JPH07170470A - Liquid crystal display - Google Patents

Abstract

(57) [Abstract] [Purpose] To realize the picture-out-picture function by a conventional TV screen on a high-definition screen without using a large-scale digital processing circuit such as an image memory. [Structure] A liquid crystal display panel 25 having an aspect ratio of 9:16, and first and second signal electrode drive circuits 31 for dividing and driving the signal electrodes of the liquid crystal panel 25, respectively.
a to 31c, 32 and a first scan electrode drive circuit 33a to drive scan electrodes corresponding to the pixels of the liquid crystal display panel 25 on the side driven by the first signal electrode drive circuits 31a to 31c.
33c, and second scan electrode drive circuits 34a to 34c for driving scan electrodes corresponding to pixels on the side of the liquid crystal display panel 25 driven by the second signal electrode drive circuit 32.

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 for displaying an image on a screen having an aspect ratio different from that of the image by a picture-out-picture function.

[0002]

2. Description of the Related Art Recently, MUSE (Multiple Sub-Nyquist)
Aspect ratio of 9: 1 by Sampling Encoding method
Television devices having a high-definition screen of No. 6 have become widespread. FIG. 11 exemplifies this high-definition screen.

This high-definition screen has a conventional NTSC
When displaying a normal television image with an aspect ratio of 3: 4 according to the (National Television System Committee) method, normally, if it is desired to display the original image without missing, as shown in FIG. Is an unused area as indicated by hatching in the figure, and the image is displayed in the center of the screen.

As a method for effectively using the hatched area in FIG. 12, as shown in FIG.
On the other hand, a main screen (hereinafter referred to as "parent screen") is displayed on the left side, for example, and a small screen (hereinafter referred to as "child screen") is formed by using a part of the screen area on the right side, for example, the lower side. It is conceivable to use a so-called picture-out-picture function (hereinafter abbreviated as “PoutP function”) for displaying.

When the PoutP function is realized, the parent screen and the child screen are combined and displayed. However, since the sync signal and other signals are deviated between the parent screen and the child screen, in order to match them, for example, digital data of the child screen is temporarily stored in the memory, and the child screen is synchronized with the parent screen. The parent screen and the child screen are combined and output after being sequentially read from the memory and processed so that there is no time lag. Therefore, A is used for displaying the sub screen.
Digital processing circuits such as a D / D conversion circuit, a memory, a D / A conversion circuit, a timing signal generation circuit are required. Further, the parent screen also needs to be scanned earlier than in the normal display, and here also a digital processing circuit similar to the above for time axis compression is required.

[0006]

As described above, in order to realize the PoutP function by the conventional television image on the high-definition screen, the digital processing circuit is indispensable for both the parent screen and the child screen, and the entire circuit is indispensable. There was a problem that it was large and expensive.

The present invention has been made in view of the above situation, and an object thereof is to provide a picture on a conventional television screen on a high-definition screen without using a large-scale digital processing circuit such as an image memory. An object is to provide a liquid crystal display device capable of realizing an out-picture function.

[0008]

That is, the present invention provides 9:
A liquid crystal display panel having an aspect ratio of 16; first and second signal electrode driving circuits for driving the signal electrodes of the liquid crystal panel by dividing them into 3: 1; and the first signal of the liquid crystal display panel. It corresponds to a first scan electrode drive circuit that drives a scan electrode corresponding to a pixel driven by an electrode drive circuit, and a pixel driven by a second signal electrode drive circuit of the liquid crystal display panel. A second scan electrode drive circuit for driving the scan electrodes is provided.

[0009]

With the above structure, the signal electrode drive circuit and the scan electrode drive circuit for displaying the parent screen and the signal electrode drive circuit for displaying the child screen on one liquid crystal display panel. Since it is possible to operate the display and the scan electrode drive circuit asynchronously to execute display, the picture-out-picture function on a conventional TV screen can be performed on a high-definition screen without using a large-scale digital processing circuit such as an image memory. Can be realized.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a liquid crystal television device will be described below with reference to the drawings. FIG. 1 shows the entire circuit configuration. 11 is an antenna for receiving terrestrial waves, 12 is a BS antenna for receiving satellite broadcasting, and 13 is a video input terminal. The terrestrial television wave received by the terrestrial antenna 11 is sent to the first terrestrial tuner 14 and the second terrestrial tuner 15. The first terrestrial tuner 14 and the second terrestrial tuner 15 each select a designated channel from the received television waves, convert it into an intermediate frequency signal, and output the first IF circuit 16 and the second IF circuit. Send to 17.

