JPH09146043A - Stereoscopic video display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display stereoscopic video with high luminance, to decrease the number of components, and to simplify the constitution. SOLUTION: A stereoscopic image is composited and displayed on a screen by a mirror surface reflection type optical modulator 5 which is equipped with many fine mirror surface elements 7 whose reflecting surfaces have >=3 tilt angle stable states and imposes time-division modulation according to video data of >=2 systems, a couple of reflecting mirrors 9L and 9R for left-eye video and right-eye video reflected at different angles by the said mirror surface reflection type optical modulator 5 as to the illumination light from a light source 1, and projection lenses 10L and 10R.

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 equipped with a specular reflection type optical modulator, and in particular, it can display a high brightness stereoscopic image and can reduce the number of parts and simplify the structure. The present invention relates to a stereoscopic image display device that can be performed.

[0002]

2. Description of the Related Art Conventionally, as a stereoscopic image display device, for example, as shown in FIG. 11, light emitted from a light source 1 is made incident on a polarization beam splitter 2 and separated into two lights, P-wave light and S-wave light. Then, the P-wave light is transmitted through the liquid crystal panel 18 for forming an image for the right eye and is incident on the projection lens 4,
Another liquid crystal panel for projecting from the projection lens 4 to the right-eye pixel R of the screen 5, rotating the S-wave light by 90 ° by the retardation film 19 to polarize it into P-wave light, and then forming, for example, a left-eye image. The light is transmitted through 20 to enter the projection lens 21, and the projection lens 21 causes the pixel L for the left eye of the screen 5 to pass through.
Is projected on.

When a lenticular lens 22, a parallax barrier, etc. are arranged in front of, behind, or in front of or behind the screen 5 on which images projected from both projection lenses 4 and 21 are connected, these lenticular lens 22 and parallax are arranged. The image for the left eye and the image for the right eye are separated by a barrier or the like, and an observer can view a stereoscopic image by viewing the corresponding images with the left and right eyes.

Further, the phase difference film 19 is omitted,
A stereoscopic image is viewed by forming a left-eye image composed of P-wave light and a right-eye image composed of S-wave light on the screen 5, and allowing an observer to wear polarized glasses to view the corresponding images with the left and right eyes. Some are made available.

By the way, recently, a large number of minute mirrors are arranged in a matrix on one plane and the direction of these mirrors is changed to turn on / off the light reflected in a predetermined direction. Reflective light modulators have been developed.

Further, the specular reflection type optical modulator is irradiated with incident light of two or more colors from different incident angles, and the tilt directions of the mirrors constituting each pixel of the specular reflection type optical modulator are time-division controlled. A projector device (see Japanese Patent Laid-Open No. 7-209621) and three specular reflection type optical modulators are used, which are capable of reflecting two or more colors of incident light in the same direction and thereby performing color combination of each pixel. A projector device in which a red image, a green image or a blue image formed by each specular reflection type light modulator is combined by a prism and a color image is projected through a projection lens (JP-A-7-36012).
(See Japanese Patent Publication).

However, no stereoscopic image display device using this specular reflection type light modulator has been found so far.

[0008]

According to the stereoscopic image display device using the above-mentioned liquid crystal panel, there is a problem that the light loss in the liquid crystal panel is large 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 means for controlling the liquid crystal panel are required, and the number of parts is large and the structure tends to be complicated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a stereoscopic image display device equipped with a specular reflection type optical modulator with a small optical loss.

[0010]

In order to achieve the above-mentioned object, a stereoscopic image display device equipped with a first specular reflection type optical modulator according to the present invention has a stable reflection angle of three or more. A specular reflection type optical modulator including a large number of minute specular surface elements, which are modulated in a time-division manner according to image data of two or more systems, and illumination light incident on the specular reflection type optical modulator from a certain direction. Light source and two or more projection optical systems that project image data reflected from the specular reflection type light modulator at different angles with respect to the illumination light onto a screen.
Two or more systems of image data projected on the screen through the two or more projection optical systems are combined on the screen to display a stereoscopic image.

The light source is reflected by, for example, a polarization beam splitter so as not to overlap with the projection optical system, and is incident on the specular reflection type optical modulator. Light incident on the specular reflection type optical modulator is reflected by each micro mirror surface element, and two or more projection optical systems are formed that transmit through the polarization beam splitter at different angles corresponding to the tilt angle of each micro mirror surface element. .

Here, the light transmitted from the light source through the polarization beam splitter is provided with a reflection mirror facing the polarization beam splitter and the light source in the direction opposite to the light source of the polarization beam splitter, and reflected by this reflection mirror. It can be reused by reflecting it toward the light source side, then re-reflecting it at the light source, and emitting it toward the polarization beam splitter.

