changes is used as the optical material layer 132 will be described.

[0038] FIG. 5 is a diagram illustrating an example of the relationship between the voltage applied to the optical material layer and the light transmittance. In the example of FIG. 5, an optical material layer 132 that is transparent and has high light transmittance when no voltage is applied (applied voltage 0 [V]) is used. Here, the voltage Vth is the voltage at which the light transmittance changes significantly. Moreover, the voltage V1 [V] is set to a voltage that can maintain a sufficiently high light transmittance.

[0039] Furthermore, when a voltage V1×2 [V] that is twice the voltage V1 is applied, the voltage becomes definitely higher than the reaction threshold voltage Vth, and the light transmittance becomes almost constant in a low state.

[0040] Therefore, this is utilized to control the change in the optical characteristics of the pixel cells. FIG. 6 is an explanatory diagram of a method for changing the optical characteristics of a pixel cell. For a certain pixel cell GC, a voltage of +V1 [V] is applied to the Y-direction pixel selection line 29S to be selected, and a voltage of 0 [V] is applied to the Y-direction pixel selection line 29N to be unselected.

[0041] Similarly, a voltage −V1 is applied to the selected Z-direction pixel selection line 26S to be selected, and a voltage of 0 [V] is applied to the non-selected Z-direction pixel selection line 26N. As a result, a voltage V1×2 [V] that is twice the voltage V1 is effectively applied to pixel cell GC1, which is located at the intersection of the Y-direction pixel selection line 29S to be selected and the Z-direction pixel selection line 26S to be selected, causing pixel cell GC1 to become opaque.

[0042] In contrast, a voltage V1 [V] is effectively applied to pixel cell GC2, which is located at the intersection of the selected Y-direction pixel selection line 29S and the non-selected Z-direction pixel selection line 26N, but pixel cell GC2 does not react and remains transparent.

[0043] Similarly, a voltage V1 [V] is effectively applied to pixel cell GC3 located at the intersection of the non-selected Y-direction pixel selection line 29N and the selected Z-direction pixel selection line 26S, but pixel cell GC3 does not react and remains transparent.

[0044] FIG. 7 is a diagram illustrating an example of a control state of a three-dimensional pixel unit. As shown in FIG. 7, the three-dimensional pixel unit 14C2 is in a state in which a selected pixel cell GCS that is opaque and a transparent non-selected pixel cell GCN are arranged three-dimensionally. As a result, when the illumination light L emitted from the backlight 14D passes through the three-dimensional pixel unit 14C2, the three-dimensional pixel unit 14C2 functions as a transmission-type hologram display device, making it possible to display a light-reproduction-type three-dimensional image corresponding to multiple viewpoints.

[0045] In this case, the three-dimensional pixel unit 14C2 functions as an interference fringe volume type, and the interference fringes can be realized as a refractive index distribution or a transmittance distribution inside the material.

[0046] Furthermore, because the optical materials or light path control elements and their control wiring are arranged three-dimensionally, dynamically changeable interference fringes can be formed. Therefore, it is also possible to perform holographic display of moving images.

[0047] As described above, in the three-dimensional image display device of this embodiment, the optical materials or light path control elements and their control wiring are arranged in a manner similar to the charge storage materials and wiring in a three-dimensional memory, thereby making it possible to manufacture the device by layered film formation and microfabrication. Therefore, it becomes possible to manufacture a popular autostereoscopic display that can be mass-produced.

[0048] In the above explanation, light source 14D1 has not been described in detail, but it is also possible to configure the device to display color images by providing light sources of multiple colors and reproducing stereoscopic images corresponding to the light sources of each color in a time-division manner. In the above description, a case has been described in which the three-dimensional pixel unit 14C2 is provided, but even with only one layer, it is possible to perform display similar to that of a conventional transmission type hologram device.

[0049] FIG. 8 is a conceptual explanatory diagram of another configuration example of a pixel cell. In FIG. 8, it is assumed that a transparent insulating film (not shown) is provided between the opposing Z-direction pixel selection lines 26 and between the Y-direction pixel selection line 29A and the opposing Z-direction pixel selection line 26. Each pixel cell GC is formed at a position opposing the Y-direction pixel selection line 29A and the Z-direction pixel selection line 26 (within the Z-direction pixel selection line 26), and each pixel cell GC can be controlled individually.

