JPH09179091A - Image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the picture quality of right and left images and also make the picture quality high even unless the images are not viewed stereoscopically by using delta-array color liquid crystal panels for the image display device which uses two color liquid crystal panels. SOLUTION: This device has the two color liquid crystal panels and puts video lights obtained through the color liquid crystal panels one over the other to display an image. In this case, delta-array color liquid crystal panels are used and images which are one over the other on the screen are so displayed that pixels (circled) of one color liquid crystal panel shift by one pixel horizontally from pixels (indicated with squares) of the other color liquid crystal panel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device capable of color image display using a color liquid crystal panel.

[0002]

2. Description of the Related Art As a color image display device using a liquid crystal panel, there are dedicated liquid crystal panels for the three primary colors of R (red), G (green), and B (blue), and modulation is performed by each liquid crystal panel. A three-panel system in which the generated light is combined and projected on a screen with a single projection lens, or an R pixel portion, a G pixel portion, and a B pixel portion are repeatedly formed in order on one liquid crystal panel. There is known a single plate type using a color liquid crystal panel.

Further, two color liquid crystal panels each having an R pixel portion, a G pixel portion, and a B pixel portion repeatedly formed in order on one liquid crystal panel described above are used, and one of two field images forming one frame ( For example, an image display device is known in which an odd number side is displayed on a first color liquid crystal panel and the other (for example, even side) image is displayed on a second color liquid crystal panel.

In the image display device using the above-mentioned two color liquid crystal panels, each color liquid crystal panel having the stripe arrangement shown in FIG. 17 is used, and the superposition of images on the projection screen is As shown in FIG. 18, the position of the R pixel portion of the first color liquid crystal panel (each pixel portion thereof is circled) is the same as that of the second color liquid crystal panel (each pixel portion thereof is circled). (Denoted by) is shifted by 1.5 pixels from the position of the R pixel portion (that is, interleaved by 1.5 pixels), and the G of one color liquid crystal panel is horizontally aligned.
There is one in which the R pixel portion of the other color liquid crystal panel is located at an intermediate position between the pixel portion and the B pixel portion (see JP-A-6-078255: H04N 5/74).

As a result, the horizontal resolution can be improved as compared with the case where only one color liquid crystal panel having a stripe arrangement is used. For example, one color liquid crystal panel with a stripe arrangement has an H (horizontal) resolution of 160 TV.
In the case of a book and a V (vertical) resolution of 480 TV lines, the H resolution is 320 TV lines and a V resolution of 480 TV lines, and the horizontal resolution is improved.

[0006]

By the way, in the above-mentioned image display device using the first and second color liquid crystal panels, one of the two field images constituting one frame is used as the right-eye image, which is the first image. Displayed on a color liquid crystal panel, the other is displayed on the second color liquid crystal panel as an image for the left eye, and a shutter system using glasses that opens and closes left and right alternately for each field period, or P polarized light and S polarized light is used. It is conceivable to have the viewer perform stereoscopic vision by a polarization method using light.

Assuming that two color liquid crystal panels are used for three-dimensional display, each color liquid crystal panel is required to have a high horizontal resolution by itself. Therefore, it becomes necessary to use a color liquid crystal panel with a delta arrangement having a pixel arrangement as shown in FIG.

However, even if a color liquid crystal panel having a delta arrangement is used and interleaving for 1.5 pixels is performed as described above, the horizontal resolution cannot be improved as shown in FIG. Specifically, for example, when one color liquid crystal panel in the delta array theoretically has an H (horizontal) resolution 320 TV lines and a V (vertical) resolution 320 TV lines, an H resolution 320
TV lines and V resolution are 480 TV lines, and the horizontal resolution is not improved. Therefore, in an image display device using two color liquid crystal panels in the delta arrangement, the left and right images can be displayed with high image quality, but the image quality when stereoscopic viewing is not performed is similar to that of the stripe arrangement described above. It had a drawback that high image quality could not be expected.

In view of the above-mentioned circumstances, the present invention intends to improve the image quality of left and right images in an image display device using two color liquid crystal panels by using a color liquid crystal panel of the delta arrangement. At the same time, it is an object of the present invention to provide an image display device capable of achieving high image quality even when stereoscopic vision is not performed.

