JPH0627903A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To simplify a video signal processing circuit and to reduce its cost by displaying video signal different in an aspect ratio on the same liquid crystal panel. CONSTITUTION:The liquid crystal display device 10 consists of an aspect ratio A video signal processing circuit 11, an aspect ratio B video signal processing circuit 12, a signal generating circuit 13 for a residual area, a timing generating circuit 14, a video selecting circuit 15, a signal switching circuit 17, switch circuits 18a-18d, source driving circuits 20a-20d sectioned into four blocks, a gate driving circuit 21, a liquid crystal panel 30, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device,
In particular, the present invention relates to a liquid crystal display device capable of displaying video signals having different aspect ratios.

[0002]

2. Description of the Related Art When displaying a plurality of images on a screen of a display device at the same time, a so-called picture-in-picture system is used to insert a reduced sub-screen into a main screen or divide the screen into four screens. There is a method of performing multi-screen display by setting (9 division or 16 division is also possible).

The picture-in-picture system is
A large-capacity memory, a high-speed A / D converter, a D-A converter, and a controller for performing high-speed and complicated memory control are required, and the number of parts is large, and the circuit is technically sophisticated.

For example, on a horizontally long display screen having an aspect ratio of 9:16, a so-called high-definition HDTV
(High Definition Television) and other video signals with an aspect ratio of 9:16 and NTSC format video signals with an aspect ratio of 3: 4 can be displayed on a display device capable of displaying an image with an aspect ratio of 3: 4. There are two ways to do. One is, like the screen area shown in FIG.
In this method, the 9:16 video signal and the 3: 4 video signal have the same vertical screen size for display. The other is 9: 1 like the screen area shown in FIG.
This is a method of displaying the image signal of No. 6 and the image signal of 3: 4 with the same horizontal screen size.

In the display method of FIG. 3, the aspect ratio is 3: 4.
When displaying the video signal of, in order to secure the signal aspect ratio, the video signal of one horizontal line is 12/16 = 3.
It becomes possible to display by compressing the time to / 4 and using the signal of the undisplayed area for the remaining ¼ time.

In the display method of FIG. 4, the NTSC system has an aspect ratio of 3: so that the entire display area of the screen is displayed.
When displaying 4 video signals, in order to secure the aspect ratio of the signal, 9/12
Only the video signal of = 3/4 can be displayed.

[0007]

However, in the display method of FIG. 3, it is necessary to perform time compression of the video signal,
There is a problem that the video signal processing circuit becomes complicated and the manufacturing cost thereof becomes high. Further, the display method of FIG. 4 has a problem that a video signal of 1/4 in the vertical direction of the screen cannot be displayed on the screen and a part of the screen is not displayed.

In order to solve the above-mentioned problems, an object of the present invention is to enable video signals having different aspect ratios to be displayed on the same liquid crystal panel, and to simplify the video signal processing circuit and reduce the cost. An object of the present invention is to provide a liquid crystal display device that can be manufactured.

[0009]

According to the present invention, a plurality of picture element electrodes arranged in a matrix, a plurality of switching elements for controlling a voltage applied to the picture element electrodes, and a display signal to each switching element. A plurality of data lines for transmitting, and a plurality of scanning lines for transmitting a conduction signal of each switching element,
In a liquid crystal display device including a data line driving circuit that supplies the display signal to each data line and a scanning line driving circuit that supplies the conduction signal to each scanning line, the data line driving circuit divides a display screen. The liquid crystal display device is characterized by being divided into a plurality of blocks corresponding to regions.

The present invention further comprises a plurality of video signal processing means for processing a plurality of video signals having different display screen aspect ratios, and a video selection means for selecting a video signal to be displayed.
Based on the output of the remaining area signal generating means for displaying the remaining area excluding the display area of the video signal from the entire display screen and the output of the video selecting means, to the data line drive circuit divided into blocks. And a signal switching means for switching the input signal of.

According to the present invention, the data line driving circuit is 4
It is divided into two blocks and has an aspect ratio of 9: 1.
The first video signal of 6 is input to the data line driving circuit composed of four blocks, and the second video signal of aspect ratio 3: 4 is composed of three blocks out of four blocks. The data line driving circuit is inputted, and the signal from the remaining area signal generating means is inputted to the remaining one block of the data line driving circuit.

