JPH08160448A - Picture display device - Google Patents

Abstract

PURPOSE: To realize a picture display device high in resolution and small in size at a low cost. CONSTITUTION: This device has an optical address type liquid crystal light valve 4, a writing LCD panel 23 and a writing light source 1 and is provided with a picture writing means writing a picture in the liquid crystal light valve 4, a panel moving device 24 making the picture writing position of the liquid crystal valve 4 with the picture writing means periodically change by the movement of the writing LCD panel 23, a writing panel driving circuit 7 supplying a picture signal to the writing LCD panel 23 so that the picture corresponding to the picture writing position is written in the position in the liquid crystal valve 4 moved by the operation of the panel moving device 24 and a light source driving circuit 5 and a synchronizing circuit 8 performing the writing operation on the liquid crystal valve 4 with the picture writing means after completions of respective moving operations by moving means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a projection type display,
The present invention relates to an image display device provided in an image processing device, an optical information processing device, or the like.

[0002]

2. Description of the Related Art A conventional image display device includes, for example, a device for projecting and displaying an image written in an optically addressed liquid crystal light valve. This type of device includes the optically addressed liquid crystal light valve. As a means for writing images to the C
There is known one provided with an RT (cathode ray tube) and a flat panel display.

An apparatus for writing an image by a CRT has a structure shown in FIG. That is, the image displayed on the CRT 101 is written on the photoconductor layer of the photo-addressable liquid crystal light valve 103 via the writing lens 102. On the other hand, the light emitted from the light source 105 enters the polarization beam splitter 104. Of the incident light, the P-polarized component passes through the polarization beam splitter 104, and the S-polarized component is bent by the polarization beam splitter 104 at a right angle in the traveling direction and enters the optically addressable liquid crystal light valve 103. The incident light is an optically addressable liquid crystal light valve 103 (hereinafter, simply referred to as a liquid crystal light valve 103).
Is reflected by. In this case, when an image is written in the liquid crystal light valve 103, the polarization state changes in the image-written area due to the electro-optical effect of the liquid crystal, and the P-polarized component is included. Therefore, the reflected light can be transmitted through the polarization beam splitter 104, and this light is projected on the screen 107 via the projection lens 106 to display an image.

The general structure of the liquid crystal light valve 103 is, as shown in FIG. 11, a glass substrate 111a on both sides.
111b, and the transparent electrode 112a, the photoconductor layer 113, and the reflection layer 1 between them from the glass substrate 111a side.
14, alignment film 115a, spacer 116, liquid crystal layer 11
7, an alignment film 115b and a transparent electrode 112b are provided.

The liquid crystal light valve 103 is formed as follows. Transparent electrodes 112a and 112b made of an ITO transparent conductive film on glass substrates 111a and 111b
Is formed by an electron beam evaporation method, and amorphous silicon hydride (a- is formed as a photoconductor layer 113 on the transparent electrode 112a.
Si: H) is formed by the plasma CVD method (chemical vapor deposition method). A dielectric mirror (multi-layered film of titanium oxide / silicon oxide) is formed thereon as the reflection layer 114 by an electron beam evaporation method. Next, after forming a polyimide film as the alignment films 115a and 115b, a molecular alignment treatment by rubbing is performed to attach the glass substrates 111a and 111b to the spacers 1.
Laminate through 16. After that, a liquid crystal light valve 103 is formed by injecting and sealing a ferroelectric liquid crystal or a nematic liquid crystal as the liquid crystal layer 117. As the display mode of the liquid crystal light valve 103, a hybrid electric field effect (HFE) mode or a surface-stabilized ferroelectric liquid crystal display (SS-FLC) mode is used.

In such a liquid crystal light valve 103, a voltage is applied from the AC power supply 118 between the transparent electrodes 112a and 112b, and the following operation is performed. Glass substrate 111a
When the address light L is incident from the side, the impedance of the photoconductor layer 113 decreases in the light-exposed region (bright state), and the voltage applied from the AC power supply 118 causes the liquid crystal layer 1 to pass.
Join 17 On the other hand, in a region not exposed to light (dark state), the impedance of the photoconductive layer does not change, and the liquid crystal layer 11
No voltage is applied to 8. Due to the difference between the bright state and the dark state, image information corresponding to the address light L is formed on the liquid crystal layer 118.

Therefore, in the configuration shown in FIG. 10, C
An image can be written in the liquid crystal light valve 103 by RT, and display can be performed using the liquid crystal light valve 103.

