Stereo display control device and its program

Abstract

To provide a 3D display control device capable of displaying a hardly blurred stereoscopic image with no restriction on observation distance .SOLUTION: A 3D display control device 4 includes: element image group generation means 40 for generating an element image group E according to a viewpoint position, and causing a display element 20 to display the generated element image group E; and element lens drive means 41 for calculating a focal length of a variable focus element lens 22 so as to converge a light beam from the variable focus element lens 22 at the viewpoint position, and driving the variable focus element lens 22 by using the calculated focal length.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a stereoscopic display control device and a program therefor.

Background Art

[0002] Among ray-reproducing stereoscopic video display devices, the integral stereoscopic display device 9 in FIG. 4 and the multi-viewpoint stereoscopic video display device 9B in FIG. 5 have similar optical configurations. Both the integral stereoscopic display device 9 and the multi-viewpoint stereoscopic video display device 9B include a display element 90 that displays an element image group E composed of element images e, and a lens array 91 in which element lenses 92 are two-dimensionally arranged.

[0003] In addition, FIGS. 4 and 5 illustrate the right side S R of the viewing field formed by the pair of the element image e and the element lens 92 L and the left side S of the viewing field. FIGS. 4 and 5 also illustrate a three-dimensional coordinate system in which the horizontal direction is X, the vertical direction is Y, and the depth direction is Z.

[0004] The integral stereoscopic display device 9 in FIG. 4 forms rays without assuming a specific viewing distance z (Non-Patent Document 1). That is, in the integral stereoscopic display device 9, an observer A can observe a stereoscopic image at an arbitrary viewing distance z. This viewing distance z represents the distance between the lens array 91 and the viewpoint position of the observer A in the depth direction.

[0005] On the other hand, in the multi-viewpoint stereoscopic video display device 9B in FIG. 5, the viewing distance z is fixed, and it is different from the integral stereoscopic display device 9 in that rays are condensed at the viewing distance z. Further, the rays formed by the individual element lenses 92 are parallel rays in the integral stereoscopic display device 9, whereas they are convergent rays in the multi-viewpoint stereoscopic video display device 9B. For this reason, in the multi-viewpoint stereoscopic video display device 9B, the rays are thinner than those in the integral stereoscopic display device 9 at the viewing distance z, so that the stereoscopic video is less likely to be blurred.

Prior Art Documents

Non-Patent Documents

[0006] [Non - Patent Document 1] Development of a viewpoint - following integral 3D video display system, Naoto Oka, Hisayuki Sasaki, Masanori Kana, Masahiro Kawakami, Ken Shiraimura [Summary of the Invention] [Problems to be Solved by the Invention]

[0007] As described above, the integral stereoscopic display device 9 can observe a stereoscopic image at an arbitrary observation distance z. On the other hand, as the depth position of the stereoscopic image moves away from the lens array 91, the light - ray density decreases and the stereoscopic image becomes blurred. On the other hand, in the multi - viewpoint stereoscopic video display device 9B, although the stereoscopic image is less likely to be blurred even when the depth position of the stereoscopic image moves away from the lens array 91, the observation distance z is fixed. Thus, in the prior art, it has been difficult to display a stereoscopic image that is not easily blurred without being restricted by the observation distance.

[0008] Therefore, an object of the present invention is to provide a stereoscopic display control device and its program, and a stereoscopic display device and its program that can display a stereoscopic image that is not easily blurred without being restricted by the observation distance. [Means for Solving the Problems]

[0009] In order to solve the above problems, the stereoscopic display control device according to the present invention is a stereoscopic display control device that controls a stereoscopic display device including a display element that displays an element image group composed of element images, and a variable - focus lens array in which variable - focus element lenses with variable focal lengths are arranged corresponding to the element images. The stereoscopic display control device is configured to include element image group generation means and element lens driving means.

[0010] According to such a configuration, the element image group generation means receives the viewpoint position of the observer, generates an element image group corresponding to the input viewpoint position, and causes the generated element image group to be displayed on the display element. The element lens driving means calculates the focal length of the variable focal element lens based on the observation distance from the viewpoint position to the variable focal lens array and the distance from the variable focal lens array to the display element, so that the light rays from the variable focal element lens converge at the viewpoint position, and drives the variable focal element lens with the calculated focal length.

[0011] By such control, in the stereoscopic display device, the variable focal element lens has a focal length corresponding to the observation distance, and the display element displays an element image group corresponding to the viewpoint position. Therefore, the observation distance is not restricted, and the stereoscopic image is less likely to be blurred.

[0012] The present invention can also be realized by a program for causing a computer to function as the above-described stereoscopic display control device.

