JP2966782B2 - 3D image display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional image display device using a specular reflection type optical modulator, which can be used to view high-intensity three-dimensional display images and reduce the number of parts.
The present invention relates to a three-dimensional image display device whose configuration can be simplified.

[0002]

2. Description of the Related Art Conventionally, as a stereoscopic image display device, as shown in FIG. 12, for example, light emitted from a light source 1 is made incident on a polarization beam splitter 2 to be split into two lights of P-wave light and S-wave light. Then, the P-wave light passes through, for example, the liquid crystal panel 14 that forms a right-eye image and is incident on the projection lens 4,
Another liquid crystal panel that projects light from the projection lens 4 onto the right-eye pixel R of the screen 5 and rotates the S-wave light into P-wave light by, for example, rotating the phase difference film 15 by 90 ° and then forming, for example, a left-eye image 16 to enter the projection lens 17, and from the projection lens 17 to the left-eye pixel L of the screen 5.
Projected to

When a lenticular lens 18 and a parallax barrier are arranged before, after, or before and after the screen 5 where images projected from the projection lenses 4 and 17 are connected, the lenticular lens 18 and the parallax barrier are arranged. The left-eye image and the right-eye image are separated by a barrier or the like, and the observer can view the stereoscopic image by viewing the corresponding images with the left and right eyes.

[0004] Further, the retardation film 15 is omitted,
A left-eye image composed of P-wave light and a right-eye image composed of S-wave light are formed on the screen 5, and an observer views the corresponding images with left and right eyes while wearing polarized glasses to view a stereoscopic image. Some have made it possible.

Meanwhile, recently, a large number of minute mirrors are arranged in a matrix on one plane, and by changing the direction of the mirrors, a mirror reflection type in which light reflected in a predetermined direction is turned on / off. Optical modulators have been developed.

Further, the specular reflection type light modulator is irradiated with incident lights of two or more colors from different incident angles, and the tilt direction of a mirror constituting each pixel of the specular reflection type light modulator is controlled by time division. A projector device (refer to Japanese Patent Application Laid-Open No. 7-209621) that reflects two or more colors of incident light in the same direction, thereby enabling color synthesis of each pixel, and three specular reflection type light modulators are used. A projector device in which a red image, a green image or a blue image formed by each specular reflection type optical modulator is synthesized by a prism and a color image is projected through a projection lens (Japanese Patent Laid-Open No. 7-36012).
Reference) has been proposed.

However, a stereoscopic image display device using the specular reflection type optical modulator has not been found so far.

[0008]

According to the above-mentioned stereoscopic image display apparatus using a liquid crystal panel, there is a problem that a large amount of light is lost in the liquid crystal panel and the screen looks dark. or,
Since two liquid crystal panels are used, two systems of image forming means including a liquid crystal panel and a means for controlling the liquid crystal panel are required, and the number of parts is large, and the configuration tends to be complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a three-dimensional image display device using a specular reflection type optical modulator with small light loss.

[0010]

In order to achieve the above object, a stereoscopic image display apparatus according to the present invention has a light source, a polarizing beam splitter for separating light from the light source into P-wave light and S-wave light, and a polarizing beam splitter. The P-wave light and the S-wave light separated by the splitter are incident from different directions, and an image of the P-wave light is formed in each pixel displaying one of the left-eye image and the right-eye image, and is formed in a predetermined direction. A specular reflection light modulator that forms an image of s-wave light at each pixel that reflects and displays the other image and reflects the light in the predetermined direction, and an image of p-wave light reflected by the specular reflection light modulator And a projection lens for projecting an image of the S-wave light on the screen.

According to the present invention, the light emitted from the light source is split into the P-wave light and the S-wave light by the polarization beam splitter, and the P-wave light and the S-wave light pass through separate optical paths to the specular reflection type optical modulator. Incident.

The specular reflection type optical modulator includes a large number of micromirrors arranged in a matrix. Each micromirror has a flat state in which the reflection surface faces the projection lens, and a state in which the reflection surface is inclined to one side. By switching to the state inclined to the opposite side, light incident from two different directions can be reflected in the direction of the projection lens.