A device for writing an image on a flat panel display is disclosed in Japanese Patent Laid-Open No. 2-13122.
As disclosed in No. 1, there is one using an electroluminescent element as an image writing means. This device has a photo-addressable liquid crystal light valve including a photoconductive layer, a light absorption layer, a light reflection layer, and a liquid crystal layer, and has an electroluminescent element integrally formed outside the write electrode. There is.

Here, as a method for increasing the resolution of the image display device, in the CRT, the number of pixels is increased by increasing the number of scanning lines and the number of driving lines to realize a high resolution of HDTV and the like. . As another method, in Japanese Utility Model Laid-Open No. 6-48285, an image display element is driven by an actuator at an amplitude of 1/2 pixel pitch in synchronization with an image signal supplied to an image display element such as an LCD, A technique has been disclosed in which an image signal shifted by an amount of movement is given in synchronization with the vibration of an image display element to allow a viewer to synthesize and recognize these images by an afterimage phenomenon to achieve high resolution.

[0010]

From the above, the resolution of the image display device using the photo-addressable liquid crystal light valve can be increased to a high resolution type for the CRT or the electroluminescent element which is the image writing means. It can be realized by using However, the high-resolution type image writing means is very expensive as compared with the normal resolution type, which causes an increase in the cost of the image display device. In addition, the size of the image writing means whose resolution has been increased by increasing the number of pixels becomes large, and when writing at the same size from the image display means to the liquid crystal light valve, it is necessary to increase the panel size of the liquid crystal light valve. Yes, the cost will increase. Further, in this configuration, when a small liquid crystal light valve is used, a reduction optical system is required between the image writing unit and the liquid crystal light valve, which causes an increase in cost and also the image writing unit and the liquid crystal. There is a problem that the size of the device combined with the light valve becomes large, and the image display device becomes large in size. Further, also in a direct-view type device for a normal CRT or the like, when the resolution of a display device such as a CRT is increased, similarly, a large cost increase is caused.

Further, as disclosed in Japanese Utility Model Laid-Open No. 6-48285, when a high resolution is achieved by vibrating an image display device having a normal resolution, a large screen of the display device is used. An image display device is required. As a result, the weight of the image display element is inevitably increased, resulting in an increase in the size and weight of an actuator for vibrating the image display element, resulting in a problem that the display device is increased in size.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an image display device which can easily realize miniaturization, high resolution and large screen without causing a significant increase in cost.

[0013]

In order to solve the above-mentioned problems, the image display device according to the invention of claim 1 has at least a photoconductor layer and a liquid crystal layer between a pair of translucent substrates having electrodes. And an image writing unit having an image writing element in which pixels are arranged two-dimensionally, and a light emitting source for writing, and an image writing unit for writing an image in the optical address light valve. Moving means for periodically moving the image writing position of the optical address type light valve by the image writing means by the movement of the image writing means, and the image writing position of the optical address type light valve moved by the operation of the moving means, Image signal supplying means for supplying an image signal to the image writing element so that an image corresponding to this position is written, and each moving operation by the moving means is completed. To, is characterized by comprising a write driving means for causing a write operation to the optical address type light valve by the image writing means.

An image display device according to a second aspect of the present invention is the image display device according to the first aspect, wherein the photo-addressable light valve has an image holding function.

An image display device according to a third aspect of the invention is the image display device according to the first or second aspect of the invention, characterized in that the moving means moves the writing light emitting source.

An image display device according to a fourth aspect of the present invention is the image display device according to the first to third aspects, characterized in that the image writing means comprises an electroluminescent element.

[0017]

According to the structure of the first aspect, when the image writing means writes an image on the optical address type light valve, the image writing position of the optical address type light valve by the image writing means moves the image writing means. Thus, after the completion of each movement, the image corresponding to that position is written at the moved image writing position in the photo-addressable light valve.

Therefore, the display image by the photo-addressable light valve has a high resolution due to the afterimage phenomenon of the eyes of the viewer even when the low-resolution image writing element is used. As a result, an expensive high-resolution type image writing element, for example, a CRT having a large number of scanning lines and driving lines
It is possible to realize high resolution of the image display device without incurring a significant cost increase such as the use of.