[0012]

According to the present invention, since the data line driving circuit is divided into a plurality of blocks corresponding to the divided areas of the display screen, a plurality of video signals having different aspect ratios of the display screen can be supplied to the same liquid crystal. It becomes possible to display it on the panel.

Further, a plurality of video signal processing means for processing a plurality of video signals having different display screen aspect ratios, a video selection means for selecting a video signal to be displayed, and a display area for the video signals from the entire display screen. And a signal switching means for switching the input signal to the data line driving circuit divided into blocks based on the output of the video selecting means. Thus, a desired screen display can be performed in the area excluding the display area of the video signal from the entire display screen.

The data line drive circuit is divided into four blocks, and the first aspect ratio is 9:16.
Image signal is input to a data line driving circuit including four blocks, and a second image signal having an aspect ratio of 3: 4 is input to a data line driving circuit including three blocks out of four blocks. By inputting the signal from the remaining area signal generating means to the remaining one block of data line driving circuit, the current HDTV or N
It is possible to display video without exhausting the video signal of the TSC system.

[0015]

1 is a block diagram showing a liquid crystal display device according to an embodiment of the present invention. An aspect ratio A video signal generating means 40 such as HDTV and an aspect ratio B video signal generating means 41 such as NTSC, which are so-called high-definition televisions, are external signal sources, and the liquid crystal display device 10 has an aspect ratio A video signal processing circuit. 11, aspect ratio B video signal processing circuit 12, remaining area signal generation circuit 13, video selection circuit 15, timing generation circuit 14, signal switching circuit 1
7, switch circuits 18a to 18d, source drive circuits 20a to 20d which are data line drive circuits, gate drive circuits 21 which are scan line drive circuits, and a liquid crystal panel 30 having an aspect ratio of 9:16.

The liquid crystal panel 30 has a plurality of picture element electrodes 31 arranged in a matrix, a plurality of switching elements 32 for controlling a voltage applied to the picture element electrodes 31, and a display signal to each switching element 32. Multiple data lines 34
And a plurality of scanning lines 33 for transmitting a conduction signal of each switching element 32, each pixel electrode 31 is a liquid crystal sandwiched between a counter electrode (not shown), and a display signal corresponding to a pixel. Is applied as a voltage.

In FIG. 1, when displaying an image of aspect ratio A such as HDTV, first, the image signal of aspect ratio A input from the aspect ratio A image signal generation means 40 is an aspect ratio A image signal processing circuit 11. Then, it is converted into a signal suitable for the liquid crystal panel 30, and the video selection circuit 1
By switching of No. 5, it is sent to the switch circuits 18a to 18d.

The video selection circuit 15 sends a control signal to the timing generation circuit 14 and the signal switching circuit 17 so that the video signal of the aspect ratio A is displayed.

The timing generation circuit 14 generates a timing signal suitable for the liquid crystal panel 30 based on the video signal having the aspect ratio A, and the source line drive circuits 20a to 20d.
Is input to the gate drive circuit 21.

In the signal switching circuit 17, the switch circuit 18a is arranged so that the signals from the aspect ratio A video signal processing circuit 11 are input to all the source drive circuits 20a to 20d.
Send a switching signal to ~ 18d. In this way, the video signal having the aspect ratio A is applied to and displayed on the entire display area of the liquid crystal panel 30.

Next, the aspect ratio B of the NTSC system, etc.
The case of displaying the video signal of will be described. As shown in Figure 2,
When a NTSC video signal with an aspect ratio of 3: 4 is displayed in the screen area of an aspect ratio of 9:16 such as an HDTV shown by a solid line with the same vertical screen size as shown by a broken line, a display image is displayed. The ratio of the horizontal length x of the display panel to the horizontal length y of the display panel is 12: 16 = 3: 4. From this, if the number of the source drive circuits 20a to 20d is four (or an integral multiple thereof), the NTSC signal is generated using three (or an integral multiple) of the source drive circuits 20a to 20d. By displaying, the aspect ratio is guaranteed.

In FIG. 1, the video signal input from the aspect ratio B video signal generating means 41 such as the NTSC system is converted into a signal suitable for the liquid crystal panel 30 by the aspect ratio B video signal processing circuit 12, and the video is selected. When the circuit 15 is switched, it is sent to the switch circuits 18a to 18d.

