JPH03226095A - Stereoscopic picture display device - Google Patents

Abstract

PURPOSE:To realize stereoscopic picture display without eyeglass with less limit of a visual position attended with a natural motion parallax by arranging plural two- dimension optical modulation means side by side in the direction of depth able to control light shield or light transmission for each picture element and using a controller provided separately so as to control the two-dimension optical modulation means. CONSTITUTION:Two-dimension modulation means Qm (m=1-n) able to control the light transmission state from a rear face for each picture element are prepared and n-set of the means are arranged in the depth direction. Let a two-dimension optical modulation means placed most this side with respect to the observer observing the display device be the means Q1. Then a stereoscopic picture is displayed by allowing a two-dimension optical modulation use controller DC to control the two-dimension optical modulation means Q1-Qn as follows. That is, one of the two-dimension optical modulation means Q1-Qn is selected as a main modulation means, on which a picture is displayed, light is transmitted in the two-dimension optical modulation means remote from the observer and the two-dimension optical modulation means close to the observer shields the light based on a background signal generated separately and all the two-dimension optical modulation means are controlled to be in use as the main modulation means in time division.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a stereoscopic image display device, and particularly to a stereoscopic image display device that does not require unnecessary glasses such as polarized glasses or liquid crystal shutter glasses.

(Summary of the Invention) This invention relates to a stereoscopic image display device without glasses,
Multiple 2 panels that can control light shielding or transmission for each pixel
A dimensional light modulation means is prepared, a plurality of these two-dimensional light modulation means are arranged in parallel in the depth direction, and a separately provided control device controls these two-dimensional light modulation means, and a three-dimensional image is created by controlling light transmission and shielding. is displayed.

In this way, it is possible to provide a stereoscopic image display device without glasses that has natural motion parallax and fewer restrictions on the viewpoint position.

(Prior Art) Conventional stereoscopic image display devices without glasses include the following.

First, a semi-cylindrical lenticular lens or a vertical grid is pasted onto a display such as an ordinary CRT.
An optical positional relationship is created in which only a part of the display can be seen at a certain eye position. At this time, since the spatial positions of the left and right eyes are different, each eye can see different parts of the display. At this time, if an image for the left eye is displayed in the part of the display that is viewed by the left eye, and an image for the right eye is displayed in the part of the display that is viewed by the right eye, the viewer can see stereoscopically without glasses. This can be said to be multiplexing images corresponding to various eye positions on the display.

The above will be explained in more detail with reference to the attached FIGS. 6 and 7. Figure 6 shows a vertical grid VM on the display surface DPS.
This is a diagram showing the positional relationship when S is attached, as seen from a position directly above the display. a, b on the display surface
Assume that four images P, , c, and d are displayed multiplexed as shown in FIG. If this display DPS is covered with an appropriate vertical grid VMS as shown in FIG. 6, the areas Pl, P2. P.L.
, P3. Each area of PR1P, P5 is an area where only a can be seen, an area where a and b can be seen, an area where only b can be seen,
There will be an area where b and C can be seen, an area where only C can be seen, an area where C and d can be seen, and an area where only d can be seen, and depending on the viewing position, only one of images a, b, c, and d will be visible. For example, if the left eye is located at area P in FIG.
, l, the left eye sees the image, but the right eye sees only the image C. Therefore, if the images for the left eye and the right eye are displayed in advance in the images (a) and (c), stereoscopic vision can be achieved without glasses. The above is the basic idea of conventional stereoscopic image display without glasses.

(Problem to be solved by the invention) The conventional technology has the following problems.

First, since images corresponding to various eye positions are multiplexed on the display, the resolution decreases at the rate of multiplexing. For example, if two images for the left eye and the right eye are multiplexed on a display with a horizontal resolution of 600 lines, the horizontal resolution of the image for one eye will be 300 lines. Also,
In the example of FIG. 6, four images are multiplexed, so there are 150 images. As described above, the more multiple images are multiplexed, the lower the resolution of the visible image becomes.

Second, observation positions are limited. If the left eye exists at the position of point Qt indicated by the broken line in Figure 6, and the right eye exists at the position of QR, two images a and b will appear in the left eye, and two images c and d will appear in the right eye, which is extremely unnatural. It will look different.