In this case, since the size of the display screen can be increased by using the projection optical system for projecting the image of the optical address type light valve, a small image writing element can be used. As a result, the image display device can be configured without increasing the size of the device in which the image writing element and the photo-addressable light valve are combined. Further, even when moving the image writing element, the actuator may be small. Therefore, a high-resolution and small-sized image display device can be realized.

Further, according to the second aspect of the invention, since the photo-addressable light valve has an image holding function, the resolution of the image display device can be surely improved, and the light on the reading light side is improved. High-luminance display can be obtained without deterioration in luminance.

According to the third aspect of the invention, the moving means moves the light emitting source for writing. Therefore, for example, the image writing element having a large amount of wiring to another device is moved to improve the resolution. The structure of the moving means can be simplified as compared with the above.

According to the fourth aspect of the invention, since the electroluminescent element having the functions of the image writing element and the light emitting source for writing is used as the image writing means, the number of parts is reduced and the image display device is provided. The configuration of can be simplified.

[0023]

【Example】

[Embodiment 1] An embodiment of the present invention will be described below with reference to FIGS. The image display device of this embodiment is shown in FIG.
, A writing light source 1 as a writing light emitting source, a collimator lens 2, a writing LCD panel device 3, an optical address type liquid crystal light valve 4 (hereinafter, simply referred to as a liquid crystal light valve 4), and a light source as a writing driving means. A drive circuit 5, a panel moving device drive circuit 6, a writing panel drive circuit 7 as an image signal supply means, and a synchronization circuit 8, and a projection lamp 9 and a collimator lens 1 shown in FIG.
0, a polarization beam splitter 11, a projection lens 12 and a screen 13.

The collimator lens 2 collimates the light emitted from the writing light source 1 and guides it to the writing LCD panel device 3.

As shown in FIG. 3, the writing LCD panel device 3 is an image writing element, and the writing LCD panel 2 constitutes an image writing means together with the writing light source 1.
3 and a panel moving device 24 as a moving means. Light from the writing light source 1 that has passed through the collimator lens 2 can enter the writing LCD panel 23. The panel moving device 24 includes an outer frame 21, an inner frame 22, and panel moving parts 25 to 28. The inner frame 22 is provided in the outer frame 21, and Y
It is movable in any direction. Writing LCD panel 2
3 is provided in the inner frame 22 and is movable in the X direction.

The panel moving parts 25 to 28 use a voice coil motor system. The panel moving unit 25
An iron core 25a provided in the central portion in the X direction on the lower surface of the upper frame portion of the outer frame 21, a coil 25b wound around the iron core 25a and forming an electromagnet together with the iron core 25a,
And the iron core 25 in the upper frame portion of the inner frame 22
It is composed of a magnet 25c provided at a position facing a. The panel moving portion 26 is a magnet provided at a position facing the iron core 26a and the coil 26b provided in the central portion in the X direction on the upper surface of the lower frame portion of the outer frame 21, and the iron core 26a at the lower frame portion of the inner frame 22. 26c. The panel moving unit 27 includes an iron core 27 a and a coil 27 b provided in the Y direction central portion on the inner surface of one lateral frame portion of the inner frame 22, and the writing LCD panel 2.
The magnet 27c is provided at a position facing the iron core 27a at the side edge portion of No. 3. The panel moving portion 28 is provided at a position where the iron core 28a and the coil 28b provided in the central portion in the Y direction on the inner surface of the other horizontal frame portion of the inner frame 22 and the iron core 28a at the side edge portion of the writing LCD panel 23 face each other. It is provided with a magnet 28c.

The writing LCD panel 23 is driven in the Y direction by the panel moving units 25 and 26, and the panel moving unit 2
It is driven in the X direction by 7.28. That is, the coil 27
An electric current is applied to the coil b with a polarity such that an attractive force acts between the iron core 27a and the magnet 27c, and the coil 28b is supplied with the iron core 28a and the magnet 2c.
If a current is applied with a polarity such that repulsive force acts between 8c and
The writing LCD panel 23 moves to the left side in FIG. On the other hand, if the polarities of the currents flowing through the coils 27b and 28b are reversed, the writing LCD panel 23 moves to the right side in FIG. By repeating this operation, the writing LCD panel 23 can be vibrated in the X direction. In addition, a current is applied to the coil 25b with a polarity such that an attractive force acts between the iron core 25a and the magnet 25c, and the coil 26b
When a current is applied with a polarity such that a repulsive force acts between the iron core 26a and the magnet 26c, the writing LCD panel 23 moves upward in FIG. On the other hand, the coils 25b and 26b
If the polarity of the current passed through is reversed, the writing LCD panel 23 moves to the lower side in the figure. By repeating this operation, the writing LCD panel 23 can be vibrated in the Y direction. Further, the vibrations in the X direction and the Y direction can be independently performed.