Further, another specular reflection type optical modulator is arranged in the direction opposite to the light source of the polarization beam splitter, and the light transmitted through the polarization beam splitter from the light source is used to make a small mirror surface element of this specular reflection type optical modulator. Two or more projection optics for irradiating the screen with image data reflected by the specular reflection type optical modulator at different angles with respect to this illumination light A system can be formed. In this case, since two specular reflection type optical modulators are used, the number of pixels is doubled, the density of image data projected on the screen can be increased, and the image resolution can be increased.

Further, the light from the light source is made incident on the first polarization beam splitter, reflected in the direction perpendicular to the incident direction, and then made incident on the second polarization beam splitter and the third polarization beam splitter and transmitted. The first specular reflection type optical modulator corresponding to the reflected light, the second specular reflection type optical modulator corresponding to the light reflected by the second polarization beam splitter, and the third reflection type optical beam splitter reflected by the third polarization beam splitter. It is possible to further increase the density of the image data projected on the screen and further increase the resolution of the image by providing a third specular reflection type optical modulator corresponding to the light.

The stereoscopic image may be displayed by changing the polarization direction of the image projected on the screen through each projection optical system so that the viewer can observe the stereoscopic image by wearing polarized glasses. The pixels of the image projected on the screen via the system may be alternately arranged on the left and right sides and separated by the lenticular lens or the parallax barrier so that the stereoscopic image can be observed without glasses.

In the stereoscopic image display device using the second specular reflection type optical modulator of the present invention, a large number of minute specular surface elements having two stable states in which the inclination angle of the reflection surface is two are set in accordance with the image data of two or more systems. A specular reflection type optical modulator that is time-divisionally modulated is used. Also in this case, the same incident illumination light is converted into two light beams depending on the two tilt angles from the specular reflection type light modulator.
Although two projection optical systems are formed, these two projection optical systems are selectively turned on and off in order to prevent the image data of the two projection optical systems from overlapping.

This selective ON-0FF is realized, for example, by interposing an optical element having a shutter function in each projection optical system.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The following will specifically describe an embodiment of the present invention with reference to the drawings.

As shown in the principle diagram of FIG. 1, in a stereoscopic image display apparatus according to an embodiment of the present invention, a light source 1 composed of a lamp and a reflector, and light emitted from the light source 1 has a wavelength of λ /.
The light is made incident through the 4 phase difference film 2, a part of the light is transmitted, and the remaining part is 90 ° with respect to the incident direction.
A polarization beam splitter 3 that reflects in different directions, another λ / 4 retardation film 4 that transmits the light reflected by the polarization beam splitter 3, and specular reflection that the light transmitted through the retardation film 4 enters. Type optical modulator 5.

The stereoscopic image display device further comprises a reflecting mirror 6 for reflecting the light transmitted through the polarizing beam splitter 3, the light reflected by the reflecting mirror 6 is transmitted through the polarizing beam splitter 3 again, and λ / The light is incident on the light source 1 through the four-phase retardation film 2 and is reflected again by the reflector of the light source so as to increase the light utilization rate.

The specular reflection type optical modulator 5 is, for example, 67
As shown in FIG. 2, the minute mirror surface element 7 is provided with a number of minute mirror surface elements corresponding to 5 pixels × 576 lines, and the minute mirror surface element 7 is reflected by the polarization beam splitter 3 to form a specular reflection type optical modulator 5.
To the light i incident at right angles, a first tilted state in which the flat state is tilted to the lower left in the figure, and a second tilted state in which the flat state is tilted to the lower right in the figure. It is controlled to be stable in the three states.

The control means 8 for controlling the specular reflection type light modulator 5 is time-divisionally controlled by the specular reflection type light modulator 5 corresponding to two image data of a right eye image and a left eye image. It suffices if it is configured to modulate light. For example, as shown in FIG. 3, an A / D conversion circuit 81 for converting an analog video signal into a digital video signal, and a γ correction circuit for γ correction of this digital video signal. 82, the frame memory 83 for storing the γ-corrected digital video signal, the data of the frame memory 83 is read at the timing generated by the timing controller 84 based on the clock signal given from the clock circuit 84, and the frame memory 83 is read.
The state of the microscopic mirror element 7 is controlled to one of the three states shown in FIG.

For example, the micro mirror element 7 of the pixel for the left eye forming the image for the left eye is in a flat state in which the reflection surface faces the front when the image for the left eye is 0FF, and when it is turned on, the first mirror is used. The tilted state is entered and the incident light is reflected in a first predetermined direction that is tilted counterclockwise from the incident optical axis. That is, when the left-eye image is turned on, the microscopic mirror element 7 (L-0 of the left-eye pixel corresponding to the white point of the left-eye image is displayed).
N) is in the first tilted state and reflects the incident light in the first predetermined tilt direction, while the micro mirror surface element 7 (0FF) of the left eye pixel corresponding to the black point of the left eye image is The image for the left eye emitted in a first predetermined direction is formed by becoming flat and reflecting the incident light as invalid light in the incident direction.