The above are problems with the conventional method in which a vertical grid is pasted on the display, but the conventional method in which a lenticular lens is pasted also has exactly the same problems.

The reason for this problem is that images corresponding to various eye positions are multiplexed on the display surface.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems and provide a stereoscopic image display device without glasses that has natural interlocking parallax and fewer restrictions on the viewpoint position.

(Means for Solving the Problems) In order to achieve this object, the three-dimensional image display device according to the present invention includes a front thread device that includes a plurality of two-dimensional light modulation means that can control the shielding or transmission of light for each pixel. Along with providing
In order to display a three-dimensional image, the present invention is characterized by comprising a two-dimensional light modulation means control device that controls a plurality of two-dimensional light modulation means arranged in parallel in the depth direction.

Furthermore, in a preferred embodiment of the present invention, the two-dimensional light modulation means control device controls the plurality of two-dimensional light modulation means, one of the plurality of two-dimensional light modulation means as a main modulation means. The main modulation means displays the image, the two-dimensional light modulation means located further from the main modulation means transmits the light, and the two-dimensional light modulation means located closer to the main modulation means transmits the light. The means is characterized in that the light is blocked based on a separately generated background signal, and all the two-dimensional light modulation means are controlled in a time-division manner so as to function as the main modulation means.

Furthermore, on December 8, 1989, the applicant became the applicant prior to filing this application.
The "stereoscopic image display device" submitted by the Japan Patent Office on the date was proposed with the same purpose as this application, and it is a two-dimensional image display device consisting of a light modulation means that modulates light from the rear surface and a light emitting means that emits light by itself. Although the display means are arranged side by side in the depth direction, the present invention constructs a two-dimensional image display means without the need for a light emitting means by appropriately controlling the light modulation means.

(Function) Now, according to the stereoscopic image display device according to the present invention as described above, a plurality of images corresponding to different parallaxes are multiplexed in the depth direction, unlike the conventional planar arrangement, so that the resolution can be improved. It is possible to display a stereoscopic image with natural motion parallax and fewer restrictions on the viewpoint position without any decrease in the image quality.

(Example) The present invention will be described in detail below by way of examples with reference to the accompanying drawings, but before going into the description of this example, the principles of the stereoscopic image display device according to the present invention will be explained.

A description will be given with reference to FIG. 1 showing the basic configuration of the display device of the present invention. First, two-dimensional light modulation means Q m (m
= 1.2. --------, Prepare n).

The transmission state here refers to the transmittance that includes the wavelength characteristics of light, and the control of the transmission state means changing the intensity and color of the transmitted light for each pixel.

n pieces of this two-dimensional light modulation means are arranged in the depth direction as shown in FIG. The two-dimensional light modulation means located closest to the observer viewing this display device, that is, the most front side in FIG. and number them up to Qn. Therefore, a three-dimensional image is displayed by controlling each of the two-dimensional light modulating means Q1 to Q as follows.

That is, first, each two-dimensional light modulation means Q, -Q.

Based on the following criteria, the main modulation means, sub-modulation means, non-modulation means, and last regenerative modulation means, which is a type of main modulation means, are
Classify into types. Value m that changes in time division (m = L
2. ---, n), two-dimensional light modulation means Q
, % become the main modulation means or the last regenerative modulation means in sequence in a time-division manner. Here, when m<H, the two-dimensional light modulating means Q6 is the main modulating means, and when m=n, the two-dimensional light modulating means Q1 is the last regenerative modulating means. Regarding two-dimensional light modulation means other than Q1, two-dimensional light modulation means Qk where k<m
is the sub-modulation means, and the remaining two-dimensional light modulation means Q with k>m
.

is a non-modulated means. Last regeneration modulation means Q, (m=n)
is the image signal S. Display as is. In other words, bright parts of the image transmit more light, and dark parts transmit less light. When a certain pixel in the image signal S7 is an object, the main modulation means Q, (m<n) displays that pixel in the same way as the last regeneration modulation means, and in other cases, it does not transmit but blocks it. It works like this. The sub-modulation means Qm (k<m) operates so that when a certain pixel in the image signal Sk is a subject, the pixel does not transmit light but blocks it, and in other cases, it transmits the light. Further, the non-modulating means Qk (kpm) transmits light unconditionally.