As shown in FIG. 4, the liquid crystal light valve 4 has glass substrates 31a and 31b on both sides thereof, and a transparent electrode 32a, a photoconductor layer 33, and a light shielding layer 34 between these glass substrates 31a from the glass substrate 31a side. , Dielectric mirror 35, alignment film 36
a, a spacer 37, a liquid crystal layer 38, an alignment film 36b, and a transparent electrode 32b are provided. An AC voltage is applied by an AC power supply 39 between the transparent electrodes 32a and 32b. The liquid crystal light valve 4 is formed as follows.

Glass substrates 31a, 31 which are translucent substrates
transparent electrodes 32a and 32 made of an ITO transparent conductive film on b
b is formed to a thickness of 0.2 μm by the sputtering method, and then the transparent electrode 3
A photoconductor layer 33 having a back-to-back diode structure of amorphous silicon hydride (a-Si: H) is formed on 2a. In addition, amorphous silicon tin hydride (a-Si)
A light shielding layer 34 made of Sn: H) is formed. Next, titanium dioxide / silicon dioxide is alternately laminated as the dielectric mirror 35 to form a multilayer film in which a total of 20 layers are laminated. Next, after forming a polyimide film as the alignment films 36b and 36b by a printing method, a molecular alignment treatment by rubbing is performed,
The glass substrates 31a and 31b are bonded together via the spacer 37. After that, a liquid crystal light valve 4 is formed by injecting and sealing a nematic liquid crystal as the liquid crystal layer 38. A hybrid field effect mode is used as the operation mode of the liquid crystal light valve 4.

By using a liquid crystal having a high resistivity of 10 ¹⁰ Ωcm or more as the material of the liquid crystal layer 38, the liquid crystal light valve 4
Can have afterimage property of the written image. Further, by doping impurities (C, B, N, etc.) into a-Si: H of the photoconductor layer 33, the optical attenuation characteristic after the writing light is incident is delayed and the afterimage of the written image is maintained. Can be made. In the liquid crystal light valve 4 of the present embodiment, a-Si:
H was doped with boron (B) as an impurity. Specifically, silane gas (SiH ₄ ) is replaced with diborane gas (B ₂ H
₆ ) The plasma C using 300ppm of mixed gas as a raw material
It was created using the VD method (chemical vapor phase reaction method). As a result, the liquid crystal light valve 4 could have an afterimage property of about 30 msec.

The light source drive circuit 5 turns on and off the writing light source 1 based on a signal from the synchronizing circuit 8. The panel moving device drive circuit 6 acts on the panel moving device 24 of the writing LCD panel device 3 based on the signal from the synchronizing circuit 8 to cause the writing LCD panel 2 to operate.
3 is driven in the Y direction and the X direction orthogonal thereto. The writing panel drive circuit 7 causes the writing LCD panel 23 to display an image corresponding to a drive position due to vibration based on a signal from the synchronizing circuit 8. The synchronizing circuit 8 synchronizes the light source driving circuit 5, the panel moving device driving circuit 6 and the writing panel driving circuit 7 as described later.

The collimator lens 10 collimates the incident light from the projection lamp 9 to the polarization beam splitter 11, and the polarization beam splitter 11 allows the p-polarized component of the incident light to pass while the advancing direction of the s-polarized component. Is bent at a right angle.

As shown in FIG. 5, the writing LCD panel 23 is composed of a transmissive liquid crystal display (LCD), and has a black mask 41 and a large number of pixels 42. The drive of each pixel 42 is performed by an active drive element such as a TFT or by simple multiplex drive. As the writing LCD panel 23, TF is used.
T drive system is adopted. The pitch of each pixel 42 is X
The direction is pixel: black mask = 1: 2, and the Y direction is pixel: black mask = 1: 1.

In the above structure, the light emitted from the writing light source 1 shown in FIG. 1 enters the writing LCD panel 23 of the writing LCD panel device 3 through the collimator lens 2. At this time, the writing LCD panel 23
When an image is formed by the writing panel drive circuit 7, the image is written in the liquid crystal light valve 4 by the light from the writing light source 1.

