JP2000221952A - Image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means for utilizing effectively the whole display region without lacking of the information of a present signal, when an image signal having a resolution lower than a resolution possessed by a display device itself is displayed. SOLUTION: This device has plural image input means and a means for synthesizing and displaying display images of plural image signals inputted from the plural image input means in invalid regions 3, 4 on a display screen, produced when main image signals having a lower resolution than a resolution possessed by a display device itself are displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dot matrix type image display device having a plurality of pixels and displaying an image by scanning a video signal in horizontal and vertical directions.

[0002]

2. Description of the Related Art Conventionally, a dot matrix type image display device has a horizontal and vertical shift register 1 as shown in FIG.
An image is displayed by sequentially writing video signals to pixels corresponding to intersections of signal lines and gate lines driven by the signal lines 4 and 15. That is, in the conventional example of the active matrix system shown in FIG. 3, first, when the first gate line g1 is selected by the vertical shift register 15, the pixel transistors M1, M2... Mn are turned on. Next, the horizontal shift register 14 scans the signal lines S1 and S1 sequentially.
S2... Sn are turned on and the pixel transistors M1, M2.
Through the pixel capacitors C1, C2,...
Charge to Cn. When the scanning on the gate line g1 is completed, the vertical shift register 15 selects the gate line g2 next and repeats the above-mentioned scanning sequentially.

[0003]

However, in the above-mentioned prior art, when a video signal having a resolution smaller than the total number of dots of the display device itself is to be displayed, the display area is reduced and a useless area is generated in the screen. Would. In addition, since the resolution of the input video signal is low, the amount of information obtained from the entire display screen is reduced. That is, according to the diagram for explaining the disadvantages of the conventional example shown in FIG.
For example, if VGA (640 horizontal dots, 480 vertical lines) video data is to be displayed on a display device capable of displaying XGA (1024 horizontal dots, 768 vertical lines), there is a shortage of data for 384 horizontal dots and 288 vertical lines. The hatched area becomes an invalid area.

[0005] A method of interpolating pixels, that is, as shown in the examples of FIGS.
By applying a video signal obtained by adding the respective average values between the signals corresponding to... To the display device, the display area can be enlarged 1.5 times in both the horizontal and vertical directions. Although the first problem is solved, the amount of information (VGA) obtained from the display screen itself does not change. Conventionally, as a method for increasing the amount of information obtained from a display screen, there is a picture-in-picture method implemented in a television receiver shown in FIG. 7, but according to this method, a part of a main first screen is used. Since the second and third screens are superimposed and displayed, there is a disadvantage that information on the first screen is partially missing.

[0005] Accordingly, an object of the present invention is to display an entire display area without losing information of a current signal when displaying a video signal having a resolution lower than that of the display device itself. It is to provide a means for effective use.

[0006]

In order to achieve the above object, the invention according to the present application has a plurality of video input means and displays a first video signal having a lower resolution than that of the display device itself. This is characterized in that display images of the second and third video signals are combined and displayed in an invalid area in the display screen generated when the display is performed.

[Operation] In the above configuration, the second and third image information are combined in the margin where the main first image of the entire display area is displayed, so that the main first image information is not lost in the display area. The entire surface can be used effectively.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of an image display device according to the present invention will be described in detail with reference to FIGS.

FIG. 1 is a diagram showing the configuration of a display screen according to the present invention. In FIG.
4 dots, 768 lines). The display screen is first displayed in the main display area 2 of the first video signal in this area.
2 displays a PC video signal having a VGA (640 dots, 480 lines) information amount. Next, the first margin 3 (384 horizontal dots,
The TV and VTR screens, which are the second and third video signals, are synthesized on 480 vertical lines). Further, a second margin 4 (horizontal 1) displaying the first, second, and third video signals is displayed.
(024 dots, 288 vertical lines) and a text broadcast which is the fourth video signal.

FIG. 2 is a diagram showing a circuit configuration for displaying the screen shown in FIG. In the figure, a plurality of first to fourth video input means 5 are prepared according to each video signal. Note that the number of video signals and video input means is not limited to four. The input video signal is separated into horizontal and vertical synchronizing signals HD and VD by the synchronizing separating means 6 and is separated by PL.
The signal is synchronously captured by the L circuit 7. The synchronously separated video signal is A / D converted by the A / D unit 9 at the timing generated by the timing generation circuit 8 and stored in the memory unit 10. At this time, the teletext signal, which is the fourth video signal, is character-combined by the character generation means 11 and then stored. The stored signals are read out from the memory means 10 by the horizontal / vertical writing position adjustment circuit 12 at the timing corresponding to the display position of each video signal, and sent to the display device 13.

That is, the PC video signal which is the first video in the horizontal direction is first read from the memory, and when the data for 640 dots is completed, the horizontal / vertical writing position adjustment circuit 12 next outputs the remaining 384 dots. Second to area
Alternatively, TV and VTR data, which is the third video signal, is read from the memory. Further, when the scanning for 480 lines in the vertical direction is completed, the horizontal / vertical writing position adjustment circuit 12 reads out the teletext data as the fourth video from the memory, thereby forming the display screen of FIG.

[0012]

As described above, according to the present invention,
A plurality of video input means, when displaying a main first video signal having a lower resolution than the resolution of the display device itself, a second portion in a margin portion for displaying the first video generated in the display screen; Since the screen of the third video signal is synthesized and displayed, it is possible to effectively utilize the entire display area without losing the first image information.

[Brief description of the drawings]

FIG. 1 is a diagram showing a display screen according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a circuit configuration according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a dot matrix type image display device.

FIG. 4 is a diagram showing a drawback of a conventional example.

FIG. 5 is a diagram illustrating one method of pixel interpolation.

FIG. 6 is a diagram showing an example of a display screen by pixel interpolation.

FIG. 7 is a diagram showing a display screen by picture-in-picture.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 All display area 2 Main 1st video signal display area 3 1st margin part 4 2nd margin part 5 Video input means 6 Synchronization separation means 7 PLL circuit 8 Timing generation circuit 9 A / D means 10 Memory means 11 Character generation means 12 Horizontal and vertical writing position adjustment circuit 13 Liquid crystal display device 14 Horizontal shift register 15 Vertical shift register

Claims (4)

[Claims] 1. A plurality of video input means, and input from the plurality of video input means to an invalid area in a display screen generated when displaying a main video signal having a lower resolution than the resolution of the display device itself. Means for combining and displaying display images of a plurality of video signals. 2. A plurality of video input means 5 prepared in accordance with each video signal, a synchronization separation means 6 for separating the input video signal into horizontal and vertical synchronization signals HD and VD, PLL circuit 7 for synchronizing and capturing, and A / D means for A / D converting the video signal desynchronized at the timing generated by timing generating circuit 8
9, a memory means 10 for storing the signal, and a signal stored in the memory means is read out from the memory means 10 at a timing corresponding to the display position of each video signal and sent to the display device 13 in horizontal and vertical writing. 2. The image display device according to claim 1, further comprising a position adjustment circuit. 3. The image display device according to claim 2, further comprising character generation means for synthesizing a character broadcast signal. 4. An image display device comprising a plurality of video input means, a synchronization separation means, a synchronization acquisition means, a timing generation means, an A / D means, a memory means, and a horizontal / vertical writing position adjusting means. And synthesizing a display screen of a plurality of other video signals in an invalid area in a display screen generated when displaying a main first video signal having a resolution lower than the resolution of the image display device itself. An image display device characterized by displaying.