The first IF circuit 16 and the second IF circuit
Reference numeral 17 denotes an intermediate frequency amplification circuit, a SAW filter, a video detection circuit, a video amplification circuit, an AFT detection circuit, etc., and an intermediate frequency signal from the first terrestrial tuner 14 and the second terrestrial tuner 15. Is amplified and video-detected, the obtained audio signal is output to an audio processing circuit (not shown), and the video signal is output to both the parent screen input changeover switch 18 and the child screen input changeover switch 19.

[0012] Further, for the satellite broadcast television signal received by the BS antenna 12, a designated channel is selected by the BS tuner 20, and thereafter, a video signal and an audio signal are extracted through various processes, and the audio signal is converted into an audio signal. The video signal is output to an audio processing circuit (not shown) and is also output to the parent screen input changeover switch 18 and the child screen input changeover switch 19.

A video signal is directly input to the parent screen input changeover switch 18 and the child screen input changeover switch 19 from an externally connected device via the video input terminal 13. An audio signal is input from an audio input terminal (not shown) together with a video signal input from the video input terminal and output to an audio signal circuit (not shown). The parent screen input changeover switch 18 and the child screen input changeover switch 19 are each controlled by the system controller 21 and are one of the first IF circuit 16, the second IF circuit 17, the BS tuner 20 and the video input terminal 13. The video signal is switched and selected and sent to the main screen chroma circuit 22 and the sub screen chroma circuit 23.

Parent screen chroma circuit 22 and child screen chroma circuit
Under the control of the system controller 21, the reference numeral 23 performs chroma processing on the video signals sent via the parent screen input changeover switch 18 and the small screen input changeover switch 19 to obtain a chroma signal, and the chroma signal is sent together. It is sent to the liquid crystal drive circuit 24.

The liquid crystal drive circuit 24 will be described in detail later, but is controlled under the control of the system controller 21 at 9:
The signal electrodes and scan electrodes of the LCD panel 25 having an aspect ratio of 16 are separately driven to display and output two screens, which are a parent screen and a child screen with a normal aspect ratio of 3: 4, or one high-definition screen. .

The system controller 21 controls the operations of the parent screen input selector switch 18, the subsidiary screen input selector switch 19, the BS tuner 20, the parent screen chroma circuit 22, the subsidiary screen chroma circuit 23 and the liquid crystal drive circuit 24. , The above LC
The screen is displayed in various forms by the D panel 25.

Next, detailed configurations of the liquid crystal drive circuit 24 and the LCD panel 25 will be described. FIG. 2 mainly shows a divided configuration of the liquid crystal drive circuit 24. Here, P
When the outP function is executed, as in the case of FIG. 13, the parent screen is displayed using the left 3/4 area of the LCD panel 25 having the aspect ratio of 9:16 as shown by the broken line in the drawing, and the remaining right third It is assumed that the child screen is displayed using the lower third of the area.

Therefore, the signal electrodes of the LCD panel 25 are equally divided into four, and the left three regions corresponding to the parent screen are divided into the first signal electrode drive circuits 31a to 31.
It is assumed that c drives the display and the second signal electrode drive circuit 32 drives the display of the remaining one area corresponding to the child screen.

Further, the scan electrodes in the display driven area of the first signal electrode drive circuits 31a to 31c of the LCD panel 25 are equally divided into three, and the first scan electrode drive circuits 33a to 33c sequentially scan and drive. Similarly, the scan electrodes in the display driven area of the second signal electrode drive circuit 32 are equally divided into three,
The scanning electrode driving circuits 34a to 34c are sequentially driven to scan.

FIG. 3 shows such electrode driving circuits 31a-31.
The driving connection state of the electrodes by c, 32, 33a to 33c and 34a to 34c is shown. As shown in the figure, the first signal electrode drive circuits 31a to 31c and the first scan electrode drive circuits 33a to 31c.
33c, the left 3/4 parent screen area of the LCD panel 25, and the remaining 1/3 of the right side driven by the second signal electrode drive circuit 32 and the second scan electrode drive circuits 34a to 34c.
It can be seen that the sub-screen area of 1 is completely divided and divided in the drive connection state of the electrodes although they are on the same panel.