Effects of the Invention

[0013] According to the present invention, a stereoscopic image that is not easily blurred can be displayed without restricting the observation distance.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, each of the embodiments described below is for embodying the technical idea of the present invention, and the present invention is not limited to the following unless specifically described. Also, the same means may be denoted by the same reference numerals, and the description may be omitted.

[0016] (Embodiment) [Overview of the stereoscopic display system] Referring to FIG. 1, the overview of the stereoscopic display system 1 will be described. The stereoscopic display system 1 displays a stereoscopic video (element image group E) according to the viewpoint position of the observer A, and as shown in FIG. 1, includes a stereoscopic display device 2, a viewpoint position detection device 3, and a stereoscopic display control device 4. The stereoscopic display device 2 is a display that displays a stereoscopic video, and includes a display element 20 and a variable focus lens array 21.

[0017] The display element 20 displays an element image group E composed of element images e. In the present embodiment, the display element 20 receives a video signal of the element image group E from an element image group generation means 40 described later and displays the element image group E. For example, as the display element 20, general flat panel displays such as a liquid crystal display, an organic EL (Electro Luminescence) display, and a plasma display can be mentioned.

[0018] The variable focus lens array 21 is an array in which variable focus element lenses 22 with variable focal lengths are arranged so as to correspond to the element images e. In the present embodiment, the variable focus lens array 21 changes the focal length according to a drive signal input from an element lens drive means 41 described later. For example, as the variable focus element lens 22, general ones such as a droplet dielectric lens and a liquid variable focus lens can be mentioned (for example, Japanese Patent Application Laid-Open No. 2010-107908). This droplet dielectric lens is transparent and has fluidity, and changes the focal length by changing the shape of a droplet-shaped dielectric having a high refractive index with respect to air by the voltage applied to the electrode.

[0019] In this embodiment, the display element 20 is configured to display an element image group E in which the element images e are arranged in two-dimensional directions (horizontal and vertical directions), similar to the integral method. Accordingly, in the variable focus lens array 21, the variable focus element lenses 22 are arranged in two-dimensional directions.

[0020] The viewpoint position detection device 3 detects the viewpoint position of the observer A and outputs the detected viewpoint position to the stereoscopic display control device 4. For example, the viewpoint position detection device 3 is a viewpoint position detection camera that performs viewpoint position detection processing on an image captured by a normal visible light camera to detect the viewpoint position in three-dimensional directions (horizontal direction, vertical direction, and depth direction). Also, the viewpoint position detection device 3 may synchronize an infrared camera and an infrared illumination device and detect the viewpoint position by the TOF (Time of Flight) method. Further, the viewpoint position detection device 3 may attach an optical or magnetic marker to the head of the observer and detect the position of the marker as the viewpoint position. Furthermore, the viewpoint position detection device 3 may detect the viewpoint position by combining the above-described various methods.

[0021] In FIG. 1, for ease of viewing the drawing, the viewpoint position detection device 3 is arranged behind the stereoscopic display device 2. However, the arrangement position of the viewpoint position detection device 3 is not particularly limited as long as it can detect the viewpoint position of the observer A.

[0022] [Configuration of Stereoscopic Display Control Device] Hereinafter, the configuration of the stereoscopic display control device 4 will be described. The stereoscopic display control device 4 controls the stereoscopic display device 2 and includes, as shown in FIG. 1, an element image group generation means 40 and an element lens driving means 41.

[0023] The element image group generation means 40 receives the viewpoint position of the observer A from the viewpoint position detection device 3, generates an element image group corresponding to the input viewpoint position, and causes the generated element image group E to be displayed on the display element 20. In the present embodiment, the element image group generation means 40 performs ray tracing on a three-dimensional model of a stereoscopic image to generate an element image group for each frame (for example, see Reference 1). Then, the element image group generation means 40 outputs a video signal of the element image group E to the display element 20.

[0024] Reference 1: Katayama, Conversion method from a three-dimensional model to an integral stereoscopic image, NHK Technical Research and Development / No. 128, July 2011

[0025] The element lens driving means 41 calculates the focal length f of the variable focus element lens 22 based on the observation distance z from the viewpoint position to the variable focus lens array 21 and the distance g from the variable focus lens array 21 to the display element 20 so that the light rays from each variable focus element lens 22 converge at the viewpoint position. This observation distance z represents the distance between the variable focus lens array 21 and the viewpoint position of the observer A in the depth direction. At this time, the element lens driving means 41 calculates the focal length f so as to be synchronized with the video signal of the element image group E, and outputs a driving signal for driving the variable focus element lens 22 at the focal length f to the variable focus element lens 22.

[0026] <Shift of the element image group, control of the focal length> Referring to FIG. 2, the shift of the element image group and the control of the focal length will be specifically described. In the conventional integral stereoscopic display device 9 (FIG. 4), element images e corresponding to the element lenses 92 are arranged directly behind the element lenses 92. That is, in the conventional integral stereoscopic display device 9, the central positions of each element lens 92 and each element image e coincide in the horizontal and vertical directions.