[0010]

In order to solve the above-mentioned problems, an image display device of the present invention has two color liquid crystal panels, and image light obtained through each color liquid crystal panel is displayed on a screen. In an image display device that is configured to perform image display by superimposing, a delta array type is used as the color liquid crystal panel, and the pixels of one color liquid crystal panel on the superimposed image on the screen It is arranged so as to be horizontally shifted by one pixel with respect to the pixels of the liquid crystal panel, and the video signal corresponding to each pixel of each color liquid crystal panel is sampled. And

According to the above arrangement, for example, a screen for image light by two color liquid crystal panels in which three color pixels of R (red), G (green) and B (blue) which form the three primary colors are arranged in a delta. Looking at the superimposed image above, the R pixel of the other color liquid crystal panel overlaps with the G pixel of one color liquid crystal panel at the same position, and only one G pixel row exists in the one color liquid crystal panel. The number of R pixel rows increases in the portion that has not been performed. Similarly, the G pixel row increases in the portion where only the B pixel row exists, and the B pixel row increases in the portion where only the R pixel row exists, so that the horizontal resolution can be improved.

The one color liquid crystal panel and the other color liquid crystal panel in which the pixel arrangements are horizontally offset from each other by one pixel may cause the one pixel shift. Alternatively, by shifting the relative positional relationship between one color liquid crystal panel and the other color liquid crystal panel having the same pixel arrangement configuration in the horizontal direction, the shift for one pixel is caused and each color liquid crystal panel is generated. In order to perform sampling of the video signal corresponding to each of the pixels, a delay circuit for delaying the video signal or the sampling timing given to the driving unit of any one of the color liquid crystal panels by a predetermined time may be provided. . Furthermore, the delay time of the delay circuit may be adjustable.

Further, a right-eye signal processing side for generating a right-eye image and supplying it to the one color liquid crystal panel, and a left-eye signal processing for generating a left-eye image and supplying it to the other color liquid crystal panel. A delay circuit may be provided to eliminate the shift in screen position due to the difference in the sync signal separation characteristics between the two sides. Further, the delay time of the delay circuit may be adjustable.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

The image display device of the present invention has two color liquid crystal panels, and the image light obtained through each color liquid crystal panel is superimposed on the screen to display an image. As the optical system part,
The structure shown in FIG. 2, FIG. 3, FIG. 4, or FIG.
Alternatively, other configurations can be used. The optical system shown in each drawing will be briefly described below.

The optical system shown in FIG. 1 is a two-light-source, two-projection-lens type optical system, in which the light emitted from the light source 1a is formed by a condenser lens 2a, which comprises a color filter 3a and a liquid crystal panel 4a. Guide to color LCD panel,
The image light obtained by the first color liquid crystal panel is projected onto the screen 6 by the first projection lens 5a, and the light emitted from the light source 1b is condensed by the condenser lens 2b and the color filter 3b and the liquid crystal panel 4b.
By guiding the image light obtained by the second color liquid crystal panel to the screen 6 by the second projection lens 5b.
The two images are superimposed and displayed on the screen 6.

The optical system shown in FIG. 2 is a two-light-source / one-projection-lens type optical system, in which the light emitted from the light source 1a is composed of a color filter 3a and a liquid crystal panel 4a by a condenser lens 2a. While being guided to the color liquid crystal panel, the light emitted from the light source 1b is guided to the second color liquid crystal panel composed of the color filter 3b and the liquid crystal panel 4b by the condenser lens 2b, and two images obtained by both color liquid crystal panels. The light beams are combined by the polarization beam splitter 7 and projected on the screen 6 through the projection lens 15 so that two images are displayed on the screen 6 in an overlapping manner.

The optical system shown in FIG. 3 is a one-light-source / one-projection-lens type optical system, in which light emitted from a light source 11 is split into two directions by a polarization beam splitter 8 to generate a first polarized light. By the condenser lens 2a and the reflection mirror 9a,
The second color liquid crystal including the color filter 3b and the liquid crystal panel 4b is guided to the first color liquid crystal panel including the color filter 3a and the liquid crystal panel 4a, and the second polarized light is generated by the condenser lens 2b and the reflection mirror 9b. Led to the panel, the two image lights obtained by both color liquid crystal panels are combined by the polarization beam splitter 7,
By projecting on the screen 6 via the projection lens 15, two images are displayed on the screen 6 in an overlapping manner.

