JP2003295835A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make the display a high-quality moving picture performable by shortening the display time per one frame by using the conventional design method. <P>SOLUTION: In this liquid crystal display device, a period when active elements of scanning lines X<SB>1</SB>are made to be scanned in line sequential manner and a image data signal is written in the active elements and a period when the active elements of the scanning lines are made simultaneously active and arbitrary identical data signals are written in entire pixels, are provided in one frame and moreover, the scanning direction of the scanning lines is inverted into an opposite direction for every frame, in frames. <P>COPYRIGHT: (C)2004,JPO

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 used as an image display device such as a personal computer or a TV receiver.

[0002]

2. Description of the Related Art A conventional technique for an active matrix type liquid crystal display device will be described with reference to FIG. In this device, a plurality of scanning signal lines X1 to Xn and a plurality of data signal lines Y1 to Ym are arranged in a matrix. The scan driver 6 supplies a scan signal 10 to each of the scan signal lines X1 to Xn to drive them. The data driver 7 supplies the display data signal 11 to each of the data signal lines Y1 to Ym to drive them. The plurality of scanning signal lines X1 to Xn and the plurality of data signal lines Y1 to Ym are arranged on a panel which is a liquid crystal display unit in which a plurality of pixels are arranged in a matrix.

A transistor 1 that opens a gate in response to an input of a scanning signal 10 is provided at each of the intersections of these signal lines. Each of the gate electrodes of each transistor 1 is individually connected to the corresponding scanning signal line X1 to Xn. The source electrodes of each transistor 1 are individually connected to the corresponding data signal lines Y1 to Ym. Each drain electrode of each transistor 1 is individually connected to the pixel electrode 2 in the corresponding pixel. Further, a counter electrode 4 is arranged for display on the pixel electrode 2 with the liquid crystal 3 interposed therebetween. The counter electrode 4 of each pixel is connected from the counter electrode driver 8 to the counter bus line 5
It is driven by a common signal 12 which is commonly supplied via.

FIG. 3 is a circuit diagram of an arbitrary pixel. As shown in FIG. 3, the scanning signal line X has a scanning signal line resistance XR and a scanning signal line capacitance XC, and the data signal line Y has a data signal line resistance YR and a data signal line capacitance YC in parallel circuits. .

FIG. 4 is a diagram showing the timing at which the display data signal 11 is written in the pixel together with the scanning signal 10. FIGS. 4A to 4C show waveforms of scanning signals supplied from the scanning driver 6 to arbitrary scanning signal lines X _i-1 , X _i , and X _{i + 1} , respectively. FIG. 4D shows the waveform of the data signal supplied from the data driver 7 to the arbitrary data signal line Y _j . FIG. 4E shows the waveform of the common signal supplied from the counter electrode driver 8 to the counter electrode 4 of each pixel via the counter bus line 5. The data signals have a relation of opposite polarities with respect to the common signal between adjacent data signal lines. Figure 4
(F) shows the waveform of the pixel electrode 2-X _i Y _j in the pixel P _ij where the scanning signal line X _i and the data signal line Y _j intersect.

FIG. 4 (f) will be briefly described. 1 in FIG.
In H, the transistor 1-X _i Y _j corresponding to the pixel P _ij
A display data signal is supplied from the data signal line Y _j to the source electrode of. During this 1H, the gate electrode of the transistor 1-X _i Y _{j is connected to} the gate electrode of the transistor 1-X _i Y _j via the scanning signal line X _i in FIG.
Of active scan signals X _i are provided. As a result, the transistor 1-X _i Y _j corresponding to the pixel P _ij is turned on, and the liquid crystal 3-is connected to the pixel electrode 2-X _i Y _j connected to the drain electrode of the transistor 1-X _i Y _j. X _i
Data signals from the data signal line Y _j is written into Y _j.

