JPH0990276A - Picture display device and stereoscopic picture display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stereoscopic picture display device which eliminates the need for glasses provided with a function of dividing light between right and left by installing a back light device provided with a light emitting device and visual field selecting glass for giving a directivity to light emitted by the light emitting device, and selectively making the light emitted by the light emitting device incident on either of observer's right and left eyes through the visual field selecting glass. SOLUTION: The back light device 3 is constituted of the visual field selecting glass 4, the light emitting device 5 and a light reflecting part 6. As for the picture display device 1, the picture is observed by the observer's one eye, then, the device is used for a visual power testing device, etc. The visual field selecting glass 4 functions so that the light whose incident angle is equal to or exceeding a specified angle may be transmitted through the glass 4, the light whole incident angle is below the specified angle may be reflected, or not transmitted, and in this case, the glass 4 is formed to a saw-tooth shape by adjusting the angle so that only the light advancing toward observer's right eye may be transmitted and the glass may be vertical to a line linking with observer's right eye. Thus, the observer can view the picture on the display 2 only by his right eye, not by his left eye.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device and a stereoscopic image display device used for industrial, home or medical purposes.

[0002]

2. Description of the Related Art As a conventional stereoscopic image display device, an observer wears spectacles having a function of distributing left and right to display stereo images for the right eye and the left eye which are time-divisionally displayed on an image display surface. Those that can be observed only by the right and left eyes of the observer, respectively, or a lenticular plate is attached to the image display surface, the image distribution function of the lenticular plate, a stereo image for the right eye and the left eye It is general that the above can be observed only by the right and left eyes of the observer.

FIG. 7 shows the structure of a stereoscopic image display device in the first conventional example, in which 60 is spectacles having a left / right distribution function, 61a and 61b are liquid crystal shutters,
62 is a synchronizing circuit, 63 is a color CR as an image display device.
T.

The operation of the conventional three-dimensional image display device configured as described above will be described. Color CRT 63
, The stereo images for the right eye and the left eye are alternately displayed in a time division manner. The liquid crystal shutter 61a of the spectacles 60 opens and becomes transparent only when the right-eye stereo image is displayed, and the liquid crystal shutter 61b opens and transmits only when the left-eye stereo image is displayed. By controlling the open / closed state by the synchronizing circuit 62 so that the state becomes the state, the observer wearing the spectacles 60 observes only the stereo image for the right eye with the right eye and only the stereo image for the left eye with the left eye. Stereoscopic vision is performed by observing.

Further, the present applicant has filed Japanese Patent Application Laid-Open No. 7-140418.
Proposed a device that selectively observes an image on the left and right eyes of an observer by using a convex lens, but this device is unavoidable because the depth of the device is not less than the focal length of the lens. There is a problem that the device becomes large.

[0006]

However, according to the study by the present inventors, in the conventional stereoscopic image display device as described above, the stereoscopic image is independently observed by the right and left eyes of the observer. For this reason, eyeglasses having a left / right distribution function have been indispensable.

It is an object of the present invention to provide a stereoscopic image display device which does not require glasses having a left / right distribution function.

Another object of the present invention is to provide an image display device which can be miniaturized.

[0009]

In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention is a spatial modulation element for displaying an image, and for illuminating the spatial modulation element from the back side. An image display device including a backlight device is characterized in that the backlight device has a light emitting means and a field-of-view selection glass for giving directivity to light emitted from the light emitting means.

Here, as the spatial modulation element, a color liquid crystal device or the like can be cited as a display device having a light transmitting property.

The invention according to claim 2 of the present invention is
It is characterized in that the field-of-view selection glass selectively allows the light emitted from the light emitting means to enter into either the left or right eye of the observer.

Here, the means for allowing the field-of-view selection glass to selectively enter the light emitted by the light emitting means into either of the left and right eyes of the observer is the observer at a predetermined observation position among the light emitted by the light emitting means. This can be done by designing the field-selection glass so that it only transmits light that is directed toward one eye.