In this case, in the liquid crystal light valve 4, when writing light enters from the glass substrate 31a side,
In the light-exposed region (bright state), the impedance of the photoconductor layer 33 decreases, and the voltage applied from the AC power supply 39 is applied to the liquid crystal layer 38. On the other hand, the impedance of the photoconductor layer 33 does not change and the voltage is not applied to the liquid crystal layer 38 in a region not exposed to light (dark state). An image is written in the liquid crystal layer 38 due to the difference between the bright state and the dark state.

On the other hand, the light emitted from the projection lamp 9 shown in FIG. 2 enters the polarization beam splitter 11. Of this incident light, the P-polarized component is the polarization beam splitter 1
1 and the S-polarized component is polarized beam splitter 11
Then, the traveling direction is bent at a right angle and enters the liquid crystal light valve 4. This incident light is reflected by the dielectric mirror 35 of the liquid crystal light valve 4. Of these, the reflected light that has passed through the portion where the alignment state of the liquid crystal layer 38 has changed due to image writing changes the polarization direction due to the electro-optical effect (P-polarized component), and therefore can pass through the polarization beam splitter 11. . Thereafter, this reflected light is magnified by the projection lens 12, whereby the image of the writing LCD panel 23 is projected on the screen 13 and the image is displayed.

Here, in the above image display operation,
The writing LCD panel 23 is moved in the X direction and Y direction by the panel moving device 24 driven by the panel moving device driving circuit 6.
It is driven so as to oscillate in the X direction or the X and Y directions. Next, an image writing operation to the liquid crystal light valve 4 while vibrating the writing LCD panel 23 will be described.

For example, as shown in FIG. 6A, when the image displayed on the writing LCD panel 23 is written on the liquid crystal light valve 4, the writing LCD panel 23 is in a stationary state and does not move. The light from 1 transmits through the writing LCD panel 23, and the liquid crystal light valve 4
Is written to.

Next, the writing LCD panel 23 is driven by the panel moving device 24 to move one pixel in the Y direction, for example, as shown in FIG. During this movement, the writing light source 1 is turned off by the operation of the light source driving circuit 5 in this embodiment, and writing to the liquid crystal light valve 4 is not performed.

Next, after the movement of the writing LCD panel 23 is completed, the writing light source 1 is turned on and the writing LC is turned on.
Writing to the liquid crystal light valve 4 is performed by the light transmitted through the D panel 23. At this time, the image displayed on the writing LCD panel 23 is an image displayed by an image signal matched to the moving position of the pixel. That is, this image is an image that cannot be displayed when the writing LCD panel 23 does not move, and the writing L
By the movement of the CD panel 23, that is, the vibration, the pixel is temporarily made to exist at the position where the pixel does not originally exist, so that the image can be displayed by the image signal corresponding to the position of the pixel.

By such an operation, the image writing to the liquid crystal light valve 4 is performed, and the synchronizing circuit 8 performs the light source driving circuit 5, the panel moving device driving circuit 6 and the writing so that the above-described operation is performed. The panel drive circuit 7 is synchronized.

As described above, in the present image display device, by sequentially repeating the movement of the writing LCD panel 23 and the writing to the liquid crystal light valve 4, the low resolution writing LC is performed.
Even with the D panel 23, high-resolution writing can be performed on the liquid crystal light valve 4. Here, the black mask 41 and the pixels 4 of the writing LCD panel 23 are used.
From the relationship of the pitch of 2, by moving 1 pixel to the left and right in the X direction and moving 1 pixel in the Y direction to write,
The resolution could be improved 6 times. Further, as compared with the conventional case, since the pixels are virtually present in the black mask portion, the aperture ratio can be improved and a bright display can be obtained. Further, since the liquid crystal light valve 4 has the afterimage property, there is no decrease in brightness on the reading light side even when performing time-division writing, and bright and high-resolution display can be realized.
Therefore, the image projected by the liquid crystal light valve 4 has a high resolution and a bright display with no reduction in brightness.

In this embodiment, the writing light source 1 is used.
The image writing to the liquid crystal light valve 4 is controlled by controlling the turning on / off of the.
It is also possible to perform the above writing control by controlling the CD panel 23 in the transparent state or the non-transparent state.