[0007] After this 1H Since the scanning signal X _i supplied to the scanning signal line X _i becomes non-active, the pixel P
The voltage at the time when the transistor 1-X _i Y _j corresponding to _ij is turned off and the gate is turned off, that is, the data signal value from the data signal line Y _j is the pixel electrode 2-X _i Y _j.
It is a principle that is maintained.

Further, by supplying each data signal value in the opposite polarity centering on the common signal for each frame which is the display time of one image on the entire screen, the voltage applied to the liquid crystal becomes an alternating current. I have to.

The above is the outline of driving a general active matrix type liquid crystal display device.

[0010]

However, in such a conventional drive system of the active matrix type liquid crystal display device, the display data signal once written in the pixel electrode is delayed until the next transistor becomes active. It is accumulated between frames. Therefore, since the still image is continuously displayed over the one frame, the image remains in the eyes of the human, and when the moving image is displayed, it is perceived as an afterimage, and the image feels blurred. There's a problem.

The present invention solves the above-mentioned conventional problems and shortens the display time per frame in a high resolution active matrix type liquid crystal display device required for an LCD monitor or the like which is an alternative to a CRT. Accordingly, it is an object of the present invention to provide a drive system of an active matrix type liquid crystal display device which enables high quality moving image display.

[0012]

In an active matrix type liquid crystal display device of the present invention, a plurality of scanning signal lines for supplying scanning signals and a plurality of data signal lines for supplying data signals are respectively provided in image display. At the intersections of these signal lines, the scanning signal lines are connected to the drive terminal side electrodes of the three-terminal active element, and the data signal lines are connected to the one terminal side electrode of the active element, which are arranged in a matrix. A pixel electrode that constitutes a pixel is connected to the other-terminal-side electrode, and the pixel electrode has a structure in which a liquid crystal between the counter electrode and a storage capacitor are connected in parallel, and the common electrode is connected to the common electrode. To an active matrix drive type liquid crystal display device in which a signal is commonly supplied, and a common capacitance signal is supplied to the storage capacitor for each line parallel to the scanning signal line. The active elements of the scanning signal lines are activated line-sequentially during one frame, which is the time for displaying one image on the entire screen, and the active elements are activated all at once during the period for writing the image data signal. The above problem is solved by providing a period for writing an arbitrary same data signal in a pixel, and inverting the scanning direction of the scanning signal line in each frame in the opposite direction in the frame. There is.

Preferably, the respective image data signals are supplied to adjacent data signal lines with opposite polarities with respect to the common signal.

Further, according to the present invention, a plurality of scanning signal lines for respectively supplying scanning signals and a plurality of data signal lines for respectively supplying data signals are arranged in a matrix form, and at the intersections of the respective signal lines, The scanning signal line is connected to the drive terminal side electrode of the three-terminal active element, and the data signal line is connected to the one terminal side electrode of the active element.
A pixel electrode forming a pixel is connected to the other-terminal-side electrode of the active element, and a liquid crystal and a storage capacitor between the pixel electrode and the counter electrode are connected in parallel to the pixel electrode, and the counter electrode is connected to the counter electrode. A liquid crystal display device in which a common signal is commonly supplied, and a common capacitance signal is supplied to a storage capacitor for each line parallel to a scanning signal line.
During one frame, which is the display time of an image, the active elements of the scanning signal line are scanned line-sequentially to make them active, and during a period for writing an image data signal, all the active elements are made active at the same time, and all the pixels are made the same. A period for writing the data signal is provided, and in the frame,
The active matrix liquid crystal display device is characterized in that the scanning direction of the scanning signal line is reversed in the opposite direction for each frame.