The optical system shown in FIG. 4 is a one-light source, two-projection-lens type optical system in which a hologram color filter is used in place of the above-mentioned color filter.
The light radiated from 1 is split into two directions by the polarization beam splitter 8, and the first polarized light is condensed by the condenser lens 2a to the hologram color filter 13a and the liquid crystal panel 4.
and is guided to the first color liquid crystal panel consisting of a and a predetermined angle, and the image light obtained by this first color liquid crystal panel is projected on the screen 6 by the first projection lens 5a, and The polarized light is guided by the condenser lens 2b and the reflection mirror 19 to the second color liquid crystal panel composed of the hologram color filter 13b and the liquid crystal panel 4b with a predetermined inclination, and the image light obtained by the second color liquid crystal panel is guided. Is projected on the screen 6 by the second projection lens 5b, so that two images are superimposed and displayed on the screen 6.

The optical system shown in FIG. 5 is a projection lens type with one light source and uses a hologram color filter in place of the above-mentioned color filter.
The light emitted from the beam splitter 1 is split into two directions by the polarization beam splitter 8, and the first polarized light is reflected by the condenser lens 2a and the reflection mirror 9a.
3a and a liquid crystal panel 4a are guided to a first color liquid crystal panel at a predetermined angle, and the second polarized light is guided by a condenser lens 2b and a reflection mirror 9b to a second color liquid crystal panel 4b composed of a hologram color filter 13b and a liquid crystal panel 4b. The two image lights obtained by both color liquid crystal panels are guided to the color liquid crystal panel at a predetermined angle, are combined by the polarization beam splitter 7, and are projected on the screen 6 via the projection lens 15, whereby the screen 6 It is designed to display two images on top of each other.

In the optical system described above, the first color liquid crystal panel including the liquid crystal panel 4a and the color filter 3a (or the hologram color filter 13a), and the liquid crystal panel 4b and the color filter 3b (or the hologram color filter 13b). The second color liquid crystal panel consisting of and is both in the delta arrangement,
On the superimposed image on the screen 6, the pixels of the first color liquid crystal panel are displayed so as to be shifted by one pixel in the horizontal direction with respect to the pixels of the second color liquid crystal panel.

FIG. 6 is an explanatory view showing a superimposed image on the screen 6. As can be seen from this figure, the second color liquid crystal panel (each pixel portion is surrounded by □ is located at the same position as the G pixel of the first color liquid crystal panel (each pixel portion is represented by circle). R pixels of (shown) overlap each other (in this part, they are shown by superimposing ◯ and □), and in the part where only the G pixel row exists only in the first color liquid crystal panel. The number of R pixel columns will increase. Similarly, the G pixel row increases in the portion where only the B pixel row exists, and the B pixel row increases in the portion where only the R pixel row exists.

FIG. 7 is an explanatory diagram in which only the G pixel portion on the superimposed image of FIG. 6 is extracted and shown. As is clear from FIG. 7, the number of pixels which is twice as large as that of one color liquid crystal panel is shown. It can be seen that the columns are obtained. For example, one color LCD panel has H (horizontal) resolution 320 TV lines, V (vertical)
If the resolution is 320 TV lines, H resolution 640 TV
Book, the V resolution is 320 TV books, and the horizontal resolution is improved.

Here, as described above, the shift of one pixel in the two color liquid crystal panels on the screen 6 is such that the pixel arrangements are horizontally shifted from each other by one pixel in the first color shown in FIG. This can be realized by using the liquid crystal panel and the second color liquid crystal panel shown in FIG.

In the case where only one image light is reflected before reaching the screen 6 as in the optical system shown in FIG. 2, the first color liquid crystal panel shown in FIG. When the second color liquid crystal panel shown in FIG. 9 is used, the pixel array of one color liquid crystal panel cannot be used because the pixel arrangement is left and right. In such a case, for example, the color liquid crystal panel having the pixel arrangement shown in FIG. 16 may be used instead of the second color liquid crystal panel shown in FIG. When only one image light is reflected before reaching the screen 6 as in the optical system shown in FIG. 2, the scanning direction of the color liquid crystal panel which outputs one image light is used. Is reversed from the scanning direction of the other color liquid crystal panel.

