JPH1010468A - Stereoscopic picture display system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize and simplify a device and to prolong the life of the device by temporally changing the deflection angle of luminous flux by a deflection means and spatially moving an observed virtual image back and forth. SOLUTION: When the frequency of a sound wave applied from a transducer 23 is changed, a phase diffraction interval generated in an acoustooptical medium is changed and the diffracted light is deflected to perform scanning in an acoustooptical element 22. A controller 30 controls the driving frequency of the transducer 23 and changes the displayed picture on the CRT 31 synchronizing with the control thereof. When the driving frequency of the transducer 23 is made high to make the frequency of the sound wave high, the phase diffraction grating interval (pitch) becomes small and a diffraction angle (deflection angle) becomes large. When the deflection angle becomes large, the luminous flux to eyeballs 32 and 33 comes near to the inside and the picture is viewed in the distance by convergence. Meanwhile, when the frequency of the sound wave is made low, the pitch becomes rough and the deflection angle becomes small, and the luminous flux to the eyeballs 32 and 33 comes near to the outside and the picture is viewed nearby on the contrary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for displaying a stereoscopic image, and more particularly to a system for displaying a stereoscopic moving image by scanning an image in space using one display device.

[0002]

2. Description of the Related Art Conventionally, it has been known that a single display device is used to spatially scan an image to reproduce a stereoscopic image. FIG. 2 is a diagram showing an example in which a three-dimensional image is reproduced by moving the flat panel display back and forth and using an afterimage of a human eye. The flat display device 1 is moved back and forth at a predetermined speed within a reproduction space 3 by a driving device 2. When the flat display device 1 displays, for example, a red pattern at a front end position close to the observer and a blue pattern at a farthest rear end position, increasing the speed at which the display device is moved back and forth will cause the observer to have an afterimage. As a result, it appears that the red picture is at the front end position and the blue picture is at the rear end position, and is reproduced as a stereoscopic image.

However, the apparatus shown in FIG. 2 requires a large scale to move the flat panel display. Therefore, a method as shown in FIG. 3 is also known. FIG. 3 is a diagram showing an example of reproducing a stereoscopic image using a varifocal mirror (a mirror having a variable focal length). The varifocal mirror 5 is configured such that the curvature of the mirror can be periodically changed at a predetermined speed by an electric or mechanical force. Observer is CRT6
When the screen is viewed by the reflected light of the varifocal mirror 5, the screen of the CRT moves away or approaches according to the change in the curvature of the varifocal mirror 5. Therefore, when a red pattern, a blue pattern, and the like are displayed on the screen of the CRT in synchronization with the change in the curvature of the varifocal mirror 5, FIG.
They look three-dimensional as in the case of.

[0004] Further, as shown in FIG. 4, there is also known one provided with a blazed diffraction grating on one eye. FIG. 4 (a)
, The spectacles 7 are through spectacles, and the spectacles 8 are spectacles on which a blazed diffraction grating is formed. Glasses 8
As shown in FIG. 4B, the diffraction angles are different for the R, G, and B lights. As shown in FIG. 5, when viewing the printed matter 9 on which the monochromatic patterns R, G, and B of red, green, and blue are printed with such glasses, in the glasses 8, the light from the red pattern R Since L _R is observed as a broken line L _R ′ by diffraction, the red picture R is observed as a broken line at the position 10 due to binocular parallax. Also, the light L _B from the blue pattern _B
Is observed as a broken line L _B ′ by diffraction, so that the blue pattern B is observed at the position 11 as shown by the broken line due to the binocular parallax. Although not shown, a green pattern is observed at an intermediate position between red and green. As described above, the binocular parallax for a colored pattern differs due to the wavelength dispersion characteristics of the blazed diffraction grating. Red is observed at a far position, blue is at a near position, and green is at an intermediate position, and a stereoscopic image is reproduced. Is done.

[0005]

However, FIG.
The one shown in FIG. 3 requires mechanical scanning and driving, which leads to an increase in the size and complexity of the device, a problem in that vibrations are generated, and the life is relatively short due to the use of movable parts. Further, what is shown in FIGS. 4 and 5 is only a pseudo stereoscopic view in which the depth differs depending on the color.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and aims at miniaturization, simplification and long life of the device.
It is an object of the present invention to provide a stereoscopic image display system capable of perfect stereoscopic viewing.

[0007]

The present invention comprises a display device,
An optical system having means for deflecting a light beam from the display device,
A control unit that controls the display device and the deflection unit in synchronization with each other, and changes a deflection angle of the light beam by the deflection unit with time;
The virtual image to be observed is spatially moved back and forth.