Further, the writing LCD panel 23 vibrates.
It is also possible to directly obtain a projected image from the above, that is, to omit the liquid crystal light valve 4 in the configuration shown in FIGS. This is the actual Kaihei 6-48285
It also corresponds to the configuration for directly obtaining a projected image from the vibrating image display element shown in No. However, in such a configuration, the vibration frequency of the writing LCD panel 23 (image display element) is set to a frequency (3) that does not cause flickering with human eyes.
0 Hz) or higher, and further, in order to increase the resolution, for example, to increase the resolution by a factor of 4, the vibration frequency needs to be quadrupled, that is, 120 Hz or higher. Further, in this case, since the image is displayed in a time-divisional manner in order to increase the resolution, the brightness of the image is 1/4 or less (when the resolution is quadrupled) as compared with the case where the resolution is not increased.
Therefore, there is an inconvenience that the display becomes dark.

On the other hand, when the image is once written in the liquid crystal light valve 4 and is projected and displayed as in the present embodiment, it is possible to obtain a state in which each pixel is constantly lit. Without reducing the brightness of the image
Higher resolution can be realized.

[Embodiment 2] Another embodiment of the present invention will be described below with reference to FIG. For convenience of explanation, the same reference numerals will be given to the means having the same functions as those shown in the above-mentioned embodiment, and the description thereof will be omitted.

The image display device of this embodiment is the same as that of the first embodiment.
Similar to the image display device, the light from the writing light source 1 is incident on the writing LCD panel device 3 through the collimator lens 2 and the image formed on the writing LCD panel device 3 is written in the liquid crystal light valve 4. Has become.
However, in this image display device, the writing LCD panel 23
Is not moved, but the writing light source 1 is moved in the Y direction. To this end, the image display device includes a light source moving device 51 and a light source moving device driving circuit 52.

The light source moving device 51 includes a stepping motor 53, a gear 54 provided on the rotating shaft of the stepping motor 53, a gear 55 meshing with the gear 54, and a rotation of the gear 55 in the Y direction. It is composed of a light source holder 56 having a structure for converting into one movement. In this image display device, by moving the writing light source 1,
Since the image forming position when the image displayed on the writing LCD panel 23 is written in the liquid crystal light valve 4 moves in the Y direction, the writing light source 1 should be shifted by one pixel when the image is formed.
If is moved, the resolution can be improved according to the same principle as the structure for moving the writing LCD panel 23 of the first embodiment.

In the operation in this case, the writing LCD panel 23 is operated with the movement of the writing light source 1 stopped.
Writing is performed in the liquid crystal light valve 4 by the light from the writing light source 1 that has passed through. Next, the writing light source 1 is moved in the Y direction by the operation of the light source moving device 51 driven by the light source moving device driving circuit 52, and the image forming position of the liquid crystal light valve 4 is shifted by one pixel. During this movement, the writing light source 1 is turned off, and the writing light source 1
After completing the movement of L, turn on the writing light source 1 and write L
The image displayed on the CD panel 23 is displayed on the liquid crystal light valve 4.
Write in. At this time, the image displayed on the writing LCD panel 23 is supplied with an image signal in accordance with the pixel moving position, as in the case of the first embodiment, so that a high-resolution image is formed on the liquid crystal light valve 4. Therefore, the synchronizing circuit 8 synchronizes the light source driving circuit 5, the light source moving device driving circuit 52, and the writing panel driving circuit 7.

As described above, by sequentially moving and writing the writing light source 1, a low-resolution writing LCD is obtained.
High-resolution writing can be performed on the panel 23, and the resolution can be improved. Further, as compared with the conventional case, since the pixels are virtually present in the black mask portion, the aperture ratio can be improved and a bright display can be obtained. In addition, since the photo-addressable light valve has an afterimage property, there is no decrease in brightness on the reading side even when performing time-division writing, and bright and high-resolution display can be realized.

In this embodiment also, the writing light source 1 is used.
Instead of the lighting control of, the transmissive state / non-transmissive state of the writing LCD panel 23 may be controlled.

[Embodiment 3] Still another embodiment of the present invention will be described below with reference to FIGS. 8 and 9. For convenience of explanation, the same reference numerals will be given to the means having the same functions as those shown in the above-mentioned embodiment, and the description thereof will be omitted.

In the image display device of this embodiment, as shown in FIG. 8, an electroluminescent panel (hereinafter referred to as an EL panel) having a light emitting property as an image writing means.
61 is used. The image formed on the EL panel 61 is written in the liquid crystal light valve 4 via the collimator lens 2. The EL panel 61 is provided in a writing EL panel device 62, and the writing EL panel device 62 moves the EL panel 61 in the X direction and the Y direction by a panel moving device 63 as moving means.

