JPH08160354A - Stereoscopic image display device - Google Patents

Abstract

PURPOSE: To obtain a stereoscopic image display device by a time parallel and space division stereoscopic image display which can be observed by many people at the same time and capable of attaining the miniaturization of the device without necessitating special spepctacles. CONSTITUTION: A Fresnel convex lens 2 is arranged so as to output a stereoscoplc image, and behind the lens 2, a monochromatic liquid crystal television 3 with no analyzer is arranged at, or, near a position where an observer's face image is substantially formed, a television camera 6 is arranged near the Fresnel convex lens 2 so as to input the observer's face image, besides, a color liquid crystal panel 1 capable of displaying the stereoscopic image to be observed by the observer in space division manner is installed between the observer and the Fresnel convex lens 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic image display device which does not require the use of glasses or the like.

[0002]

2. Description of the Related Art Conventionally, the present inventor has already proposed in Japanese Patent Laid-Open No. 6-225344 as a stereo image display device capable of simultaneous observation by a large number of people without using glasses. This device
A color liquid crystal panel that can display a pair of stereo images in a time-division manner and a large image that can be sent selectively to the left and right eyes in order to enable simultaneous observation of stereo images by multiple observers. A time-division head-tracking stereoscopic television composed of a convex lens and a backlight device composed of a black and white television capable of displaying an image of an observer, and enables a large number of people to simultaneously observe a pair of stereo images without glasses.
However, since this device is a time-division system, it is not desirable that image flicker inevitably occurs. To make this a time-parallel system without flicker, a half mirror or a liquid crystal projector must be used. However, it has a drawback that the device becomes larger than the time-sharing method.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is an object of the present invention to provide a small stereoscopic image display device for performing stereoscopic stereoscopic image display in parallel in time without special glasses. It is what

[0004]

The above-mentioned object is achieved by the following (1), and preferably (2) to (8).

(1) A light-transmitting spatial modulation element for displaying a stereo image, a backlight device for illuminating the spatial modulation element from the back surface, and illumination light of the backlight device for an observer. An optical element for distributing to each of the left and right eyes, the spatial modulation element displays each of the stereo images on the same screen so as to have different polarization transparency, and the backlight device has a polarization generation region. A stereoscopic image display device, which is variable and emits two polarized illumination lights having a polarization axis that is at least equal to the polarization transparency of each of the stereo images.

(2) The stereoscopic image display device according to (1), wherein the optical element is any one of a convex lens, a Fresnel convex lens, a holographic convex lens, a diffraction grating lens, a monofoc lens or a concave mirror.

(3) The spatial modulation element is a color liquid crystal image display plate, and the right eye image or the left eye image display portion of the stereo image is substantially evenly distributed to each pixel of the spatial modulation element. The stereoscopic image according to (1) or (2), characterized in that a polarization azimuth rotation member is arranged or attached to the illumination light input surface or the stereo image output surface of either one of the display portions. Display device.

(4) It is further characterized by further comprising a television camera capable of continuously photographing an image on the observer side (1)
(3) The stereoscopic image display device described in (3).

(5) The polarized light generation region for the right eye and the polarized light generation region for the left eye of the backlight device are determined based on a face image of an observer photographed by the television camera (4). Stereoscopic image display device.

(6) When inputting the face image on the side of the observer to the backlight device, the observer image obtained from the television camera is image-modulated so as to input a binarized image of the face of the observer. Alternatively, the stereoscopic image display device according to (4) to (5) is characterized by performing image processing.

(7) A mirror or a half mirror is installed between the backlight device and an observer, and the television camera is installed in an optical axis direction divided by the mirror or the half mirror ( 4) thru | or the stereoscopic image display apparatus of (6) description.

(8) The stereoscopic image display device according to any one of (1) to (7), wherein the backlight illumination light from the optical element is formed into an image by using an autofocus technique.