On the other hand, it is also possible to use the two color liquid crystal panels having the same pixel arrangement configuration to generate the shift for one pixel. That is, as shown in FIG.
By shifting the relative positional relationship between the first color liquid crystal panel and the second color liquid crystal panel in the horizontal direction, a shift of one pixel can be generated. In this case, the video signal or sampling timing given to the drive unit of one of the color liquid crystal panels is delayed by a predetermined time so that the video signal corresponding to each pixel of each color liquid crystal panel is sampled. Will be required.

A circuit configuration for delaying a video signal or sampling timing given to the driving unit of any one of the color liquid crystal panels by a predetermined time will be described below with reference to FIGS.
5 will be described. In addition, in FIG. 11 to FIG. 13, a circuit configuration for generating a stereoscopic image is omitted.

FIG. 11A is a block diagram showing a circuit for delaying a video signal applied to the driving section of the color liquid crystal panel by a predetermined time. Video signal processing unit 51
Inputs an image signal, performs Y-C separation, color demodulation processing, level adjustment, etc., and outputs R (red) signal, G (green) signal, B
The (blue) signal is generated, and the R signal is the R video phase adjusting unit 5.
2, the G signal is supplied to the G video phase adjustment unit 53, and the B signal is supplied to the B video phase adjustment unit 54.

The video phase adjusting units 52, 53, 54 are provided with the first
R signal, G signal, B signal supplied to the driving unit 55a of the color liquid crystal panel 55 and R signal, G signal, B signal supplied to the driving unit 56a of the second color liquid crystal panel 56,
It is designed to give a phase difference. Specifically, looking at the video phase adjusting unit 52 for R, for example, the R1 signal supplied to the driving unit 55a of the first color liquid crystal panel 55 has a delay element as shown in FIG. The R signal is delayed for a predetermined time by 52a, and the R2 signal supplied to the driving unit 56a of the second color liquid crystal panel 56 is the R signal that is output as it is.

The control signal generator 57 receives the synchronizing signal separated from the video signal and generates a sampling timing (CLK) to be given to the drive section 55a and the drive section 56a. The same sampling timing is given to the drive unit 55a and the drive unit 56a.

As shown in FIG. 6C, the delay element 52a 'may be constructed so that the delay time can be adjusted by a delay amount control signal from the outside. As the delay elements 52a and 52a ', analog delay lines may be used or digital delay lines may be used.

FIG. 12A is a block diagram showing a circuit in which the sampling timing given to the driving section of the color liquid crystal panel is delayed by a predetermined time. The video signal processing unit 51 inputs a video signal, performs Y-C separation, color demodulation processing, level adjustment, and the like to perform R (red) signal and G signal.
A (green) signal and a B (blue) signal are generated, and these signals are first
To the driving section 55a of the color liquid crystal panel 55 and the driving section 56a of the second color liquid crystal panel 56. That is,
The drive unit 55a and the drive unit 56a are the same (no delay)
A video signal is given.

The control signal generator 57 receives the synchronizing signal separated from the video signal and generates a sampling timing (CLK). The sampling timing (CLK1) given to the driver 55a and the driver 5 are supplied.
The sampling timing (CLK2) given to 6a is different. Specifically, for example, the sampling timing (CLK2) supplied to the drive unit 56a is delayed by a delay element 58a for a predetermined time as shown in FIG. 7B, and the sampling timing (CLK1) supplied to the drive unit 55a. Is the same as CLK.

As shown in FIG. 6C, the delay element 58a 'may be constructed so that the delay time can be adjusted by a delay amount control signal from the outside. As the delay elements 58a and 58a ', analog delay lines may be used or digital delay lines may be used.

FIG. 13A is a block diagram showing a circuit in which the sampling timing given to the driving section of the color liquid crystal panel is delayed by a predetermined time. In the circuit of FIG. 13, the phase is shifted in the synchronizing signal which is the source of generating the sampling timing. Further, it has two video signal processing units 51a and 51b and two control signal generation units 57a and 57b.