As shown in FIG. 9, the panel moving device 63 is provided with an outer frame 64, an inner frame 65 and panel moving portions 66 and 67. The inner frame 65 is provided in the outer frame 65 and is movable in the Y direction.
The EL panel 61 is provided in the inner frame 65 and is movable in the X direction.

The panel moving parts 66 and 67 utilize piezoelectric elements. The panel moving unit 66 is provided with the outer frame 64.
And a piezoelectric material 66a provided between the inner frame 65 and
And electrodes 66 provided on both sides of the piezoelectric material 66a
It consists of b.66c. The piezoelectric material 66a has an upper surface connected to the outer frame 64 and a lower surface connected to the inner frame 65. The panel moving unit 67 includes a piezoelectric material 67a provided between the inner frame 65 and the EL panel 61, and electrodes 67b and 67c provided on both sides of the piezoelectric material 67a.
Consists of In the figure, the left side surface of the piezoelectric material 67a is connected to the inner frame 65, and the right side surface thereof is connected to the EL panel 61.

The EL panel 61 is driven in the Y direction by the panel moving unit 66, and is driven in the X direction by the panel moving unit 67. That is, the electrodes 66b and 66 are attached to the piezoelectric material 66a.
When a voltage is applied through c, the piezoelectric material 66a is deformed by the piezoelectric effect. As a result, the inner frame 65 in contact with the piezoelectric material 66a receives a force and moves downward in the figure, so that the EL panel 61 moves downward. On the other hand, when the voltage applied to the electrodes 66b and 66c is set to zero, the piezoelectric material 66a returns to its original state, and the inner frame 65, that is, the EL panel 61 moves upward. As a result, the EL panel 61 can be moved in the Y direction, and the voltage applied to the electrodes 66b and 66c is turned on / off.
By doing so, the EL panel 61 can be vibrated in the Y direction. Similarly, the EL panel 61 can be vibrated in the X direction by turning ON / OFF the voltage applied to the electrodes 67b and 67c of the piezoelectric material 67a. Further, the vibrations in the X direction and the Y direction can be independently performed.

By vibrating the EL panel 61 as described above, the position of the pixel can be moved in the X and Y directions when the image displayed on the EL panel 61 is written in the liquid crystal light valve 4. Therefore, when writing,
The resolution can be improved by moving the EL panel 61 so that it is shifted by one pixel in the Y direction.

In this case, with the EL panel 61 stopped, the EL panel 61 is caused to emit light and writing is performed in the liquid crystal light valve 4. Next, the EL panel 61 is driven by the panel moving device 63 to move in the X or Y direction so that the writing position of the liquid crystal light valve 4 is displaced by one pixel. The EL panel 61 is turned off during the movement, and after the movement is completed, it is caused to emit light to write the displayed image in the liquid crystal light valve 4. At this time, the image displayed on the EL panel 61 is supplied with an image signal matched to the moving position of the pixel so as to form a high-resolution image on the liquid crystal light valve 4, as in the case of the first embodiment. Therefore, the synchronizing circuit 8 shown in FIG. 8 synchronizes the panel moving device driving circuit 68 and the writing panel driving circuit 7.

As described above, by sequentially repeating the movement and writing of the EL panel 61, it is possible to perform high-resolution writing in the EL panel 61 and improve the resolution. Further, as compared with the related art, since the pixels can be made to exist in the portions where there are no pixels, the aperture ratio can be improved and a bright display can be obtained. Also, the liquid crystal light valve 4
Has an afterimage property, so that even if time-division writing is performed, there is no decrease in brightness on the reading light side, and bright, high-resolution display can be realized. Further, since the EL panel 61 has the functions of an image writing element and a writing light source, the configuration of the image display device can be simplified.

In this embodiment, the EL panel 61 is moved by the panel moving device 63 using the piezoelectric element 65. Instead of the panel moving device 63, the panel moving device using an electromagnet is used. It is also possible to use 24. On the contrary, the panel moving device 63 can be used instead of the panel moving device 24.