Therefore, if the minute mirror corresponding to the black point of the left-eye image is in a flat state and the minute mirror corresponding to the white point is tilted in the direction of the S-wave, for example, the left-eye image of the S-wave light can be obtained. Is formed and emitted in the direction of the projection lens, the micro mirror corresponding to the black point of the right-eye image is set to a flat state, and the micro mirror corresponding to the white point is set to the other side, for example, P
If the state is inclined in the direction of the wave, an image for the right eye of the P wave light is formed and emitted in the direction of the projection lens.

In this way, a left-eye image and a right-eye image are formed, and when the left-eye image and the right-eye image are reflected in the predetermined direction of the specular reflection type optical modulator, The left-eye image and the right-eye image are enlarged and projected on the screen by the projection lens arranged on the reflected light path.

The observer can view a stereoscopic image by viewing the left-eye image and the right-eye image formed on the screen using the polarizing glasses. In addition, the left-eye image and the right-eye image are imaged such that the left-eye image pixels and the right-eye image pixels are alternately arranged on the screen, and the left and right images are formed by a lenticular lens or a parallax barrier. Separation allows viewing of stereoscopic images without glasses.

Each pixel of the specular reflection type optical modulator is a pixel forming a left-eye image (hereinafter, referred to as a left-eye pixel) and a pixel forming a right-eye image (hereinafter, a right-eye pixel). ), For example, pixels for the left eye and pixels for the right eye are arranged alternately every vertical line, alternately arranged every horizontal line, or alternately in a checkered pattern. Or can be arranged side by side.

When the pixels for the left eye and the pixels for the right eye are alternately arranged as described above, the pixels for the left eye and the pixels for the right eye are exchanged in a time-division manner in order to increase the spatial resolution. Is also possible. Of course, the formation of the left-eye image and the formation of the right-eye image can be alternately performed in a time-division manner by all the pixels.

Each pixel of the specular reflection type optical modulator can be rotated around a rotation axis set in the pixel so that reflection of light in a predetermined direction can be turned ON / OFF. I have. The rotation axis of each pixel may be parallel,
The rotation axis of the pixel for the left eye and the rotation axis of the pixel for the right eye may be directed in directions intersecting each other. When the rotation axis of the pixel for the left eye and the rotation axis of the pixel for the right eye are arranged in parallel, on the plane perpendicular to the rotation axis, the P-wave light and S-wave light enters and is reflected in the direction of the reflected optical axis. When the rotation axis of the left-eye pixel and the rotation axis of the right-eye pixel are arranged so as to intersect with each other, on the plane perpendicular to each rotation axis, the same is applied from the reflection optical axis to the projection lens. P from the direction inclined by the angle
Wave light and S-wave light enter and are reflected in the direction of the reflected optical axis.

The left-eye image and the right-eye image are not limited to black and white images, but may be color images. In the case of displaying a color stereoscopic image, for example, a rotating color filter that switches three primary colors or a time-division color separating device that combines a dichroic mirror and a liquid crystal shutter is arranged between a light source and a polarizing beam splitter. The left-eye pixel and the right-eye pixel of the specular reflection light modulator may be turned on / off in accordance with each color image in accordance with the color switching timing of the filter or the time-division color separation device.

By the way, the left-eye image and the right-eye image projected on the screen follow different optical paths, and may be shifted from each other. This shift is not a problem when observing a stereoscopic image, but when the observer observes a planar image without wearing polarizing glasses, this shift causes a reduction in resolution. Therefore, at the time of displaying a plane image, it is preferable to block either one of the P-wave light and the S-wave light so that the image is not double-projected on the screen. Further, in this case, if an image is formed using all the pixels of the specular reflection type optical modulator, the number of pixels is twice as large as that in displaying a three-dimensional image, so that the observer is twice as many as in displaying a three-dimensional image. It is possible to appreciate a screen having brightness.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. As shown in the principle diagram of FIG. 1, a stereoscopic image display apparatus according to an embodiment of the present invention includes a light source 1, and separates light emitted from the light source 1 into P-wave light and S-wave light polarized by 90 °. A polarization beam splitter 2, a P-light beam and a S-wave beam which are incident from different directions and reflected in the same direction, and a P-light beam and a P-light beam reflected by the specular reflection light modulator 3. A projection lens 4 for enlarging and projecting the S-wave light onto the screen.

As shown in the perspective view of FIG. 2, the specular reflection type optical modulator 3 has a large number of micromirrors arranged at appropriate intervals in the horizontal and vertical directions. For example, as shown in FIG. 3, a left-eye pixel L or a right-eye pixel R is formed alternately for each horizontal line.