In the circuit configuration as described above, when the LCD panel 25 is used to display a high-definition screen using the entire surface, as shown in FIG. The input is switched and selected, and only the chroma signal obtained by the parent screen chroma circuit 22 is supplied to the liquid crystal drive circuit 24 via the parent screen input changeover switch 18. Then, the first signal electrode drive circuits 31a to 31c, the second signal electrode drive circuit 32, and the first scan electrode drive circuit 33.
a-33c and the second scan electrode driving circuits 34a-34c are synchronized with each other to display one high-definition screen on the LCD.
Display using the entire surface of panel 25.

Further, as shown in FIG. 5, when the parent screen and the child screen are simultaneously displayed by the PoutP function on the LCD panel 25, the system controller 21 uses the parent screen input changeover switch 18 and the child screen input changeover switch 19 respectively. Select any input to switch it to the main screen input selector switch 18
The master screen chroma signal obtained by the master screen chroma circuit 22 via the sub screen and the sub screen chroma signal obtained by the sub screen chroma circuit 23 via the sub screen input selector switch 19 are supplied to the liquid crystal drive circuit 24. . Then, the first signal electrode drive circuits 31a to 31c
And the first scan electrode drive circuits 33a to 33c form a parent screen, and the second signal electrode drive circuit 32 and the second scan electrode drive circuit 34a.
~ 34c and the sub-screen, LCD panel 25 asynchronously
To display.

In the above embodiment, the configuration and the operation in the case of displaying the high-definition screen on the LCD panel 25 using the entire surface or displaying the parent screen and the child screen at the same time by the PoutP function have been exemplified. A case where more various screen displays are performed will be described below as another configuration example of the present invention.

That is, in another configuration example of the present invention, an LCD
The panel 25 is divided into four in the arrangement direction of the signal electrodes and three in the arrangement direction of the scanning electrodes to divide the whole into 12 block areas, and a signal electrode drive circuit and an operation electrode drive circuit are provided for each block area. By providing them independently, a maximum of 12 screens can be displayed.

FIG. 6 shows the division structure of the liquid crystal drive circuit 24 and the drive connection state of the electrodes corresponding thereto. The signal electrodes of the LCD panel 25 are equally divided into four, and one of them corresponds to the parent screen. The three regions on the left side are defined by the first signal electrode drive circuit groups 31a1 to 31a3, 31b1 to 31b3, 31c1 to 31.
It is assumed that c3 drives the display and the second signal electrode drive circuit groups 321 to 323 drive the remaining one area corresponding to the sub-screen.

Also, the first signal electrode drive circuit group 31a1 to 31a3, 31b1 to 31b3, 31c1 to 31 of the LCD panel 25.
The scan electrodes in the display-driven area of c3 are evenly divided into a total of nine block areas of vertical 3 × horizontal 3, and the first scan electrode drive circuit group 33a1 to 33a3, 33b1 to 33b3, 33c1 to.
It is assumed that each of 33c3 is sequentially scan driven.

On the other hand, the second signal electrode drive circuit group 321
The scan electrodes in the display-driven areas of the display devices ˜323 are equally divided into three block areas, and the second scan electrode drive circuit 34a
Up to 34c are sequentially scanned and driven.

For each such electrode drive circuit (group), the same input changeover switch as the parent screen input changeover switch 18, the small screen input changeover switch 19 and the like, and the corresponding parent screen chroma circuit 22, small screen A maximum of twelve chroma circuits similar to the chroma circuit 23 and the like are provided, and the system controller 21 controls the operation of these chroma circuits to enable screen display as shown in FIGS. 7 to 9.

FIG. 7 exemplifies a case where a high-definition screen is displayed by using the entire surface of the LCD panel 25. In this case, the system controller 21 switches and selects an arbitrary input by one input changeover switch, and supplies only the chroma signal obtained by the corresponding chroma circuit to the liquid crystal drive circuit 24 through the input changeover switch.

Then, the first signal electrode drive circuit group 31a1
.About.31a3, 31b1 to 31b3, 31c1 to 31c3 and second signal electrode drive circuit groups 321 to 323, first scan electrode drive circuit groups 33a1 to 33a3, 33b1 to 33b3, 33c1 to 33c3 and second scan electrode drive circuit. By synchronizing 34a to 34c with each other, one high-definition screen is displayed using the entire surface of the LCD panel 25.

FIG. 8 exemplifies a case where 12 block areas of the LCD panel 25 are used to display 12 screens. In this case, the system controller
The reference numeral 21 selects and selects any input from the 12 input changeover switches, and supplies the chroma signal obtained by the corresponding 12 chroma circuits to the liquid crystal drive circuit 24 via these input changeover switches.