The video signal processing units 51a and 51b respectively input the video signals, perform Y-C separation, color demodulation processing, level adjustment and the like to perform R (red) signals, G (green) signals and B signals.
A (blue) signal is generated, and these signals are supplied to the drive unit 55a of the first color liquid crystal panel 55 and the drive unit 56a of the second color liquid crystal panel 56, respectively. That is, the same video signal (without delay) is given to the drive unit 55a and the drive unit 56a.

The synchronizing signal phase adjusting section 59 inputs the synchronizing signal (SYNC) separated from the video signal, and outputs the synchronizing signal (SYNC1) to the control signal generating section 57a and the synchronizing signal (SYNC2) to the control signal generating section 57b. ) Is different from. Specifically, for example, the control signal generation unit 57.
The synchronizing signal (SYNC2) given to b is delayed by the delay element 59a for a predetermined time as shown in FIG.
Synchronous signal (SYNC1) given to the control signal generator 57a
Indicates that the synchronization signal (SYNC) is output as it is.

The control signal generators 57a and 57b are adapted to receive the different sync signals output from the sync signal phase adjuster 59 and generate sampling timing (CLK).

As shown in FIG. 6C, the delay element 59a 'may be constructed so that the delay time can be adjusted by a delay amount control signal from the outside. Also, as the delay elements 59a and 59a ', an analog delay line may be used or a digital delay line may be used.

FIG. 14 is a block diagram showing a circuit for delaying the sampling timing given to the driving section of the color liquid crystal panel by a predetermined time. The circuit of FIG. 14 includes a sync signal separation circuit 60a for the right-eye image and a sync signal separation circuit 60b for the left-eye image. By passing the output of the sync signal separation circuit 60b through the delay element 61, the sync signal provided to the control signal creation unit 57b is delayed by a predetermined time compared to the sync signal provided to the control signal creation unit 57a. Become.

If there is a difference in the sync signal separation characteristics between the sync signal separation circuit 60a and the sync signal separation circuit 60b,
The left and right screens are misaligned. Therefore, the delay element 61 causes a delay such that the video signal corresponding to each pixel of each color liquid crystal panel is sampled, and at the same time, a delay that eliminates the difference in the sync signal separation characteristics. It is supposed to cause. Further, the delay amount of the delay element 61 may be adjustable, and in this case, the delay amount can be adjusted according to the degree of the difference in the sync signal separation characteristics. The delay element 61 may be an analog delay line or a digital delay line.

FIG. 15 shows a sync signal separation circuit 60a for the right-eye image and a sync signal separation circuit 6 for the left-eye image.
0b is provided in common with that of FIG. 14, but in the circuit of FIG. 15, a delay element 61 is provided so as to delay the video signal supplied to the synchronization signal separation circuit 60b for a predetermined time. As a result, the control signal generator 57b
The sync signal given to the control signal generator 57a is delayed by a predetermined time compared with the sync signal given to the control signal generator 57a.

Also in this case, if there is a difference in the sync signal separation characteristics of the sync signal separation circuit 60a and the sync signal separation circuit 60b, a screen position shift occurs. Therefore, the delay element 61 causes a delay such that the video signal corresponding to each pixel of each color liquid crystal panel is sampled, and at the same time, a delay that eliminates the difference in the sync signal separation characteristics. However, in this case, the delay amount can be adjusted according to the degree of the difference in the sync signal separation characteristics.

[0044]

As described above, according to the present invention,
For example, when viewing a superimposed image of image light on a screen by two color liquid crystal panels in which three color pixels of R (red), G (green), and B (blue) that form three primary colors are arranged in a delta, The R pixel of the other color liquid crystal panel overlaps with the G pixel of the one color liquid crystal panel, and the R pixel column increases in the portion where only the G pixel column exists in the one color liquid crystal panel. It will be. Similarly, B
The G pixel row increases in the portion where only the pixel row exists, and the B pixel row increases in the portion where only the R pixel row exists, which brings about an effect of improving the horizontal resolution.

[Brief description of the drawings]

FIG. 1 is a layout view of optical components of an optical system used in an image display device of the present invention.