[0013]

According to the present invention, with the above-described structure, the spatial modulation elements such as liquid crystal are spatially divided in parallel in time so as to act as a backlight for each stereo image displayed so as to have different polarization characteristics. A backlight device having a variable polarization generation region, which is previously arranged behind the optical element, generates at least two polarized illumination lights in which the polarization generation region for the right eye and the polarization generation region for the left eye have respective polarization characteristics of the stereo image. By driving so that each stereo image is distributed to the left and right eyes in parallel in time.

In the present invention, the stereo image means a pair of images for the right eye and the image for the left eye, and displaying in parallel in time means displaying the pair of images in parallel at the same time.

The backlight device emits illumination light by dividing the area into a polarization area for the right eye and a polarization area for the left eye. It is desirable to track each area to the position of the observer.For example, a half-face image of the right face of the observer is photographed by a television camera, and the obtained right-face half face image is polarized for the right eye. Illumination light having the same polarization axis as the right-eye stereo image is emitted as an area, and the remaining area (the peripheral area of the right face half-face image) is used as the left-eye polarization area and having the same polarization axis as the left-eye stereo image. It can be made to emit light.

Further, it is desirable that the polarization characteristics for the right eye and the polarization characteristics for the left eye are orthogonal to each other, but there is no particular limitation as long as they are different.

[0017]

Embodiment 1 FIG. 1 is a perspective view showing the structure of a stereoscopic image display apparatus according to Embodiment 1 of the present invention. In FIG. 1, 1 is a transmission type color liquid crystal plate, and 2 is a color liquid crystal plate 1 as a spatial modulation element for displaying stereo images on the same screen in parallel in time so as to have polarization transmission characteristics orthogonal to each other.
150mm focal length as an optical element located on the back side of
The Fresnel convex lens 3 is a black and white liquid crystal television as a backlight device, and is installed at a position farther than the focal length of the Fresnel convex lens 2 and 160 mm away from the Fresnel convex lens 2. Reference numeral 4 is a stereo image output device such as a video tape recorder, and 5 is a matrix circuit for processing a stereo video signal output from the stereo image output device 4, and a stereo image is displayed on the same screen on the color liquid crystal plate 1 in parallel in time. To output. Reference numeral 6 is an infrared television camera for capturing a face image of an observer who observes a stereoscopic image, 7 is an image processing device for performing image processing on the face image captured by the television camera 6, and 8 is a right face of the observer. An infrared light is used for illumination, and 9 is a housing that houses the main parts of these systems.

In the present embodiment, the monochrome liquid crystal television 3 is
A general liquid crystal television without a polarizing plate provided as an analyzer is used. In a general black and white liquid crystal television, the normal light that enters from the back as a backlight is polarized by a horizontal polarizing plate, and the polarization axis is rotated vertically as the density of the displayed image decreases, and the analyzer at the time of output By passing through (a polarizing plate having a vertical polarization axis),
Backlight does not pass through high density areas, and backlight light passes through low density areas (bright areas).
It becomes possible to display an image. Since the black-and-white liquid crystal television 3 of the present embodiment does not have this analyzer, it operates as a light emitting device having the same brightness in both the high density portion and the low density portion and different in the polarization axis direction. Here, the image displayed on the black and white liquid crystal television 3 is a vertically inverted half-image obtained by binarizing the half-face image of the right face of the observer illuminated by the infrared light 8 with the infrared television camera 6 by the image processing device 7. This is a mirror image, and as a result, the portion corresponding to the right face of the observer on the display surface of the black and white liquid crystal television 3, that is, the right-eye polarization generating region performs light emission display having a polarization axis in the vertical direction, and the other portions. That is, the left-eye polarized light generation region performs light emission display having a horizontal polarization axis.