The first signal electrode drive circuit 31a1 and the first scan electrode drive circuit 33a1, the same 31b1 and 33a2,
31c1 and 33a3, 31a2 and 33b1, 31b2 and 33b2
, 31c2 and 33b3, 31a3 and 33c1, 31b3 and 3
3c2, 31c3 and 33c3, second signal electrode drive circuit 321
And second scan electrode drive circuit 34a, 322 and 34b, 323
And 34c, 12 screens corresponding to 12 block areas are asynchronously displayed on the LCD panel 25.

Further, FIG. 9 shows that one of the 12 block areas of the LCD panel 25 is a total of 4 block areas of 2 × 2.
There are two that display one screen and four that display one screen in one block area, for a total of 6
This is an example of a case where individual screens are displayed. In this case, the system controller 21 switches and selects arbitrary inputs from the 6 input changeover switches out of 12, and the chroma signals obtained by the corresponding 6 chroma circuits via the input changeover switches are supplied to the liquid crystal drive circuit. Supply to 24.

Then, the first signal electrode drive circuit 31a1,
31b1, 31a2, 31b2 and the first scan electrode drive circuit 33a
1, 33a2, 33b1, 33b2, one signal electrode driving circuit 31c1, 31c2, second signal electrode driving circuit 321,
322 and the first scan electrode drive circuits 33a3 and 33b3, one second scan electrode drive circuit 34a and 34b, one signal electrode drive circuit 31a3 and the first scan electrode drive circuit 33c1 and 31b.
3 and 33c2, 31c3 and 33c3, the second signal electrode drive circuit 323 and the second scan electrode drive circuit 34c display one screen each and a total of six screens on the LCD panel 25 asynchronously for each screen.

When the display is performed on the screen of an arbitrary size using the arbitrary block area as described above, the first signal electrode drive circuit groups 31a1 to 31a3, 31b1 to 31b3, 31
In c1 to 31c3 and the second signal electrode drive circuit groups 321 to 323, the sampling timing of the chroma signal is controlled according to the size of the screen to obtain the drive signal according to the number of signal electrodes per screen. FIG. 10 exemplifies this sampling timing. For example, if FIG. 10 (1) shows an original chroma signal for a high-definition screen,
This is the entire surface of the LCD panel 25, that is, a total of 3 vertical x 4 horizontal
The sampling timing when displaying in two block areas is as shown in FIG. 10 (2) corresponding to the number of signal electrodes for four horizontal block areas.

Further, assuming that FIG. 10 (1) shows an original chroma signal for a normal TV screen having an aspect ratio of 3: 4, this is a total of nine blocks in the LCD panel 25, which are 3 × 3 in width. The sampling timing when displaying in the area is as shown in FIG. 10 (3) corresponding to the number of signal electrodes in the horizontal three block areas.

Further, the same original chroma signal for a normal TV screen as in the case of FIG.
The sampling timing when displaying in a total of 4 block areas of vertical 2 × horizontal 2 is as shown in FIG. 10 (4) corresponding to the number of signal electrodes for the horizontal 2 block areas.

Then, an original chroma signal for a normal television screen similar to the case of FIG. 10 (3) is supplied to the LCD panel 25.
The sampling timing when displaying in one block area in the inside is as shown in FIG. 10 (5) corresponding to the number of signal electrodes for one block area.

As described above, the smaller the number of signal electrodes corresponding to the number of signal electrodes corresponding to the screen, the more chroma signals are sampled at the thinned sampling timing.

In the above embodiment, the LCD panel 25 is divided into a total of 12 block areas of vertical 3 × horizontal 4 to enable screen display in each block unit.
By dividing into a total of 12n ² block regions of 4n in width (n is a natural number), it is possible to realize more various display patterns of a plurality of screens.

[0041]

As described above, according to the present invention, a signal electrode driving circuit and a scanning electrode driving circuit for displaying a parent screen on one liquid crystal display panel, and a child screen for displaying. Since the display can be executed by operating the signal electrode drive circuit and the scan electrode drive circuit asynchronously, a picture output by a conventional TV screen on a high-definition screen can be performed without using a large-scale digital processing circuit such as an image memory. It is possible to provide a liquid crystal display device that can realize a picture function.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall circuit configuration according to an embodiment of the present invention.

