JPH0744136A - Video display device - Google Patents

Abstract

PURPOSE:To obtain the inexpensive video display device which can display a high-definition image. CONSTITUTION:The video display device has plural recording and reproducing devices 1a-1d which record and reproduce an image generated by thinning out an original image by a specific method, a means 5 which synchronizes the recording and reproducing devices 1a-1d at least at frame and line levels when reproduced images are reproduced by the recording and reproducing devices 1a-1d, display devices 2a-2d which are provided corresponding to the recording and reproducing devices 1a-1d and display the reproduced images of the recording and reproducing devices 1a-1d, and an optical system which project the images of the display devices 2a-2d on a screen 6 and composes one image of them on the screen 6.

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 for displaying a high definition image.

[0002]

2. Description of the Related Art Conventionally, as a method of displaying an image, particularly a moving image, on a display device, there is a method of reproducing a video signal stored in a video tape recorder or a laser disk in a predetermined format and outputting it to the display device. An apparatus for storing and reproducing an HDTV signal having 1125 scanning lines and a signal band of 20 to 30 MHz has been put into practical use.

Such a high-definition video signal is displayed diagonally 100
If you display it on a large screen display device of inch or more, you can get realistic images.

As a large-screen display device, a projection display device is generally used in which an image displayed on a light valve is enlarged and projected by an optical system. A projection display device using a CRT or an active matrix type liquid crystal panel as a light valve has already been put to practical use.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
Considering the number of pixels, the resolution of V is 1920 × 1035, and the number of pixels of the 35 mm standard film is 3694.
It is still insufficient when compared with × 2676 (assuming that recording is performed with a spatial resolution of 175 lines / mm).

An apparatus for recording / reproducing an ultra-high-definition image exceeding HDTV handles a data rate of several Gb / s or more, and a head capable of recording / reproducing at an ultra-high density at an ultra-high speed, with high accuracy. There is a problem that an extremely expensive device such as a positioning mechanism and an ultra-high-speed signal processing circuit is used, and a recording time on a medium is shortened.

As for the display device, the CRT has a relationship in which the resolution and the brightness are in conflict with each other, and there is a problem that the brightness is lowered when the resolution is increased.

In a display device using a liquid crystal panel, it is necessary to reduce the pixel size by a microfabrication technique, but the liquid crystal panel becomes expensive due to a decrease in yield and the area occupied by an opening for transmitting light is reduced. The brightness decreases. Further, there is a problem that the circuit for driving the liquid crystal panel becomes high in speed and becomes an extremely expensive device.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a technology that enables an inexpensive video display device capable of displaying high-definition video. To do.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0011]

In order to achieve the above object, according to the present invention, a plurality of recording / reproducing devices for recording and reproducing an image obtained by thinning out an original image by a predetermined method, and the plurality of recording / reproducing devices. A means for synchronizing a plurality of recording / reproducing devices at least at a frame and line level when reproducing a reproduced image from the reproducing device, and the plurality of recording / reproducing devices provided corresponding to the plurality of recording / reproducing devices. It is characterized by having a plurality of display devices for displaying reproduced images of the device and an optical system for projecting the images of the plurality of display devices on a screen and synthesizing them into one image on the screen.

[0012]

According to the above means, the original image is thinned out by a predetermined method and recorded in a plurality of recording / reproducing devices, and the images are reproduced in synchronization with the plurality of recording / reproducing devices. Since it is displayed on the display device and combined into one image on the screen, a low resolution image is recorded in the recording / reproducing device, but a plurality of images are combined on the screen. Therefore, a resolution proportional to the number of recording / reproducing devices becomes possible, and an inexpensive video display device can be realized.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of a video display device which is an embodiment of the present invention.

This embodiment is an example in which four recording / reproducing devices and four projection type display devices provided corresponding thereto are used, and the recording / reproducing device is a laser disk device. The projection display device is a liquid crystal projection display device.

In FIG. 1, 1a to 1d are laser disk devices, 2a to 2d are projection type display devices provided corresponding to the laser disk devices 1a to 1d, 5 is a synchronizing signal generator, and 6 is a screen.