FIG. 2 is an optical path diagram showing an optical path when the stereoscopic image display device is viewed from above, and FIG. 3 is a diagram showing a state of a display screen of the monochrome liquid crystal television 3. 2 and 3, the black and white liquid crystal television 3 emits light having a vertical polarization axis in the regions corresponding to the half-face images Ar and Br of the right faces of the viewers A and B, and includes Al and Bl. This region emits light having a horizontal polarization axis. This time,
The region Ar is focused by the Fresnel convex lens 2 on the right eye of the observer A, and the region Al is focused by the Fresnel convex lens 2 on the left eye of the observer A. Similarly, the region Br is focused on the right eye and the region Bl is focused on the left eye of the observer B. Therefore,
Light having a vertical polarization axis is incident on the right eyes of the viewers A and B, and light having a horizontal polarization axis is incident on the left eyes. Stereo image for the left eye is displayed so as to have a polarization transmission characteristic in the vertical direction, and a stereo image for the left eye is displayed so as to have a polarization transmission characteristic in the horizontal direction. Can be seen, and the stereo image for the left eye can be seen by the left eye, whereby the stereoscopic image can be observed.

FIG. 4 shows the structure of the color liquid crystal plate 1 shown in FIG. 1 on the incident surface of the backlight, where 50 is the rear surface of the liquid crystal panel display surface and 50a is the liquid crystal panel display surface 5.
Of the pair of stereo images to be displayed at 0, the right-eye image display portion and 50b are the left-eye image display portion of the pair of stereo images, and are alternately arranged for each pixel in the horizontal direction of the color liquid crystal plate 1. It is arranged. Reference numeral 51 is a polarizing plate mounted on the back surface of the liquid crystal panel display surface 50, and 51a is
A polarized portion having polarized light transmission characteristics in the direction indicated by 52a,
Reference numeral 51b denotes a polarization portion having a polarization transmission characteristic in a direction orthogonal to 52a, as indicated by 52b.
1b are alternately arranged in a strip shape, and are polarized portions 51a.
Is aligned with the display portion 50a of the image for the right eye,
By aligning the polarized portion 51b with the display portion 50b for the left-eye image, the right-eye image is output with the same polarization characteristics (vertical direction) as 52a, and the left-eye image is 52.
The image is output with the same polarization characteristic (horizontal direction) as b.
Here, although 50a, 50b and 51a, 51b are alternately arranged for each pixel in the horizontal direction, the same effect can be obtained even if these are alternately arranged for each pixel in the vertical direction. The stereo video signal output from the stereo image output device 4 in FIG. 1 in a time division manner is input to the matrix circuit 5. At this time, since the stereo video signal includes an image for the right eye and an image for the left eye by the interlace method, the right eye The image for driving drives the pixels of the color liquid crystal television 1 in the position where the polarizing plate that can select the right-eye backlight light is driven, and the image for the left eye is for the color liquid crystal television 1 where the polarizing plate that can select the left-eye backlight light exists. Drive the pixel.

Here, the distance y between the Fresnel convex lens 2 and the monochrome liquid crystal television 3 is the focal length f of the Fresnel convex lens 2.
And the distance x between the observer's planned observation position and the color liquid crystal plate 1 x
It is preferable to make a determination based on the calculation formula y = fx /
By determining by (xf), the display surface of the black and white liquid crystal television 3 is located on the focal plane of the Fresnel convex lens 2 for the observer, and acts as a backlight with higher brightness. In this embodiment, it is assumed that the position of the observer is 2400 mm away from the color liquid crystal plate 1. The Fresnel convex lens 2 may be a large convex lens, a holographic lens, a diffraction grating lens, a monofoc lens, or a concave mirror to obtain the same effect.

Further, an autofocus camera is used as the television camera 6, and the distance y between the Fresnel convex lens 2 and the display surface of the black and white liquid crystal television 3 is synchronized with the focus adjustment drive, and the face image of the observer is displayed on the black and white liquid crystal television 3. It may have a function of automatically adjusting so as to form an image on the display surface, and in order to improve efficiency as a backlight, a large convex lens, Fresnel convex lens, holographic lens, diffraction grating on the display surface of the black and white liquid crystal television 3. A lens or a monofocal lens may be provided separately from the Fresnel convex lens.