[0061]

As described above, the image display device according to the first aspect of the present invention is a photo-addressable light including at least a photoconductor layer and a liquid crystal layer between a pair of translucent substrates having electrodes. An image writing means for writing an image in the optical address type light valve, which has a bulb, an image writing element in which pixels are arranged two-dimensionally, and a light emitting source for writing, and an optical address type light by the image writing means. An image corresponding to this position is written in the image writing position in the optical address type light valve that is moved by the movement unit that moves the image writing position in the bulb periodically by the movement of the image writing unit and the movement of the moving unit. As described above, an image signal supplying means for supplying an image signal to the image writing element and an optical signal by the image writing means after completion of each moving operation by the moving means. It is configured to have a write driving means for causing a write operation to address type light valve.

As a result, it is possible to realize high resolution of the image display device at low cost without using an expensive high resolution type image writing element. Further, by projecting and displaying the image written in the optical address type light valve, it is possible to easily display a large-sized and high-resolution image. Further, since a small image writing element can be used, the image display device can be downsized. Therefore, there is an effect that a high-resolution and small-sized image display device can be realized at low cost.

The image display device according to the invention of claim 2 is
In the image display device of the invention of claim 1, the photo-addressable light valve is configured to have an image holding function.

As a result, in addition to the effect of the first aspect of the invention, the resolution of the image display device can be reliably improved, and there is no decrease in brightness on the reading light side, and high brightness display can be obtained. Play.

According to the image display device of the invention of claim 3,
In the image display device according to the invention of claim 1 or 2, the moving means moves the writing light source.

Thus, in addition to the effect of the invention of claim 1 or 2, the structure of the moving means is simplified as compared with the structure in which the image writing element having a large amount of wiring with respect to another device is moved to increase the resolution. There is an effect that can be realized.

The image display apparatus according to the invention of claim 4 is
In the image display device according to any one of claims 1 to 3, the image writing means is composed of an electroluminescent element.

As a result, in addition to the effects of the first to third aspects of the invention, since the electroluminescent element also serves as an image writing element and a writing light emitting source, the number of parts is reduced and the structure of the image display device is simplified. There is an effect that can be realized.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of an image display device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram for projecting and displaying an image of a photo-addressable liquid crystal light valve in the image display device.

FIG. 3 is a schematic front view of the writing LCD panel device shown in FIG.

4 is a vertical cross-sectional view of the optically addressable liquid crystal light valve shown in FIG.

5 is a conceptual diagram of the writing LCD panel shown in FIG. 1. FIG.

FIG. 6A is an explanatory diagram of an image writing state before the writing LCD panel is moved, and FIG. 6B is an explanatory diagram of an image writing state after the writing LCD panel is moved.

FIG. 7 is a configuration diagram of a main part of an image display device according to another embodiment of the present invention.

FIG. 8 is a configuration diagram of a main part in an image display device of still another embodiment of the present invention.

9 is a schematic front view of the writing EL panel device shown in FIG. 8. FIG.

FIG. 10 is a configuration diagram of a conventional projection-type image display device.

11 is a cross-sectional view of a liquid crystal light valve included in the image display device shown in FIG.

[Explanation of symbols]

1 light source for writing (light emitting source for writing, image writing means) 3 LCD panel device for writing 4 optical address type liquid crystal light valve (optical address type light valve) 5 light source drive circuit (writing drive means) 6 panel moving device drive circuit 7 Writing panel drive circuit (image signal supplying means) 8 Synchronous circuit (writing drive means) 23 LCD panel for writing (image writing element, image writing means) 24 Panel moving device (moving means) 25 to 28 Panel moving section 51 Light source movement Device 52 Light source moving device driving circuit 61 EL panel (image writing means) 62 Writing EL panel device 63 Panel moving device (moving means) 68 Panel moving device driving circuit

Claims (4)

[Claims] 1. An optical address type light valve including at least a photoconductor layer and a liquid crystal layer between a pair of transparent substrates having electrodes, and an image writing element in which pixels are two-dimensionally arranged. , And an image writing means for writing an image in the optical address type light valve, and an image writing position in the optical address type light valve by the image writing means are periodically moved by moving the image writing means. An image signal for supplying an image signal to the image writing element so that an image corresponding to this position is written in the image writing position in the optical address type light valve moved by the moving unit to be moved and the operation of the moving unit. After completion of each moving operation by the supplying means and the moving means, the writing operation to the photo-addressable light valve by the image writing means is performed. An image display device characterized by comprising a writing drive means. 2. The image display device according to claim 1, wherein the optically addressable light valve has an image holding function. 3. The image display device according to claim 1, wherein the moving means moves the writing light emitting source. 4. The image display device according to claim 1, wherein the image writing means comprises an electroluminescent element.