[0008]

Embodiments of the present invention will be described below. FIG. 1 is a diagram illustrating an example of a stereoscopic image display system according to the present invention. The system of the present invention includes the control device 3
By controlling the spectacles 20 and the CRT 31 with 0, the polarization angle and the image are changed in synchronization with each other, thereby enabling complete stereoscopic vision. In FIG. 1A, the glasses 20 include two prisms 21, two acousto-optic elements 22, and two transducers 23 for driving the acousto-optic elements. The acousto-optical element 22 is a transducer 23
When the frequency of the sound wave (or ultrasonic wave) applied from the optical disk is changed, the interval between the phase diffraction gratings generated in the acousto-optic medium changes, and the deflection scanning of the diffracted light becomes possible.

The control device 30 controls the driving frequency of the transducer 23 and synchronizes with the driving frequency of the
The display image 31 is changed.

The control device 30 controls the transducer 23
When the frequency of the sound wave is increased by increasing the driving frequency of the laser beam, the interval (pitch) of the phase diffraction grating is reduced, and the diffraction angle (deflection angle) is increased. When the deflection angle becomes large, FIG.
In the example of (1), the luminous flux for the eyeballs 32 and 33 moves inward, and the image is seen far away due to convergence. On the other hand, when the frequency of the sound wave is reduced, the pitch becomes coarse, the deflection angle becomes small, and the luminous flux to the eyeballs 32 and 33 looks outward and appears close. The prism 21 is used to adjust a neutral image forming position, and at the same time, is set so that zero-order light does not enter the eyeball. Since the diffraction grating has a different diffraction angle depending on the wavelength, the display image is desirably a single color. For this purpose, it is desirable to display a single color, or to insert a filter so that only monochromatic light is guided to the glasses.

In this example, the CRT 31 has a diagonal of 14 inches and the display image is a single red color. Assuming a depth of 10 cm as a three-dimensional space, 14 inches diagonal x 10 cm by computer graphics (CG) technology
A single color moving image data in the space was prepared.

The control device 30 synchronizes the sectional images scanned in the depth direction of the three-dimensional space one after another on the screen of the CRT 31 so that the acousto-optic device 22 of the glasses 20 has a deflection angle corresponding to the depth. The frequency corresponding to the pitch of the diffraction grating was given. By repeating the above scanning every time the frame changes, a stereoscopic moving image could be observed.

As shown in FIG. 1B, when images are displayed cyclically in the order of red → green → blue → red... In synchronization with the change of the deflection angle, the images of the respective colors appear with a perspective. You can do so.

In the above description, an acousto-optic effect element is used as a deflector. However, the present invention is not limited to this, and an optical deflector using an electro-optic effect element whose refractive index changes with an electric field is used. It is also possible to use.

[0015]

As described above, according to the present invention, mechanical driving and scanning are not required, so that the apparatus can be miniaturized and simplified, and at the same time, the generation of vibration can be suppressed and the life can be extended. Can be achieved. Further, by synchronizing and changing the deflection angle and the image, perfect stereoscopic vision becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a stereoscopic image display system according to the present invention.

FIG. 2 is a diagram illustrating an example in which a flat display device is moved back and forth, and a stereoscopic image is reproduced using an afterimage of a human eye.

FIG. 3 is a diagram illustrating an example of reproducing a stereoscopic image using a varifocal mirror.

FIG. 4 is a diagram illustrating an example of a stereoscopic device provided with a blazed diffraction grating in one eye.

FIG. 5 is an explanatory diagram of a stereoscopic view using a blazed diffraction grating.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Flat display device, 2 ... Drive device, 3 ... Reproduction space, 5 ...
Vari-focal mirror, 6 CRT, 7 through-glasses, 8 glasses with blazed diffraction grating, 9 printed matter, 20 glasses, 21 prism, 22 acousto-optic element, 23 transducer, 30 Control device, 31 ...
CRT, 32 ... left eye, 33 ... right eye.

Claims (6)

[Claims] 1. A display device, comprising: an optical system having a deflecting means for deflecting a light beam from the display device; and a control means for controlling the display device and the deflecting means in synchronization with each other. A stereoscopic image display system characterized in that a virtual image to be observed is moved back and forth spatially by changing a deflection angle of a light beam due to time. 2. The stereoscopic image display system according to claim 1, wherein said deflecting means is an acousto-optic effect element or an electro-optic effect element. 3. The stereoscopic image display system according to claim 1, wherein the light beam guided from the display device to the optical system having the deflecting means is a single color. 4. The stereoscopic image display system according to claim 1, wherein an image displayed on the display device changes in synchronization with a change in the deflection angle by the deflection means. 5. The stereoscopic image display according to claim 1, wherein the optical system is spectacles, and the binocular parallax is changed by temporally changing the deflection angle of the light beam by the deflecting means. system. 6. The stereoscopic image display system according to claim 1, wherein the optical system has a prism.