As shown in FIG. 2, when the left-eye image becomes 0FF, the reflection surface of the left-eye pixel L is in a flat state in which the reflection surface faces the front. Is inclined in the first direction obliquely upward, and the incident S
Wave light is reflected in the front direction. That is, the left-eye image is ON
, The left-eye pixel L corresponding to the white point of the left-eye image tilts in the first direction and reflects the incident S-wave light in the front direction, while the left eye corresponding to the black point of the left-eye image. Pixel L
Becomes flat, a left-eye image is formed on the screen from the projection lens 4.

When the right-eye image is turned off, the right-eye pixel R is in a flat state in which the reflection surface faces forward,
When turned ON, the reflecting surface rotates in the second direction obliquely downward around the rotation axis indicated by the broken line, and reflects the incident P-wave light in the front direction.

Light incident on the left-eye pixel L in the flat state is reflected in a direction reverse to the optical path of the right-eye image, and
The light incident on the right-eye pixel R in the flat state is reflected in a direction reverse to the optical path of the left-eye image, but none of the light is reflected in the front direction, so that the image quality of the image formed on the screen is reduced. There is no danger of lowering.

The light reflected from the pixel L for the left eye and the light reflected from the pixel R for the right eye are incident on the projection lens 4, and an image for the left eye and an image for the right eye are displayed on a screen. By observing, a stereoscopic image is seen.

The light emitted from the light source 1 passes through the polarizing beam splitter 2 and is reflected and projected by the reflecting mirror 6 and the pixel L for the left eye or the pixel R for the right eye of the specular reflection type optical modulator 3. Since the light is incident on the lens 4, light loss is significantly reduced as compared with a case where a liquid crystal panel is interposed between the polarizing beam splitter 2 and the projection lens 4, and the brightness of an image can be increased.

In addition, compared to the case where two liquid crystal panels are used, only one mirror reflection type optical modulator needs to be controlled, so that the number of parts can be reduced and the size can be reduced. The configuration including the control means for the simplification is simplified.

In FIG. 1, for convenience of explanation, the P-wave light or the S-wave light separated by the polarizing beam splitter 2 is reflected by one reflecting mirror 6 and enters the specular reflection type optical modulator 3. However, since the incident angles of the P-wave light and the S-wave light are limited in accordance with the rotation angle of each pixel of the specular reflection type optical modulator 3, the polarization beam splitter 2 and the specular reflection type light are actually used. A more complicated optical system, for example, an optical system in which two mirrors 6a and 6b are interposed, as shown in FIG.

In this embodiment, as shown in FIG.
The left-eye pixels L and the right-eye pixels R are alternately arranged for each horizontal line to increase the resolution in the horizontal direction. For example, as shown in FIG. And the right-eye pixel R to increase the vertical resolution.
For example, as shown in FIG. 5, a left-eye pixel L and a right-eye pixel R
May be arranged in a checkered pattern. When the pixels L for the left eye and the pixels R for the right eye are arranged in a checkered pattern as described above, the resolution is advantageously increased in both the horizontal and vertical directions.

Further, in the above embodiment, as shown in FIG. 2, the rotation axis of the left-eye pixel L and the rotation axis of the right-eye pixel R of the specular reflection type optical modulator 3 are parallel to each other. But
For example, as shown in FIG. 6, the rotation axis of the pixel L for the left eye and the rotation axis of the pixel R for the right eye may be directed in directions intersecting each other. In these embodiments, as shown in FIG. 2 or FIG. 6, the rotation axis of the left-eye pixel L or the right-eye pixel R is oriented in the horizontal direction or the vertical direction.
Alternatively, as shown in FIG. 8, a rotation axis may be set on a diagonal line of the pixel L for the left eye or the pixel R for the right eye.

The incident direction of the P-wave light or the S-wave light is not particularly limited. However, in order to increase the reliability of the operation, along the plane perpendicular to the rotation axis of the micro mirror and the rotation angle of the micro mirror. It is preferable that the light be incident on the micromirror in a flat state by twice the angle from a direction inclined from a vertical axis.

In another embodiment of the present invention shown in FIG. 9, a lens 7 for converging the light of the light source 1 between the light source 1 and the polarizing beam splitter 2, a rotating color filter 8, A lens 9 for converting light transmitted through the rotating color filter 8 into parallel light. The switching frequency of the three primary colors of RGB of the rotating color filter 8 is set to, for example, 180 Hz which is three times as large as that of the monochrome display, and the mirror reflection type optical modulator is driven in synchronization with the frequency to display a color stereoscopic image.