FIG. 2 is a layout view of optical components of an optical system used in the image display device of the present invention.

FIG. 3 is a layout view of optical components of an optical system used in the image display device of the present invention.

FIG. 4 is a layout view of optical components of an optical system used in the image display device of the present invention.

FIG. 5 is a layout view of optical components of an optical system used in the image display device of the present invention.

FIG. 6 is an explanatory diagram showing a pixel arrangement relationship on a screen by two color liquid crystal panels of the present invention.

FIG. 7 is an explanatory diagram showing a G pixel portion extracted from FIG. 6;

FIG. 8 is an explanatory diagram showing a pixel arrangement configuration of one color liquid crystal panel of the present invention.

FIG. 9 is an explanatory diagram showing a pixel arrangement configuration of the other color liquid crystal panel of the present invention.

FIG. 10 is an explanatory diagram showing sampling points of a video signal of the present invention.

FIG. 11 is a block diagram showing a circuit configuration for supplying a video signal to the color liquid crystal panel of the present invention.

FIG. 12 is a block diagram showing a circuit configuration for supplying a video signal to the color liquid crystal panel of the present invention.

FIG. 13 is a block diagram showing a circuit configuration for supplying a video signal to the color liquid crystal panel of the present invention.

FIG. 14 is a block diagram showing a circuit configuration for supplying a video signal to the color liquid crystal panel of the present invention.

FIG. 15 is a block diagram showing a circuit configuration for supplying a video signal to the color liquid crystal panel of the present invention.

16 is an explanatory diagram showing a pixel arrangement configuration of a color liquid crystal panel used in place of the other color liquid crystal panel of FIG. 9 when using the optical system of FIG. 2 of the present invention.

FIG. 17 is an explanatory diagram showing a pixel arrangement configuration of a stripe arrangement.

FIG. 18 is an explanatory diagram showing a pixel arrangement configuration when two projected color liquid crystal panels having a stripe arrangement are shifted by 1.5 pixels and respective projection lights are superimposed and displayed on a screen.

FIG. 19 is an explanatory diagram showing a pixel arrangement configuration of a delta arrangement.

FIG. 20 is a diagram showing two delta-aligned color liquid crystal panels 1.
It is explanatory drawing which shows a pixel arrangement structure when each projection light is superimposed and displayed on a screen by shifting 5 pixels.

[Explanation of symbols]

 1a, 1b Light source 3a, 3b Color filter 4a, 4b Liquid crystal panel 6 Screen 7 Polarizing beam splitter 8 Polarizing beam splitter 13a, 13b Hologram color filter

Claims (6)

[Claims] 1. An image display device comprising two color liquid crystal panels, wherein image light obtained through the respective color liquid crystal panels is superimposed on a screen to display an image. An array of pixels is used so that the pixels of one color liquid crystal panel are horizontally shifted by one pixel with respect to the pixels of the other color liquid crystal panel on the superimposed image on the screen. An image display device, characterized in that the image signal is sampled corresponding to each pixel of each color liquid crystal panel. 2. The one-pixel color liquid crystal panel and the other color liquid crystal panel, which are in a relationship in which the pixel arrangements are horizontally displaced from each other by one pixel, cause the one-pixel deviation. The image display device according to claim 1. 3. The one pixel liquid crystal panel and the other color liquid crystal panel, which have the same pixel arrangement configuration, are displaced in the horizontal direction in the relative positional relationship, thereby causing the one pixel shift and To sample the video signal corresponding to each pixel of the color liquid crystal panel,
The image display device according to claim 1, further comprising a delay circuit that delays a video signal or a sampling timing given to a driving unit of any one of the color liquid crystal panels by a predetermined time. 4. The image display device according to claim 3, wherein the delay time of the delay circuit is adjustable. 5. A right-eye signal processing side that generates a right-eye image and supplies it to the one color liquid crystal panel, and a left-eye signal processing that generates a left-eye image and supplies it to the other color liquid crystal panel. 5. The image display device according to claim 1, further comprising a delay circuit for eliminating a screen position shift due to a difference in mutual sync signal separation characteristic between the image display device and the image display device. . 6. The image display device according to claim 5, wherein the delay time of the delay circuit is adjustable.