The sync signal generator 5 generates a vertical sync signal and a horizontal sync signal necessary for displaying a video signal,
The same signal is distributed to the laser disk devices 1a to 1d.

Since the laser disk devices 1a to 1d operate with the same synchronizing signal from the outside, the video signals reproduced and output from the four devices are frame and line (scanning line).
It is output in synchronization with the level.

The projection type display devices 2a to 2d provided corresponding to the laser disk devices 1a to 1d project the reproduced video signals from the corresponding laser disk devices 1a to 1d on the screen 6 in an enlarged manner.

An image obtained by thinning out an original image in advance by a predetermined method is recorded in each of the laser disk devices 1a to 1d.

FIG. 2 is a diagram showing an example of thinning out an original image of 2n × 2m pixels into four images.

In FIG. 2, the thinned image A is composed of odd columns and odd rows of the original image, the thinned image B is composed of even columns and odd rows of the original image, and the thinned image C is composed of odd columns of the original image. The thinned image D includes even rows and even rows of the original image.

The thinned images A to D are recorded in the laser disk devices 1a to 1d, respectively.

FIG. 3 is a diagram for explaining how reproduced video signals from the laser disk devices 1a to 1d are displayed on the liquid crystal projection display devices 2a to 2d.

To simplify the explanation, the number of pixels of the thinned image is 3 × 3 pixels.

FIG. 3A shows the shape of one pixel of the liquid crystal panel used for the light valve of the liquid crystal projection display device.

Each pixel has an opening for transmitting light and a shield for shielding light.

An image is formed in the opening portion, and the shield portion is for preventing light leakage from the wiring regions of the gate lines and the source lines for driving the pixels.

FIG. 3B illustrates a superposition projection method in which a plurality of such liquid crystal panels are used to superimpose the images of the respective liquid crystal panels between pixels to generate a high-definition image.

The thinned images A to D are displayed on the liquid crystal projection display devices 2a to 2d, respectively, and are displayed on the screen 6 so as to overlap each other as follows.

The thinned-out image B is displayed so that the opening portion shifted by half a pixel in the horizontal direction with respect to the thinned-out image A overlaps the shielding portion of the thinned-out image A.

The thinned image C is displayed in such a manner that the opening part shifted by half a pixel in the vertical direction with respect to the thinned image A overlaps the shielding part of the thinned image A.

The thinned-out image D is displayed such that the opening portion shifted by half a pixel in the horizontal direction with respect to the thinned-out image C overlaps the shielding portion of the thinned-out image C.

Since the thinned-out images A to D have the pixel relationship as described with reference to FIG. 2, the superimposed image has 6 × 6 pixels and becomes a four-fold high-definition image.

FIG. 4 is a block diagram showing a schematic configuration of a drive circuit of a liquid crystal panel used in the liquid crystal projection display device of the embodiment of FIG.

Since the liquid crystal panel drive circuits 3a to 3d have the same configuration in each of the liquid crystal projection display devices 2a to 2d, the liquid crystal projection display device 2a will be described here.

The reproduced video signal from the laser disk device 1a is amplified by the amplifier 10 so as to obtain the required contrast, and the gradation correction circuit 11 performs the voltage-transmittance characteristic of the liquid crystal or the inverse γ correction processing of the video signal. So that the gradation characteristic of the display on the screen becomes linear.

The polar inverting circuit 12 is necessary to drive the liquid crystal in an alternating current and outputs a polar positive video signal.

The timing circuit 14 receives the horizontal synchronizing signal (HD) and the vertical synchronizing signal (VD) from the laser disk devices 1a to 1d and generates various timing pulses for controlling the liquid crystal panel.

The SPV signal is a pulse that determines the display screen position in the vertical direction. The pulse is sequentially transferred by the clock CKV, and the gate driver scans the scanning line (gate line).
Are sequentially turned on.

The SPH signal is a pulse that determines the position of the display screen in the horizontal direction, is sequentially transferred by the clock CKH, samples the video signal from the polar inverting circuit 12, and the source driver drives the source line of the liquid crystal display unit 16. Then, this video signal is transferred.

Since the laser disk apparatuses A to D output video signals in synchronization with each other at the frame and line (scan line) levels by the sync signal generator 5, they are displayed on the liquid crystal panel of each liquid crystal projection display device. The frame position and scanning line position of the image are not displaced.