[0027] On the other hand, the stereoscopic display device 2 can expand the viewing field by moving (shifting) the center positions of the respective element images e in the horizontal and vertical directions according to the viewpoint position of the observer A. This corresponds to expanding the overall size of the element image group E according to the viewing distance z with the element image e displayed at the center of the stereoscopic display device 2 as the center (when the viewing distance z is infinite, it corresponds to the integral method).

[0028] When the viewpoint position moves in the horizontal or vertical direction, the element image group generation means 40 shifts the element image group E to the side opposite to the moving direction of the viewpoint position. Further, when the viewpoint position approaches the stereoscopic display device 2, the element image group generation means 40 enlarges the element image group E, and when the viewpoint position moves away from the stereoscopic display device 2, the element image group generation means 40 reduces the element image group E. At this time, the element image group generation means 40 makes the interval between the element images e constituting the element image group larger than the interval between the variable focus element lenses 22 constituting the variable focus lens array 21.

[0029] For example, the element image group generation means 40 may shift, enlarge, or reduce the element image group E according to the moving direction and moving amount of the viewpoint position with respect to a preset reference viewpoint position. Note that the reference viewpoint position is the viewpoint position of the reference observer A. For example, the reference viewpoint position is in front of the stereoscopic display device 2 (on the optical axis of the 0th variable focus element lens 220) and at a position with a predetermined viewing distance z.

[0030] For simplicity of explanation, consider the X-Z plane. As shown in FIG. 2, the variable focus element lens 22 whose optical axis passes through the reference viewpoint position is taken as the 0th variable focus element lens 220. The optical axis of the variable focus element lens 22 is a straight line perpendicular to the lens surface of the variable focus lens array 21. Then, the 1st variable focus element lens 221,..., the nth variable focus element lens 22 n are arranged in order from the variable focus element lens 220 to the left and right (where n is an integer of 2 or more). In FIG. 2, for ease of viewing the drawing, the configuration of the display element 20 is omitted and only the reference numerals are shown.

[0031] Let the lens interval of the variable focus element lens 22 be p. For the center position x n of the n-th variable focus element lens 22 n , let the shift amount of the center position of the n-th element image e n be Δx n . In this case, the element image group generation means 40 shifts the element image e n corresponding to the n-th variable focus element lens 22 n by the shift amount Δx n represented by the following formula (1) in the horizontal direction. Further, the element image group generation means 40 enlarges the size of the element image e n corresponding to the n-th variable focus element lens 22 n by Δx1 (excluding the 0-th variable focus element lens 220). That is, the center position of the n-th element image e n becomes np + Δx n , and the interval between adjacent element images e becomes p + Δx1. By shifting the element image group E in this way, the viewing field becomes the widest at the position of the observer A.

[0032]

Equation

[0033] In the example of FIG. 2, since the element image e0 is located directly behind the variable focus element lens 220, the shift amount Δx0 = 0, and the element image e0 does not shift. Also, the element image e1 shifts horizontally by the shift amount Δx1 and its size is enlarged by the shift amount Δx1. Further, the element image e n shifts horizontally by the shift amount Δx n and its size is enlarged by the shift amount Δx1. Note that, similar to the horizontal direction (X-axis direction), the element image group E may be shifted in the vertical direction (Y-axis direction).

[0034] The element lens driving means 41 calculates the focal length f using the following formula (2) such that the light rays from the variable focal length element lens 22 are thinnest at the viewpoint position. By controlling the focal length f in this way, at the viewpoint position, the light rays from the individual variable focal length element lenses 22 are focused and the light rays become thinnest, so that the stereoscopic image is less likely to be blurred.

[0035]

Equation

[0036] As described above, in the stereoscopic display control device 4, when generating the element image group E corresponding to the viewpoint position of the observer A, the viewing area determined by the combination of each element image e and the variable focal length element lens 22 is not in a parallel state as shown in FIG. 4, but corresponds to the observation distance z as shown in FIG. 5. At the same time, in the stereoscopic display control device 4, by shifting the entire element image group E in the horizontal and vertical directions, the viewing area of the entire stereoscopic video is optimized according to the viewpoint position of the observer A. As a result, the stereoscopic display control device 4 can observe a stereoscopic image in a wider range compared to the prior art.

[0037] [Operation of the stereoscopic display control device] Referring to FIG. 3, the operation of the stereoscopic display control device 4 will be described. As shown in FIG. 3, in step S1, the viewpoint position is input from the viewpoint position detection device 3 to the stereoscopic display control device 4.