FIG. 2 is a diagram mainly showing a divided configuration of a liquid crystal drive circuit according to the embodiment.

FIG. 3 is a diagram showing a drive connection state to liquid crystal electrodes by each electrode drive circuit according to the embodiment.

FIG. 4 is a diagram exemplifying a display state of a screen according to the embodiment.

FIG. 5 is a diagram exemplifying a display state of a screen according to the embodiment.

FIG. 6 is a diagram showing a drive connection state to liquid crystal electrodes by each electrode drive circuit according to another configuration example of the embodiment.

FIG. 7 is a diagram exemplifying a display state of a screen according to another configuration example according to the embodiment.

FIG. 8 is a diagram exemplifying a display state of a screen according to another configuration example according to the embodiment.

FIG. 9 is a diagram exemplifying a display state of a screen according to another configuration example according to the embodiment.

FIG. 10 is a diagram showing a sampling timing of a chroma signal according to another configuration example according to the embodiment.

FIG. 11 is a diagram showing a general high-definition screen.

FIG. 12 is a diagram showing an example of displaying normal television screens having different aspect ratios on the high-definition screen of FIG. 11.

13 is a diagram exemplifying a case where two normal television screens having different aspect ratios are displayed on the high-definition screen of FIG. 11.

[Explanation of symbols]

11 ... Terrestrial antenna, 12 ... BS antenna, 13 ... Video input terminal, 14 ... First terrestrial tuner, 15 ... Second terrestrial tuner, 16 ... First IF circuit, 17 ... Second interface circuit , 18 ... Parent screen input selector switch, 19 ... Child screen input selector switch, 20 ... BS tuner, 21 ... System controller, 22 ... Parent screen chroma circuit, 23 ... Child screen chroma circuit, 24 ... Liquid crystal drive circuit, 25 ... LCD Panel, 31a-31
c, 31a1 to 31a3, 31b1 to 31b3, 31c1 to 31c3
... First signal electrode drive circuit, 32, 321 to 323 ... Second signal electrode drive circuit, 33a to 33c, 33a1 to 33a3, 33b1
.About.33b3, 33c1 to 33c3 ... First scan electrode driving circuit,
34a-34c ... 2nd scanning electrode drive circuit.

Claims (3)

[Claims] 1. A liquid crystal display panel having an aspect ratio of 9:16, first and second signal electrode drive circuits for dividing and driving the signal electrodes of the liquid crystal panel in a ratio of 3: 1, and the liquid crystal display. It is driven by a first scan electrode drive circuit that drives scan electrodes corresponding to pixels on the side of the panel that is driven by the first signal electrode drive circuit, and by the second signal electrode drive circuit of the liquid crystal display panel. And a second scan electrode drive circuit for driving the scan electrode corresponding to the pixel on the side of the liquid crystal display device. 2. A liquid crystal display panel having an aspect ratio of 9:16, a signal electrode of the liquid crystal panel is divided into 4n (n: natural number), and 3n continuous signal electrodes and n of the signal electrodes are divided.
First and second signal electrode driving circuits respectively driving the signal electrodes of the respective regions, and 3n scanning electrodes corresponding to pixels on the side driven by the first signal electrode driving circuit of the liquid crystal display panel. A first scan electrode drive circuit which is divided into 3 parts and is driven, and a scan electrode which corresponds to a pixel on the side driven by the second signal electrode drive circuit of the liquid crystal display panel is divided into 3n parts and driven. 2. A liquid crystal display device comprising: two scan electrode driving circuits. 3. A liquid crystal display panel having an aspect ratio of 9:16, and this liquid crystal panel is divided into 4n (n: natural number) in the arrangement direction of the signal electrodes and 3n in the arrangement direction of the scanning electrodes to form a whole. When divided into 12n ² block regions, a first signal electrode drive circuit group for driving the signal electrodes in each of the continuous 3n vertical × 3n horizontal block regions, and this first signal electrode drive circuit Vertical 3 left undriven by group
A second signal electrode drive circuit group that drives the signal electrodes in each of the n × horizontal n block regions, and a vertical 3n × horizontal 3n block region in which the first signal electrode drive circuit group drives the signal electrodes. And a second scan electrode drive circuit group that drives the scan electrodes, and a second scan electrode drive circuit group that drives the scan electrodes in the vertical 3n × horizontal n block regions in which the second signal electrode drive circuit group drives the signal electrodes A liquid crystal display device comprising a scan electrode drive circuit group.