The invention according to claim 3 of the present invention is
3. The image display device according to claim 2, wherein the image display device comprises two sets, and the image display devices of the two sets further include a synthesizing unit for synthesizing display images, each of the two image display devices being an observer. The light emitted from the light emitting means is selectively incident on each of the left and right eyes of the.

A beam splitter such as a half mirror may be used as a synthesizing means for synthesizing the display images of the two sets of image display devices.

The invention according to claim 4 of the present invention is
The field-of-view selection glass is for entering different polarized light into the right eye and the left eye of the observer respectively, and the spatial modulation element displays the image for the right eye and the image for the left eye in different pixels, respectively, and Each of them has a polarization transmission characteristic matching the polarized light for the right eye and the polarized light for the left eye emitted from the backlight device.

Here, as means for allowing the field-of-view selection glass to enter different polarized lights into the right and left eyes of the observer, the field-of-view selection glass is installed so as to have a sawtooth-like surface shape, and one of the sawtooths is provided. It is conceivable to attach a polarization filter having a polarization transmission characteristic in the X direction to the surface of the slope and a polarization filter having a polarization transmission characteristic in the Y direction to the other slope. Further, in order to impart polarization transmission characteristics matching the right-eye and left-eye polarizations to each pixel of the spatial modulation element, a polarization filter having polarization transmission characteristics in the X direction and the Y direction is similarly provided on the surface of the spatial modulation element. The image for the right eye is displayed on the pixel to which the polarization filter in the X direction is attached, and the image for the left eye is displayed to the pixel to which the polarization filter in the Y direction is attached.

The invention according to claim 5 of the present invention is
The light emitting means is independently provided behind the field of view selection glass that allows light to enter the observer's right eye or left eye, and among the light emitting means, one for the right eye and one for the left eye are time-shared. Are alternately emitted, and the spatial light modulator alternately displays the right-eye image and the left-eye image in time division in synchronization with the time division.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a perspective view showing the structure of an image display apparatus 1 according to Embodiment 1 of the present invention, and FIG. 2 is a view showing how the apparatus of FIG. 1 is observed. In FIG. 1 and FIG. 2, 2 is a transmissive color liquid crystal display as a spatial modulation element, 3 is a backlight device, which is composed of a field-of-view selection glass 4, a light emitting means 5, and a light reflecting section 6.

The operation of the above image display device will be described with reference to FIGS. 1 and 2. The image display device according to the first embodiment is a device intended for observing an image with only one eye of an observer, and may be used as a visual acuity test device or the like. In FIG. 1, an image observed by an observer with only one eye (the right eye in the first embodiment) is displayed on the color liquid crystal display 2.

The field-of-view selection glass 4 allows light having an incident angle of light (angle formed by a light beam and the surface of the glass) of a specific angle or more to pass therethrough, and reflects light having an angle of less than that or not. In the first embodiment, the saw tooth is adjusted by adjusting the angle so as to be perpendicular to the line connecting to the right eye side of the observer so that only the light traveling to the right eye side of the observer is transmitted. Form.

The light emitting means 5 is composed of a fluorescent lamp, and the light reflecting portion 6 composed of a mirror plate spreads light of various angles over the entire field selection glass 4.

Here, the image displayed on the color liquid crystal display 2 does not emit light by itself, so that it cannot be seen by an observer unless it is illuminated by a backlight. Therefore, with the above-described configuration, the backlight device 3 irradiates light so that only the right eye of the observer can see, so that the observer observes the image displayed on the color liquid crystal display 2 only with the right eye and the image with the left eye. Will not be observable.

(Embodiment 2) FIG. 3 is a perspective view showing the structure of a stereoscopic image display apparatus according to Embodiment 2 of the present invention. Example 2
In the above, two sets of the above-described device of the first embodiment are prepared for the left and right sides, and the left and right eyes are made to observe different images (stereo images with parallax) by combining them by using a combining means. In FIG. 3, 7 is a stereoscopic image display device main body, and 8 is a half mirror as a synthesizing means. Reference numeral 1a is a right-eye image display device similar to that of the first embodiment, and 1b is a left-eye image display device, and the configurations of both are basically the same.