However, even if the scanning lines are synchronized at the scanning line level, as shown in FIG. 5, the horizontal synchronizing signals may be slightly shifted by Δt although the scanning line positions are the same.

FIG. 5 is a diagram showing a video signal of the laser disk devices A and B during one horizontal scanning period. In FIG. 5, t
A and tB indicate the time from the rising edge of the horizontal sync pulse at each video start position.

Since the timing circuit 10 is provided for each liquid crystal projection display device and receives the synchronization signal from the corresponding laser disk device, the SPH signal is set to a predetermined tA,
It can be individually adjusted to output at the position of tB.

Therefore, even if four images are superposed and displayed as shown in FIG. 3, the display pixels do not shift.

Although the laser disk device is used as a means for recording / reproducing an image, it is obvious that a video tape recorder or an image control device incorporating a frame memory may be used.

The video scanning system is not limited to the interlace system or the non-interlace system.

As described above, according to this embodiment,
The original image is thinned out by a predetermined method and recorded in a plurality of recording / reproducing devices, and the images are reproduced by synchronizing the plurality of recording / reproducing devices at the frame and line levels. The image is displayed on the display device, and then combined into one image on the screen.

As a result, a low-resolution image is recorded in the recording / reproducing apparatus, but since a plurality of images are combined on the screen, a high resolution proportional to the number of recording / reproducing apparatuses becomes possible. That is, high-definition video display devices can be realized at low cost because the high-definition of the number of units can be achieved by using ready-made recording / reproducing devices and display devices.

Further, when the liquid crystal projection display device is used as the display device, it is not necessary to make the pixels of the liquid crystal panel dense and operate at high speed, so that a high-definition image display device can be realized with an inexpensive display device. .

Although the present invention has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and it goes without saying that various modifications can be made without departing from the scope of the invention.

[0053]

As described above, according to the present invention,
The original image is thinned out by a predetermined method and recorded in a plurality of recording / reproducing devices, and the images are reproduced by synchronizing the plurality of recording / reproducing devices at the frame and line levels. The image is displayed on the display device, and then combined into one image on the screen.

As a result, a low-resolution image is recorded in the recording / reproducing apparatus, but since a plurality of images are combined on the screen, a high resolution proportional to the number of recording / reproducing apparatuses becomes possible. That is, high-definition video display devices can be realized at low cost because the high-definition of the number of units can be achieved by using ready-made recording / reproducing devices and display devices.

Further, when the liquid crystal projection display device is used as the display device, it is not necessary to make the pixels of the liquid crystal panel dense and operate at high speed, so that a high-definition image display device can be realized with an inexpensive display device. .

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a video display device according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of thinning an original image of 2n × 2m pixels into four images.

FIG. 3 is a diagram for explaining how to display a reproduced video signal from a laser disk device on a liquid crystal projection display device.

4 is a block diagram showing a schematic configuration of a drive circuit of a liquid crystal panel used in the liquid crystal projection display device of the embodiment of FIG.

5 is a diagram showing video signals of one horizontal scanning period of laser disk devices A and B. FIG.

[Explanation of symbols]

1a to 1d ... Laser disk device, 2a to 2d ... Projection display device, 3a to 3d ... Liquid crystal panel drive circuit, 5 ... Synchronous signal generation circuit, 10 ... Amplifier, 11 ... Gradation characteristic correction circuit, 12 ... Polarity inversion Circuit, 13 ... Source driver, 14
... Timing circuit, 15 ... Gate driver, 16 ... Liquid crystal display section.

Claims (1)

[Claims] 1. A plurality of recording / reproducing devices for recording and reproducing an image obtained by thinning out an original image by a predetermined method, and at least a frame and a line level when reproducing images reproduced from the plurality of recording / reproducing devices. Means for synchronizing a plurality of recording / reproducing devices with each other, a plurality of display devices provided corresponding to the plurality of recording / reproducing devices for displaying reproduced images of the plurality of recording / reproducing devices, and the plurality of display devices. An image display device, comprising: an optical system for projecting an image of the device onto a screen and synthesizing it into one image on the screen.