The right-eye pixel R is in a flat state when the right-eye image is OFF, and is in a second tilt state when the right-eye image is ON, so that the incident light is incident on the incident optical axis. It reflects in a second predetermined direction that is tilted clockwise. That is, when the image for the right eye is turned on, the minute specular element 7 (RO) of the pixel for the right eye corresponding to the white point of the image for the right eye.
N) is in the first tilted state and reflects the incident light in the second predetermined tilt direction, while the microscopic mirror element 7 (OFF) of the right eye pixel corresponding to the black spot of the right eye image is turned on. By becoming flat and reflecting the incident light as invalid light in the incident direction, a right-eye image emitted in the second predetermined direction is formed.

The light incident on the minute mirror surface element 7 (OFF) of the left eye pixel in the flat state and the light incident on the minute mirror surface element 7 (OFF) of the right eye pixel in the flat state are the first or second. Since the light is reflected in the direction opposite to the incident direction different from the predetermined direction, there is no possibility that the data of the right-eye image and the data of the left-eye image are mixed and the resolution of the image is deteriorated.

When the specular reflection type light modulator 5 is used, it is possible to form a left-eye image and a right-eye image at the same time, but the spatial stereoscopic resolution is increased by increasing the number of pixels of each image. In order to increase the
It is preferable that the left-eye image and the right-eye image are alternately switched, or that the left-eye image and the right-eye image are alternately formed in all pixels as shown in FIG. 8, for example. In FIG. 8, +1 indicates the time when the image for the left eye is formed, and -1 indicates the time when the image for the right eye is formed.

The stereoscopic image display device further includes the first
In order to project the left-eye image data emitted in the predetermined direction and the right-eye image data emitted in the second predetermined direction on the screen, for example, a pair of left and right mirrors 9
A projection optical system including L / 9R and a pair of left and right projection lenses 10L and 10R is provided.
In this way, a left-eye image and a right-eye image are enlarged and projected on the screen, and both images are combined on a screen (not shown) to enable stereoscopic viewing.

When one of the left-eye image and the right-eye image formed on this screen is formed by P-wave light and the other is formed by S-wave light, the observer wears polarized glasses. A stereoscopic image can be observed from the left-eye image and the right-eye image formed on the screen, and the pixels of the left-eye image and the right-eye image formed on the screen can be moved to the left and right. By alternately arranging and providing a lenticular lens or a parallax barrier, a stereoscopic image can be observed from the left-eye image and the right-eye image formed on the screen without glasses.

What is important here is that a liquid crystal panel with a large light loss is not used in the optical system from the light source 1 to the projection lenses 10L and 10R, and a stereoscopic image is displayed using the liquid crystal panel. That is, it is possible to obtain an image with significantly higher brightness than the conventional example. Further, since only one specular reflection type optical modulator 5 is used, the number of parts can be reduced and the control means 8 can be provided as compared with the conventional example in which two liquid crystal panels are used to form an image. The configuration can be simplified.

In the above-mentioned embodiment, each micro-mirror element 7 of the specular reflection type light modulator 2 is constructed so as to be stable at three positions, but in another embodiment of the present invention, for example, FIG. As shown in, each micro mirror element 7 of the specular reflection type light modulation device 2 is configured to be stable at two positions, that is, the first tilted state and the second tilted state in the previous example.

In this case, the light from the minute mirror surface element 7 which becomes the white point of the image for the right eye or the image on the opposite side to the minute mirror surface element 7 of the image for the left eye or the image for the right eye which should become a black point. May be reflected and disturb the image.

Therefore, in this case, as shown by the broken line in FIG. 1, the shutters 11L and 11R are arranged immediately in front of the projection lenses 10L and 10R, and as shown in FIGS. By alternately turning on and off in synchronization with the driving of the modulator 2, the left and right image data are prevented from being mixed.

In FIG. 8, +1 indicates the time when the image for the left eye is formed, and -1 indicates the time when the image for the right eye is formed. Further, in FIG. 7, when the specular reflection type optical modulator is "H", the time when the image L for the left eye is formed is
It shows the time when the image for the right eye is formed when L ",
SHUTTER L is the shutter 11 for the left-eye image
It indicates that it is closed when it becomes "H" and opened when it becomes "L". Or, the shutter 1 for the image for the right eye.
1 indicates that SHUTTER R is closed when it goes to "H" and opened when it goes to "L".

The other structure, operation and effect of this embodiment are the same as those of the above-described embodiment, and therefore, description thereof will be omitted to avoid duplication.