As described above, the operation of each two-dimensional light modulating means Q for a given m (the number of the two-dimensional light modulating means serving as the main modulating means or the last regenerative modulating means) is determined. Therefore, if the value of m is changed from 1 to n in a time division manner for each field of the image, a three-dimensional image will be displayed.

In FIG. 1, the control device CD for the two-dimensional light modulation means includes all the above-mentioned controls, and its inputs include three two-dimensional image signals (m=L 2+ '
−'−−−−−−'+ n ), and background signal R, (
m=1.2;-.-, n-1) is input and used as a signal to control each two-dimensional light modulation means. Also, the first
The light source shown in the figure is not necessarily an essential requirement for the configuration of the present invention, and if it exists, it may be a light emitting plate with two-dimensionally different illuminance.

In the embodiment illustrated in FIG. 2, as a two-dimensional light modulation means,
Three liquid crystal light modulation plates are arranged in the depth direction. This liquid crystal type light modulation plate is such that the brighter the image input to it, the more light is transmitted, and the darker the image input to it, the more light is blocked, and one that is used in commercially available liquid crystal projectors can be used.

Here, in order to facilitate understanding, the number of liquid crystal light modulation plates is assumed to be three, but the same explanation can be given even when a plurality of liquid crystal light modulation plates other than three are used. In addition, in the following, a red letter R is written on the frontmost liquid crystal light modulation plate C5, a green letter G is written on the rearmost liquid crystal light modulation plate C2, and a green letter G is written on the rearmost liquid crystal light modulation plate C3. An example in which a blue letter B is displayed will be described.

To explain this with reference to FIG. 2, which is an example of the configuration of this embodiment, three liquid crystal light modulation plates are arranged in the normal direction of the liquid crystal light modulation plates, that is, in the depth direction, and the frontmost side is ,
In other words, C+
, Cz, and C3. Further, a light source is placed further behind C3.

On the other hand, three two-dimensional images S1.
S2. S3 and background signals R1 and Rz that clearly indicate in the form of a binary image whether or not a subject exists in each image are prepared (the background signal R3 for the image signal S3 is not necessary) and these are input to the multiplexer MPD. do. Here, it is assumed that the portions of the two-dimensional images Sl and S2 that are not objects have a black signal. Also, the background signal RII (m=1.2) is
The part of the image SII that is the subject becomes a black signal, and the part that is not the subject becomes a white signal. An example of the two-dimensional image signals S, -S and background signals R, -R2 is shown in FIG.
They are shown in a) to (e), respectively.

Therefore, the multiplexer uses the count value m obtained by counting the vertical synchronization signal in three values from 1 to 3 as an external control signal, performs the following multiplexing process, and outputs the image Dk.

For example, D2 is a white signal (m=1) = S z (m
= 2) → R2 (m・3) → White signal (m・1) 3
It is repeated for each field.

Finally, the output image D3 of the multiplexer MPD is input to each liquid crystal light modulation plate Ck.

This will be explained in detail with reference to FIG.

The leftmost fir row in FIG. 4 is the case where m (the number of the liquid crystal light modulation plate serving as the main modulation means or the last regenerative modulation means)=1. In this case, since 01 is the main modulation means, the pixel corresponding to the letter R transmits only red light, and the other pixels block the light. Since C2 and 03 correspond to non-modulating means, they transmit light unconditionally. Therefore, when CI-C3 is placed side by side in the depth direction, the red letter R is visible from the front side.

Next, the central vertical column is for m=2. In this case C
Since 1 corresponds to the sub-modulation means, the pixel corresponding to the letter R blocks light, and the other pixels transmit light.

Further, since C2 corresponds to the main modulation means, the pixel corresponding to the letter G transmits only green light, and the other pixels block the light. Since C3 corresponds to a non-modulating means, it transmits light. Therefore, when C8 to C3 are arranged side by side in the depth direction, it appears from the front side that the black letter R is overlaid in front of the green letter G.

The rightmost vertical column is for m=3.

In this case, 01 corresponds to the sub-transformation means, so the pixel corresponding to the letter R blocks light and the others transmit light. Similarly 0
Since 2 also corresponds to the sub-modulation means, the pixel corresponding to the letter G blocks light, and the other pixels transmit light. Furthermore, since C1 corresponds to the final regeneration modulation means, image S3 is displayed as is.