[0038] In step S2, the element image group generation means 40 generates an element image group corresponding to the viewpoint position input in step S1. At this time, when the viewpoint position moves in the horizontal or vertical direction, the element image group E is shifted to the side opposite to the moving direction of the viewpoint position. Further, when the viewpoint position approaches the stereoscopic display device 2, the element image group E is enlarged, and when the viewpoint position moves away from the stereoscopic display device 2, the element image group E is reduced.

[0039] In step S3, the element image group generation means 40 causes the display element 20 to display the element image group E generated in step S2. That is, the element image group generation means 40 outputs the video signal of the element image group E to the display element 20.

[0040] In step S4, the element lens driving means 41 calculates the focal length f of the variable focal length element lens 22 based on the observation distance z and the distance g so that the light rays from each variable focal length element lens 22 converge at the viewpoint position. Specifically, the element lens driving means 41 calculates the focal length f using the above-described formula (2) so that the light rays from the variable focal length element lens 22 are the thinnest at the viewpoint position.

[0041] In step S5, the element lens driving means 41 drives the variable focal length element lens 22 so as to obtain the focal length f calculated in step S4. That is, the element lens driving means 41 outputs a driving signal with the focal length f to the variable focal length element lens 22. Note that in the stereoscopic display control device 4, these processes may be executed in parallel so that the processes of steps S2 and S3 and the processes of steps S4 and S5 are synchronized.

[0042] [Operation and Effect] As described above, the stereoscopic display control device 4 according to the embodiment controls the stereoscopic display device 2 so that the variable focal length element lens 22 has a focal length corresponding to the observation distance z and the display element 20 displays an element image group corresponding to the viewpoint position. Thereby, in the stereoscopic display device 2, the observation distance z is not restricted, and the stereoscopic image is less likely to be blurred.

[0043] Although the embodiments and examples have been described in detail above, the present invention is not limited to the above-described embodiments and examples, and also includes design changes and the like within a range not departing from the gist of the present invention.

[0044] In the above-described embodiments, a stereoscopic display device having parallax in two-dimensional directions, such as an integral type, is assumed, but the present invention is not limited thereto. For example, the stereoscopic display control device can also be applied to a stereoscopic display device having parallax only in one-dimensional direction, such as a lenticular method. In this case, the stereoscopic display device includes a variable focus lens array in which pillow-shaped lenticular lenses (variable focus element lenses) are arranged in the horizontal direction, and a display element including an element image group in which element images corresponding to the lenticular lenses are arranged in a stripe shape.

[0045] In the above-described embodiments, the stereoscopic display control device has been described as being independent hardware, but the present invention is not limited thereto. For example, the present invention can also be realized by a program for causing hardware resources such as a CPU, a memory, and a hard disk included in a computer to function as the above-described stereoscopic display control device. This program may be distributed via a communication line, or may be written on a recording medium such as a CD-ROM or a flash memory and distributed.

Explanation of Reference Numerals

[0046] 1 Stereoscopic display system 2 Stereoscopic display device 3 Viewpoint position detection device 4 Stereoscopic display control device 9 Integral stereoscopic display device 9B Multi-viewpoint stereoscopic video display device 20 Display element 21 Variable focus lens array 22 Variable focus element lens 40 Element image group generation means 41 Element lens drive means 90 Display element 91 Lens array 92 Element lens

Claims

1. A stereoscopic display control device for controlling a stereoscopic display device including a display element that displays an element image group composed of element images, and a variable focus lens array in which variable focus element lenses with variable focal lengths are arranged so as to correspond to the element images, element image group generation means for inputting a viewpoint position of an observer, generating the element image group corresponding to the input viewpoint position, and causing the generated element image group to be displayed on the display element; element lens driving means for calculating a focal length of the variable focus element lens so that a light beam from the variable focus element lens converges at the viewpoint position based on an observation distance from the viewpoint position to the variable focus lens array and a distance from the variable focus lens array to the display element, and driving the variable focus element lens with the calculated focal length; The stereoscopic display control device characterized by comprising the above.

2. The stereoscopic display control device according to claim 1, wherein when the viewpoint position moves in the horizontal direction or the vertical direction, the element image group generation means shifts the element image group to the side opposite to the moving direction of the viewpoint position, and when the viewpoint position approaches the stereoscopic display device, the element image group generation means enlarges the element image group, and when the viewpoint position moves away from the stereoscopic display device, the element image group generation means reduces the element image group.

3. The element lens driving means uses the following formula (2) in which the observation distance is z and the distance from the variable focus lens array to the display element is represented by g, 【Number 1】 The stereoscopic display control device according to claim 1 or claim 2, wherein the focal length f is calculated so that the light beam from the variable focus element lens is the thinnest at the viewpoint position.

4. A program for causing a computer to function as the stereoscopic display control device according to any one of claims 1 to 3.

Images