Further, the present invention is a liquid crystal display device characterized in that each image data signal is supplied between adjacent data signal lines with opposite polarities centered on a common signal.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1) FIGS. 1A to 1E show the scanning driver 6 to scanning signal lines X _i-1 , X _i ,.
.., waveforms of scanning signals respectively supplied on X _{i + 3} are shown. FIG. 1F shows the waveform of the data signal supplied from the data driver 7 onto the data signal line Y _j . FIG. 1G shows the waveform of the common signal supplied from the counter electrode driver 8 to the counter electrode 4 of each pixel via the counter bus line 5. The data signal has a reverse polarity relationship with respect to the common signal between adjacent data signal lines, and has a reverse polarity relationship with the common signal as a center for each frame which is a display time of one image on the entire screen. . FIG. 1H shows the scanning signal line X _i and the data signal line Y _j.
7 shows the waveform of the pixel electrode 2-X _i Y _j in the pixel P _ij where the _points intersect.

FIG. 1 will be described in detail. One frame is divided into two (or more) subframes TH1 and TH2, the scanning signal lines are line-sequentially scanned at TH1 to supply the display data signal, and the scanning signal lines are simultaneously activated at TH2. The same data signal (for example, black state) is supplied to all pixels. Further, the scanning direction of the scanning signal line is reversed in every frame.

According to this method, the display time of image data per frame is shortened, the occurrence of the luminance gradient is made uniform over time, and high-quality moving image display is possible.

The above embodiment shows a basic structure, and it goes without saying that this structure may be modified as necessary.

[0021]

As described above, according to the present invention,
High-quality moving image display can be realized while using the conventional design method.

[Brief description of drawings]

FIG. 1 is a waveform diagram for explaining the operation of a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a general active matrix type liquid crystal display device.

FIG. 3 is a circuit diagram of an arbitrary pixel section of a general liquid crystal display device.

FIG. 4 is a waveform diagram for explaining the operation of a conventional liquid crystal display device.

[Explanation of symbols]

1 transistor 2 pixel electrodes 3 liquid crystal 3R liquid crystal resistance component 3C liquid crystal capacity component 4 Counter electrode 4R Counter electrode resistance 5 oncoming bus lines 6 Scan driver 7 Data driver 8 Counter electrode driver 9 Control circuit 10 scanning signals 11 Display data signal 12 common signal X1 to Xn scanning signal lines XR Scan signal line resistance XC scanning signal line capacitance Y1-Ym data signal lines YR data signal line resistance YC data signal line capacity

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) G09G 3/20 623 G09G 3/20 623U 660 660V F term (reference) 2H093 NA16 NA31 NA33 NA44 NA47 NB10 NB12 NB22 NB23 NC09 NC11 ND09 ND60 5C006 AA01 AA22 AC24 AC27 AF44 AF59 BB16 BC06 FA29 5C080 AA10 BB05 CC03 DD01 EE19 FF11 JJ03 JJ04 KK43

Claims (2)

[Claims] 1. A plurality of scanning signal lines for respectively supplying scanning signals and a plurality of data signal lines for respectively supplying data signals are arranged in a matrix, and the scanning signals are provided at intersections of the respective signal lines. A drive terminal side electrode of a three-terminal active element is connected to the line, and one terminal side electrode of the active element is connected to the data signal line, and a pixel is formed on the other terminal side electrode of the active element. A pixel electrode is connected to the pixel electrode, a liquid crystal between the pixel electrode and a counter electrode and a storage capacitor are connected in parallel, and a common signal is commonly supplied to the counter electrode. A liquid crystal display device in which a storage capacitor is supplied with a common capacitance signal for each line in a direction parallel to the scanning signal line, and the scanning signal is supplied during one frame which is a display time of one image on the entire screen. The active elements of the signal lines are activated by scanning them line-sequentially, and a period for writing the image data signal and a period for simultaneously activating the active elements and writing any same data signal in all pixels are provided, and In a frame, an active matrix type liquid crystal display device is characterized in that the scanning direction of the scanning signal line is reversed in every frame. 2. The liquid crystal display device according to claim 1, wherein the respective image data signals are supplied to adjacent data signal lines with opposite polarities with respect to the common signal.