The television camera 6 may be arranged by using a half mirror or the like so as to be aligned with the optical axis of the Fresnel convex lens 2. In addition, the infrared light 8 may be visible light or ultraviolet light as long as the sensitivity of the television camera 2 can capture the infrared light 8, and the position of the infrared light 8 is arbitrary as long as it is within the scope of the present invention and will be described later. It is not always necessary when performing image processing. Further, if the position of the observer is detected using a detection device using microwaves or ultrasonic waves and image processing is performed based on the detected position to determine the display area of the black and white liquid crystal television 3, the television camera 6 is not always necessary.

Further, the display area of the black and white liquid crystal television 3 does not necessarily have to be based on the half-face image of the face of the observer, and may be a binarized image that acts as a proper backlight for stereo image distribution to the left and right eyes of the observer. Good. Furthermore, 2
A plurality of television cameras 6 may be used to obtain a binarized image, or a video image of an observer may be image-processed to obtain a binarized image.

Here, in this embodiment, the left and right conditions of the viewer's facial image taken by the television camera 6 and the polarization direction conditions of the monochrome liquid crystal television 3 and the color liquid crystal plate 1 are merely examples, and The same effect can be obtained by exchanging.

Regarding the polarizing plate on the backlight incident surface side of the color liquid crystal plate 1, the sticking shape of the film made of crystal or liquid crystal in the polarizing plate is arbitrary within the range not departing from the gist of the present invention, and the polarizing plate The plate may be installed on the display surface side of the color liquid crystal plate 1.

In this embodiment, one-way communication from the video tape recorder is used by inputting from the input terminals 14a, 14b or 15, but two-way communication such as multimedia, game machine or videophone is also used. good.

[0028]

Since the present invention is configured as described above, the position of the observer is not restricted in the observable region, and small-sized and special glasses are not required, and simultaneous observation by a large number of people is possible. It is possible to realize a three-dimensional image display device by displaying a time-parallel and space-divided stereo image.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of a stereoscopic image display device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an optical path of the stereoscopic image display device according to the first embodiment of the present invention when viewed from the upper side surface.

FIG. 3 is a diagram showing a state of a display surface of the monochrome liquid crystal television 3 according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a color liquid crystal plate 1 in Example 1 of the present invention.

[Explanation of symbols]

 1 Color Liquid Crystal Plate 2 Fresnel Convex Lens 3 Black and White Liquid Crystal Television 4 Stereo Image Output Device 5 Matrix Circuit 6 Infrared Television Camera 7 Image Processing Device 8 Infrared Light 9 Housing A, B Observers Ar, Br Polarization Generation Areas Al, Bl For Left Eyes Polarization area

Claims (6)

[Claims] 1. A light modulating spatial modulator for displaying a stereo image, a backlight device for illuminating the spatial modulator from the back surface, and illumination light of the backlight device for the left and right sides of an observer. Optical elements for respectively distributing to the eyes, the spatial modulation element displays each of the stereo images on the same screen so as to have different polarized light transmittance, and the backlight device has a variable polarization generation region. And a stereoscopic image display device which emits two polarized illumination lights having a polarization axis at least equal to the polarization transparency of each of the stereo images. 2. The stereoscopic image display device according to claim 1, wherein the optical element is any one of a convex lens, a Fresnel convex lens, a holographic convex lens, a diffraction grating lens, a monofoc lens or a concave mirror. 3. The spatial modulation element is a color liquid crystal image display plate, and among the stereo image, a right-eye image display area or a left-eye image display portion is approximately evenly distributed to each pixel of the spatial modulation element. On the input surface of the illumination light or the stereo image output surface of one of the display portions,
3. The stereoscopic image display device according to claim 1, wherein a polarization azimuth angle rotating member is provided or attached. 4. The stereoscopic image display device according to claim 1, further comprising a television camera capable of continuously capturing an image on the observer side. 5. The polarization generation region for the right eye and the polarization generation region for the left eye of the backlight device are determined based on a face image of an observer photographed by the television camera. Stereoscopic image display device. 6. When an observer-side face image is input to the backlight device, an observer image obtained from the television camera is image-modulated or input in order to input a binarized image of the observer's face. 6. The stereoscopic image display device according to claim 4, wherein image processing is performed.