In another embodiment of the invention shown in FIG. 9,
Another λ / 4 retardation film 1 instead of the reflecting mirror 6 in the previous example
2 and a specular reflection type optical modulator 13 are arranged so that the light transmitted through the polarization beam splitter 3 can be used to output another image data in an overlapping manner on the two projection optical systems. The two specular reflection type optical modulators 5 and 13 may be driven in synchronization with each other or may be driven alternately in a time division manner.

Thus, the two-face specular reflection type optical modulator 5
If the number 13 is used, the number of pixels of the left-eye image and the right-eye image can be increased to make the image high-definition, and the luminance of the image can be further increased.

Since the other construction, operation and effect of this embodiment are the same as those of the above-mentioned one embodiment, their description will be omitted to avoid duplication.

In yet another embodiment of the present invention shown in FIG. 10, the light reflected by the polarization beam splitter 3 is split into three directions by a dichroic prism 15, and each split light is a specular reflection type. Light modulator 5
14 and 17 face each other. Each specular reflection type optical modulator 5
Reference numerals 14 and 17 form left-eye images and right-eye images of the three primary colors of R, G, or B, and emit them to the above-mentioned two projection optical systems.

A color filter corresponding to the λ / 4 phase difference film 4.13.16 is arranged between the dichroic prism 15 and each specular reflection type optical modulator 5.14.17.

Further, as in the embodiment of FIG. 1, the λ / 4 phase film 2 is provided between the polarization beam splitter 3 and the light source.
Is arranged, and further, a reflecting mirror 6 for reflecting the light transmitted through the polarization beam splitter 3 is arranged to improve the light utilization efficiency.

According to this embodiment, by driving the specular reflection type light modulators 5, 14, 17 in a synchronized or time-division manner, color images for the left and right eyes are displayed on the screen. The stereoscopic color image can be viewed using polarizing glasses or using a lenticular lens or a parallax barrier.

Since the other constructions, functions and effects of this embodiment are the same as those of the above-mentioned one embodiment, their description will be omitted to avoid duplication.

[0043]

As described above, according to the present invention, a large number of micro mirror elements having a stable state in which the inclination angle of the reflecting surface is three or more are provided, and the time division is performed according to the image data of two or more systems. A modulated specular reflection type light modulator, a light source that makes illumination light enter the specular reflection type light modulator from a certain direction, and this illumination light is reflected from the specular reflection type light modulator at different angles. And a projection optical system that irradiates the screen with the image data that is generated, and the stereoscopic image is synthesized by combining the two or more systems of the video data that are projected onto the screen through the two or more projection optical systems on the screen. I will display it,
Compared to the conventional example in which a liquid crystal panel having a large light loss is interposed between the light source and the projection lens, the light loss is small and a high-luminance image can be observed.

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

[Brief description of the drawings]

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

FIG. 2 is a principle diagram showing an operation of the specular reflection type optical modulator of the present invention.

FIG. 3 is a block circuit diagram of a control circuit of the specular reflection type optical modulator of the present invention.

FIG. 4 is a principle diagram showing an operation of another specular reflection type optical modulator of the present invention.

FIG. 5 is a principle diagram showing an operation at the time of displaying an image for the left eye according to another embodiment of the present invention.

FIG. 6 is a principle view showing an operation at the time of displaying an image for the right eye according to another embodiment of the present invention.

FIG. 7 is a control timing chart of another embodiment of the present invention.

FIG. 8 is a control timing chart of one embodiment and another embodiment of the present invention.

FIG. 9 is a principle view of still another embodiment of the present invention.

FIG. 10 is a principle view of still another embodiment of the present invention.

FIG. 11 is a configuration diagram of a conventional example.

[Explanation of symbols]

 1 Light source 3 Polarization beam splitter 5 Specular reflection type optical modulator 9L, 9R Reflecting mirror 10L / 10R Projection lens

Claims (2)

[Claims] 1. A specular reflection type optical modulator, comprising a large number of minute specular surface elements having a stable state in which a tilt angle of a reflecting surface is three or more, and which is time-divisionally modulated according to image data of two or more systems, A light source that illuminates the specular reflection type light modulator from a certain direction, and two or more light sources that illuminate the screen with image data reflected from the specular reflection type light modulator at different angles. And the projection optical system of
A stereoscopic image display device, characterized in that two or more systems of image data irradiated on a screen through one or more projection optical systems are combined on the screen to display a stereoscopic image. 2. The same incident illumination as a specular reflection type optical modulator in which a large number of minute specular surface elements each having a reflection surface having two stable states are modulated in a time-division manner according to image data of two or more systems. Two projection optical systems that are selectively turned on and off in accordance with two tilt angles from the specular reflection type light modulator with respect to light are provided, and the two projection optical systems are irradiated onto the screen through the two projection optical systems. A stereoscopic image display device characterized by displaying stereoscopic images by synthesizing video data of systems or more on a screen.