The operation of the above stereoscopic image display apparatus will be described with reference to FIG. The right-eye image display device 1a is the same device as that of the first embodiment as described above, and displays the image to be observed by the observer's right eye (“right” in FIG. 3) on the color liquid crystal display 2a. Since the backlight device 3a of the image display device for the right eye 1a allows light to enter only the right eye of the observer as in the first embodiment, only the right eye of the observer observes the image for the right eye.

The image display device 1b for the left eye is installed with the stereoscopic image display device 7 facing downward, and the color liquid crystal display 2b is an image to be observed by the observer's left eye (FIG. 3).
Is displayed in consideration of being reflected by the half mirror 8. Therefore, at that time, the lower side of the image is set to the front side for the observer, and the image is displayed as a mirror image. As the backlight device 3b, the same device as the backlight device 3a of the right-eye image display device 1a may be installed by changing the left and right directions.

As described above, since the observer observes the right-eye image with his right eye and the left-eye image with his left eye, he can observe a stereo image without glasses.

(Embodiment 3) FIG. 4 is a view showing a manner of observing a stereoscopic image display device 9 according to Embodiment 3 of the present invention. FIG.
In the figure, 10 is a transmissive color liquid crystal display as a spatial modulation element, 11 is a backlight device, and the field-of-view selection glass 12, the light emitting means 13a and 13b, and the light reflection portion 1 are provided.
4 Polarization filters 15 and 16 are attached to the back surface of the color liquid crystal display 10 and the front surface of the backlight device 11, respectively. FIG. 5 is a diagram schematically showing the state of the deflection filter 15, showing the color liquid crystal display 10 as viewed from the back side.

The operation of the above image display device will be described with reference to FIGS. 4 and 5. The color liquid crystal display 10 is
An image for the right eye and an image for the left eye are displayed alternately for each column of pixels. The polarization filter 15 includes pixels 5 for displaying an image for the right eye.
A filter element 51a having a polarization azimuth angle in the X direction is provided on the back surface of 0a, and a filter element 51b having a polarization azimuth angle in the Y direction (which is different from the X direction by 90 degrees) is provided on the back surface of the pixel 50b displaying an image for the left eye. Are provided to be arranged.

In the backlight device 11, each of the right slope and the left slope of each sawtooth tooth of the field-of-view selection glass 12 is
The angle is set so that only light directed to the observer's right and left eyes is transmitted. Further, on the respective surfaces of the right slope and the left slope of each of the sawtooth-shaped teeth of the view selection glass 12,
The polarization filter 16 is attached. The polarization filter 16 has an X on the slope that transmits the backlight light for the right eye.
The azimuth angle of the azimuth direction is set, and the inclined surface that transmits the backlight light for the left eye is installed so as to have the azimuth angle of the Y direction. In addition, in the first and second embodiments, one light emitting device is provided in one backlight device, but in the third embodiment, one backlight device 11 provides a backlight for the left and right eyes. Since it is necessary to cover, two light emitting means 13a and 13b are provided for the purpose of increasing the amount of light. To prevent the generation of scattered light and obtain an increase in the amount of light by using, for the field-of-view selection glass 12, light having an incident angle of light of a specific angle or more is transmitted and light of an angle of less than that is reflected. You can

With the above configuration, the backlight device 11
Irradiates the observer's right eye with polarized light in the X direction and illuminates the observer's left eye with polarized light in the Y direction. When the color liquid crystal display 10 is illuminated by the backlight with polarized light in the X direction, only the image for the right eye can be observed, and Y
Only the left-eye image can be observed by being illuminated by the backlight with the polarized light in the direction. Therefore, since the observer observes the image for the right eye with the right eye and the image for the left eye with the left eye, the observer can observe the stereo image without glasses.