[0050] That is, the pixel cells GC are arranged along the vertical direction in FIG. 12 at each distance between the opposing Z-direction pixel selection lines 26. That is, the three-dimensional pixel unit 14C2 has a plate-shaped optical material, a Y-direction pixel selection line 29A that functions as a first line extending along the extension direction of the optical material so as to be in electrical contact with the optical material, and a laminate in which the Z-direction pixel selection line 26 which is a conductive film and an insulating film (not shown) are alternately stacked, and the optical material and the Y-direction pixel selection line 29A that functions as the first line are arranged to penetrate the laminate along the stacking direction, with the Y-direction pixel selection line 29A that functions as the first line being insulated from the Z-direction pixel selection line 26 which is a conductive film. With this configuration as well, it is possible to display a stereoscopic image in the same manner as with the configuration shown in FIG.

[0051] The arithmetic / control circuit 14B of this embodiment has a hardware configuration using a normal computer, and includes a control device such as a CPU, a high-speed arithmetic device capable of image processing such as a GPU, and a storage device such as a ROM (Read Only Memory), RAM, etc. Also, an external storage device such as an SSD or HDD may be included as necessary.

[0052] The program executed by the arithmetic / control circuit 14B of this embodiment is provided in an installable or executable format file recorded on a computer-readable recording medium such as a semiconductor storage device such as an SSD or a USB memory, or a DVD (Digital Versatile Disk).

[0053] The program executed by the arithmetic / control circuit 14B of the present embodiment may be stored in a computer connected to a network such as the Internet and provided by being downloaded via the network. The program executed by the arithmetic / control circuit 14B of the present embodiment may be provided or distributed via a network such as the Internet.

[0054] The program for the arithmetic / control circuit 14B of this embodiment may be provided by being pre-installed in a ROM or the like.

[0055] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0056] 10. Stereoscopic Image Display System 11 3D image information generating device 11A Imaging Device 12 Data conversion device 12A Transfer information generating device 12B Storage 13 Information transfer device 13A Input Device 13B Broadcasting Equipment 14 3D image display device 14A Receiver 14B Calculation / control circuit 14C Display Panel 14D Backlight 21 Display pixel section 26 Z-direction pixel selection lines 26N Non-selected Z-direction pixel selection line 26S Select Z-direction pixel selection line 28 X-direction pixel selection lines 29, 29A Y-direction pixel selection line 29S Select Y-direction pixel selection line GC pixel cell GCN Unselected pixel cell GCS Selected Pixel Cell GS pixel string L illumination light SGD Drain Side Select Transistor SGS Source side select transistor Vth Reaction threshold voltage

Claims

1. A light reproduction type stereoscopic image display device capable of naked eye stereoscopic viewing, comprising: a three-dimensional pixel unit in which a plurality of pixel cells formed of an optical material whose optical characteristics are electrically changeable are three-dimensionally arranged and electrically connected to the plurality of pixel cells by a transparent wiring pattern; A backlight that emits illumination light to the three-dimensional pixel unit; an arithmetic / control circuit that individually controls the pixel cells via the wiring pattern based on input three-dimensional image data, and arranges pixel cells whose optical characteristics are changed three-dimensionally and pixel cells whose optical characteristics are not changed, thereby making the three-dimensional pixel unit function as a transmission hologram capable of forming an image from multiple viewpoints; A stereoscopic image display device comprising:

2. The three-dimensional pixel unit is configured by stacking two-dimensionally arranged pixel cells in a plurality of layers with insulating films interposed therebetween.

2. The stereoscopic image display device according to claim 1.

3. the three-dimensional pixel unit includes a cylindrical optical material, a first line extending into an opening of the optical material, and a laminate in which a conductive film and an insulating film are alternately laminated; The optical material and the first line are integrally disposed so as to penetrate the laminate along the lamination direction.

3. The stereoscopic image display device according to claim 1.

4. the three-dimensional pixel unit includes an optical material extending in a predetermined direction, a first line extending along the extension direction of the optical material so as to be in electrical contact with the optical material, and a laminate in which a conductive film and an insulating film are alternately laminated; the optical material and the first line are integrally disposed to penetrate the laminate along a lamination direction, with the first line being insulated from the conductive film; 3. The stereoscopic image display device according to claim 1.

5. As the optical material, an electrochromic material such as a liquid crystal or an electro-optical polymer is used. The stereoscopic image display device according to claim 1 .

6. the arithmetic / control circuit includes a three-dimensional pixel pattern calculation circuit that calculates and outputs three-dimensional pixel pattern data in the three-dimensional pixel unit based on the three-dimensional image data; a voltage output circuit to which the three-dimensional pixel pattern data is input and which outputs a voltage signal for causing each pixel of the three-dimensional pixel unit to perform an operation corresponding to the three-dimensional pixel pattern data; The stereoscopic image display device according to claim 1 , further comprising:

7. The backlight comprises light sources of multiple colors; the arithmetic / control circuit displays a color image by reproducing stereoscopic images corresponding to the respective light sources in a time-division manner; The stereoscopic image display device according to claim 1 .

Images