In another embodiment of the present invention shown in FIG. 10, four dichroic mirrors 11 and two total reflection mirrors 12 are used in place of the rotary color filter 8 of the previous example.
And a time-division color separation device 10 in which three liquid crystal shutters 13 are combined.
The RGB primary color switching frequency of 0 is set to, for example, 180 Hz, which is three times that of the monochrome display, and the mirror reflection type optical modulator 3 is driven in synchronization with the frequency to display a color stereoscopic image.

[0035]

As described above, the present invention provides a light source, a polarizing beam splitter for separating light from the light source into P-wave light and S-wave light, and a P-beam light and an S-wave light separated by the polarizing beam splitter. Is incident, the P-wave light is reflected in a predetermined direction from each pixel displaying one of the left-eye image and the right-eye image, and the S-wave light is reflected from each pixel displaying the other image. A specular reflection type optical modulator that reflects light in a predetermined direction, and P wave light and S light reflected by the specular reflection type light modulator
Wave light is incident, and a projection lens for projecting the P-wave light image and the S-wave light image on a screen is provided. Therefore, light loss between the polarizing beam splitter and the projection lens is reduced by interposing a liquid crystal panel therebetween. And the brightness of the video can be increased.

Further, since the left-eye image and the right-eye image can be formed by using one specular reflection type optical modulator,
Compared to the conventional example in which a left-eye image and a right-eye image are formed using two liquid crystal panels, the number of parts can be reduced and the size can be reduced. The configuration can be simplified, including the control means for the control.

[Brief description of the drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is a perspective view showing the operation of the specular reflection type optical modulator of the present invention.

FIG. 3 is a front view showing a pixel array of the specular reflection type optical modulator of the present invention.

FIG. 4 is a front view showing another pixel arrangement of the specular reflection type optical modulator of the present invention.

FIG. 5 is a front view showing still another pixel array of the specular reflection type optical modulator of the present invention.

FIG. 6 is a perspective view showing the operation of another specular reflection type optical modulator of the present invention.

FIG. 7 is a perspective view of another specular reflection type optical modulator according to the present invention.

FIG. 8 is a perspective view of still another specular reflection type optical modulator according to the present invention.

FIG. 9 is a perspective view showing a configuration of a main part of another embodiment of the present invention.

FIG. 10 is a configuration diagram of a main part of still another embodiment of the present invention.

FIG. 11 is a configuration diagram illustrating an actual configuration of one embodiment of the present invention;

FIG. 12 is a configuration diagram of a conventional example.

[Description of Signs] 1 Light source 2 Polarizing beam splitter 3 Specular reflection type light modulator

Claims (4)

(57) [Claims] 1. A light source, a polarization beam splitter for separating light from a light source into P-wave light and S-wave light, and a P-wave light and an S-wave light separated by the polarization beam splitter are incident from different directions from each other to form an image for the left eye. And an image of P-wave light is formed on each pixel displaying one image of the right-eye image and reflected in a predetermined direction, and an image of S-wave light is formed on each pixel displaying the other image. And a projection lens for projecting the P-wave light image and the S-wave light image onto a screen. 2. The rotation axis of each pixel forming one of the left-eye image and the right-eye image of the specular reflection type optical modulator and the rotation axis of each pixel forming the other image are mutually different. The pixels are arranged in parallel, and each pixel is in a flat state directly facing the projection lens when the pixel is off, and each pixel displaying one of the left-eye image and the right-eye image is in this flat state when on. The three-dimensional image display device according to claim 1, wherein each pixel that is tilted in a first direction and displays the other image is tilted in a second direction opposite to the first direction when turned on. 3. The rotation axis of each pixel for displaying one of the left-eye image and the right-eye image of the specular reflection optical modulator, and the rotation axis of each pixel for displaying the other image. The three-dimensional image display device according to claim 1, wherein the three-dimensional image display device is oriented in directions intersecting each other. 4. A time-division color separation device combining a rotary color filter or a dichroic mirror and a liquid crystal shutter is disposed between a light source and a polarization beam splitter, and a specular reflection type optical modulator is rotated by a rotation color filter or a time-division color filter. The three-dimensional image display device according to claim 1, wherein time-division driving is performed in synchronization with color switching of the separation device.