Therefore, when C9 to C3 are arranged side by side in the depth direction,
From the front side, there are black letters R and G in front of the blue letter B.
It looks like it's covered over.

Next, when the value of m is time-divisionally changed from 1 to 3 for each field of the image, the three images appear to overlap due to the integration effect caused by the afterimage of the eye, and the image that is actually visible is m as shown in Figure 4. It looks like this when changing by time division.

By the way, the above explanation is about an image seen from a single viewpoint position on the front side. Here, if the viewpoint position is on the left side facing this display device, the geometric positional relationship between each liquid crystal type light modulating plate and the viewpoint position is such that the position shown in FIG. 5(a)
It seems. Similarly, when the viewpoint position is on the right side, the image appears as shown in FIG. 5(b). This figure 5 (a) (b
) as images visible to the left and right eyes when viewing with both eyes, it is clear from the figure that binocular parallax occurs. Also, the fifth
If we consider that the diagram shows the change in appearance that occurs when the viewpoint position is moved, motion parallax is clearly occurring. In this way, a stereoscopic image with motion parallax can be displayed without glasses.

(Effects of the invention) This is a conventional method. In the method of pasting a lenticular lens or a vertical grid on the display, the visible resolution is (1/number of viewpoints) compared to the resolution of the display, resulting in a significant decrease in resolution.

Furthermore, since the image appears unnatural at a certain viewpoint position, there is a problem in that observation positions are limited.

However, in the device of the present invention, since a plurality of images corresponding to parallax are multiplexed in the depth direction, the resolution does not decrease. In addition, the phenomenon of unnatural appearance at a certain viewpoint, which was a problem with conventional devices, has been solved.
In principle, this does not occur with the device of the present invention.

By using the present invention in this way, there is no reduction in resolution,
It is possible to realize stereoscopic images without glasses with natural motion parallax and fewer restrictions on the viewpoint position.

In addition, the display device has a simpler configuration than the configuration of the “stereoscopic image display device” filed by the applicant earlier with the same purpose and submitted to the Japan Patent Office on December 8, 1989.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the basic configuration of the display device of the present invention, Fig. 2 is a diagram showing the configuration of an embodiment, and Fig. 3 is a diagram showing an example of an image signal and a background signal in an embodiment of the present invention. Figure 4 is a diagram for explaining how a stereoscopic image is displayed when the present invention is used. Figure 5 is a diagram for explaining how a stereoscopic image is displayed in an embodiment of the present invention. FIG. 6 is a diagram for explaining conventional stereoscopic vision, and FIG. 7 is a diagram showing an example of conventional image arrangement. Q1-Q,... Two-dimensional light modulation means 31-S,... Image signal R1-Rn-1...
Background signal...Light source CD...Control device for two-dimensional light modulation means C3-C3...
・Liquid crystal light modulation plates D1 to D3...Output image MPD...Multiplexer COL! T...Three-value counter DPS...Display surface VMS...Vertical lattice surface P...Image 1st pattern bright display Fissure core base five formations, 2nd drawing R, 8th 3rd drawing You'''1 No. hi Kiyo\ is a word name 1 Ida 1 (C) picture I 猷 irogo S3 100 S5 figure I (way \ 2 east ro tachi neto picture ii ku! L Ero down b ・ image visible Image 6

Claims (1)

[Claims] 1. A stereoscopic image display device, which includes a plurality of two-dimensional light modulation means capable of controlling light shielding or transmission for each pixel, and displays a stereoscopic image,
A stereoscopic image display device comprising a two-dimensional light modulation means control device that controls a plurality of the two-dimensional light modulation means arranged in parallel in the depth direction. 2. The display device according to claim 1, wherein the two-dimensional light modulation means control device selects one of the plurality of two-dimensional light modulation means as a main modulation means. However, the main modulation means displays the image, the two-dimensional light modulation means located further from the main modulation means transmits the light, and the two-dimensional light modulation means located closer to the main modulation means transmits the light. A stereoscopic image display device characterized in that light is blocked based on a separately generated background signal, and all two-dimensional light modulation means are controlled in a time-division manner to serve as main modulation means.