(Embodiment 4) FIG. 6 is a view showing a manner of observing a stereoscopic image display device 17 according to Embodiment 4 of the present invention. In FIG. 6, reference numeral 18 is a transmissive color liquid crystal display as a spatial modulation element, 19 is a backlight device, and field-of-view selection glasses 20a and 20b and light emitting means 21a and 21b.
And are arranged alternately.

The operation of the above stereoscopic image display device will be described with reference to FIG. Stereo images (right-eye image, left-eye image) are alternately displayed on the color liquid crystal display 18 in a time division manner. The backlight device 19 is synchronized with the time division, and when the right-eye image is displayed, the light emitting means 21a.
Is emitted, and when the image for the left eye is displayed, the light emitting means 2
1b is made to emit light, and blinking is repeated alternately. The plurality of light emitting means 21a and 21b are partitioned so as not to affect the adjacent field-of-view selection lens, respectively.
When each of them emits light, the field-of-view selection lens 21a transmits only the light of this light directed to the right eye of the observer. Further, when each of the light emitting means 21b emits light, the field-of-view selection lens 21b transmits only the light of this light directed toward the left eye of the observer.

Therefore, the backlight device emits light so that only the right eye of the observer can see when the color liquid crystal display 18 displays the right eye image, and when the color liquid crystal display 18 displays the left eye image, Since the light is emitted so that only the left eye of the observer can see it, the observer can observe the stereo image.

[0035]

As described above, according to the configuration of the present invention, it is possible to obtain an apparatus capable of observing a stereoscopic image without glasses, and further, since a lens optical system is not used, it is thin. A stereoscopic image display device can be obtained.

[Brief description of drawings]

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

FIG. 2 is a configuration diagram of an image display device in Embodiment 1 of the present invention.

FIG. 3 is a perspective view of a stereoscopic image display device according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a stereoscopic image display device according to a third embodiment of the present invention.

FIG. 5 is a diagram showing a state where the color liquid crystal display 10 of the stereoscopic image display device in Embodiment 3 of the present invention is viewed from the back side.

FIG. 6 is a configuration diagram of a stereoscopic image display device according to a fourth embodiment of the present invention.

FIG. 7 is a diagram illustrating a conventional stereoscopic image display device.

[Explanation of symbols]

 1: Image display device 2: Color liquid crystal display 3: Backlight device 4: Field-of-view selection glass 5: Light emitting means 6: Light reflection part 7: Stereoscopic image display device 8: Half mirror

Claims (5)

[Claims] 1. An image display device comprising a spatial modulation element for displaying an image and a backlight device for illuminating the spatial modulation element from the back side, wherein the backlight device emits light from a light emitting means and the light emitting means. An image display device having a field-of-view selection glass for giving directivity to light. 2. The image display device according to claim 1, wherein the field-of-view selection glass selectively allows the light emitted from the light emitting means to enter into either the left or right eye of the observer. 3. The image display device according to claim 2, comprising two sets, further comprising a synthesizing unit for synthesizing display images of the two sets of image display devices. A stereoscopic image display device, characterized in that the light emitted from the light emitting means is selectively incident on each of the left and right eyes of an observer. 4. The image display apparatus according to claim 2, wherein the field-of-view selection glass makes the right eye and the left eye of the observer respectively enter different polarized lights, and the spatial modulation element respectively forms an image for the right eye and an image for the left eye. A three-dimensional image display device, wherein the three-dimensional image display device displays different pixels, and each of the pixels in the spatial light modulator has a polarization transmission characteristic matching the right-eye and left-eye polarizations emitted by the backlight device. 5. The light emitting means in the image display device according to claim 2, wherein the light emitting means are independently provided behind a field of view selection glass that allows light to enter the observer's right eye or left eye. , The right eye and the left eye are alternately made to emit light in a time division manner, and the spatial light modulator alternately displays the right eye image and the left eye image in a time division manner in synchronization with the time division. A stereoscopic image display device characterized by the above.