The video selection circuit 15 sends a control signal to the timing generation circuit 14 and the signal switching circuit 17 so that the video signal of the aspect ratio B is displayed.

The timing generation circuit 14 generates a timing signal suitable for the liquid crystal panel 30 based on the video signal having the aspect ratio B, and is input to the source drive circuits 20a to 20d and the gate drive circuit 21.

In the signal switching circuit 17, the source drive circuits 20a to 20b each composed of three blocks out of four blocks.
Input a video signal with aspect ratio B to 0c and leave 1
A switching signal is sent to the switch circuits 18a to 18d so that the video signal from the remaining area signal generation circuit 13 is input to the block source drive circuit 20d. The remaining area signal generation circuit 13 outputs a video signal for displaying white or black in a single color or for displaying character information, a clock, a so-called back program on another TV channel, etc. in synchronization with the video signal of the aspect ratio B. . A switching signal from the signal switching circuit 17 can determine whether to input the aspect ratio B video signal to any of the source drive circuits 20a to 20d. That is, when the video signal having the aspect ratio B is displayed on the liquid crystal panel 30, it is possible to set which of the source drive circuits 20a to 20d corresponding to the remaining display screen area.

In this embodiment, the source drive circuit 20
Although the example in which a to 20d are divided into four has been described, when the number of divisions is an integral multiple of 4 of 8 or more, more complicated screen division is performed by increasing the number of switch circuits 18a to 18d. It becomes possible to display.

[0027]

As described in detail above, according to the present invention,
Displaying video signals with different aspect ratios on the same liquid crystal panel by dividing the display area of the liquid crystal panel into blocks of the data line drive circuit without the need for complicated video signal processing circuits as in the past. Is possible.

Further, according to the present invention, it is possible to display an image divided into a plurality of areas at any place on the liquid crystal panel.

[Brief description of drawings]

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

FIG. 2 is a diagram showing a screen area of a liquid crystal display device according to an embodiment of the present invention.

FIG. 3 is a schematic diagram showing a method of displaying an image signal having an aspect ratio of 9:16 and an image signal having an aspect ratio of 3: 4 so that the vertical screen sizes are the same.

FIG. 4 is a schematic diagram showing a method of displaying a video signal having an aspect ratio of 9:16 and a video signal having a 3: 4 aspect ratio so that the horizontal screen size is the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Liquid crystal display device 11 Aspect ratio A video signal processing circuit 12 Aspect ratio B video signal processing circuit 13 Remaining area signal generation circuit 14 Timing generation circuit 15 Video selection circuit 17 Signal switching circuit 18a-18d Switch circuit 20a-20d Source drive circuit 21 gate drive circuit 30 liquid crystal panel 31 picture element electrode 32 switching element 33 scanning line 34 data line 40 aspect ratio A video signal generating means 41 aspect ratio B video signal generating means

Claims (3)

[Claims] 1. A plurality of picture element electrodes arranged in a matrix, a plurality of switching elements for controlling a voltage applied to the picture element electrodes, and a plurality of data lines for transmitting a display signal to each switching element, Liquid crystal including a plurality of scanning lines transmitting a conduction signal of each switching element, a data line driving circuit supplying the display signal to each data line, and a scanning line driving circuit supplying the conduction signal to each scanning line In the display device, the liquid crystal display device is characterized in that the data line driving circuit is divided into a plurality of blocks corresponding to divided areas of a display screen. 2. A plurality of video signal processing means for processing a plurality of video signals having different display screen aspect ratios, a video selection means for selecting a video signal to be displayed, and a display area for the video signals from the entire display screen. The remaining area signal generating means for displaying the remaining area except for, and the signal switching means for switching the input signal to the data line driving circuit divided for each block based on the output of the video selecting means. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is provided. 3. The data line drive circuit is divided into four blocks, and a first video signal having an aspect ratio of 9:16 is input to the data line drive circuit composed of four blocks, The second video signal having an aspect ratio of 3: 4 is input to the data line driving circuit composed of three blocks out of four blocks, and the remaining area signal is generated in the data line driving circuit of the remaining one block. The liquid crystal display device according to claim 2, wherein a signal from the means is input.