KR100218525B1 - Driving method and circuit for display device of matrix type - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method and a driving circuit of a matrix type display device, and more particularly, to a driving method and a driving circuit for a mixture of two-line simultaneous scanning and point inversion. In the present invention, the polarity of the image signal is changed every two columns along the pixel column and the polarity of the image signal is changed every row or every three rows along the pixel column by using the two-line scanning method and the dot inversion method together. Flickering caused by the improved scanning method is prevented.

Description

Driving Method and Driving Circuit of Matrix Display

1 is a block diagram showing a driving circuit of a conventional matrix display device.

2A and 2B are timing diagrams of open / close signals used in a conventional method of driving a matrix display device, in which 2a is a timing diagram in an odd field and 2b is a timing diagram in an even field.

3A to 3E are diagrams showing, on a pixel-by-pixel basis, polarities of image signals shown in a conventional method of driving a matrix type display device.

4 is a sectional view showing a gate driving circuit according to the first embodiment of the present invention.

5 is a block diagram showing a data driving circuit according to a first embodiment of the present invention.

6A and 6B are timing charts of the open / close signal according to the first embodiment of the present invention, where 6a is a timing chart when an odd field and 6b are timing charts when an even field.

7A and 7B are timing diagrams of an open / close signal according to the first embodiment of the present invention, where 7a is a timing diagram of an image signal output from an upper data driving circuit and 7b is a timing diagram of an image signal output from a lower data driving circuit.

8A to 8D are diagrams showing, on a pixel-by-pixel basis, polarities of image signals shown in a method of driving a matrix display device according to the present invention.

9 is a circuit diagram showing a data driving circuit according to a second embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

11: shift register 10, 20: data driving circuit

12: pulse generator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method and a driving circuit of a matrix display device, and more particularly, to a driving method and a driving circuit for mixing a two-line simultaneous scanning method and a point inversion method.

Substituting the heavy, power-consuming conventional cathode ray tube (CRT), which is mainly used as a display device such as a computer monitor, liquid crystal display (LCD), plasma display There are various flat panel displays (FPD) such as plasma display panel (PDP), electroluminescence (EL), and field emission display (FED). Such flat panel displays employ a matrix wiring structure that is formed to be orthogonal to each other horizontally and vertically.

Liquid crystal displays are typical of portable matrix type flat panel displays, and among them, active matrix liquid crystal displays using thin film transistors as switching devices are mainly used. Amorphous silicon is mostly used as the thin film transistor, but a thin film transistor using polycrystalline silicon having high mobility and high integration has recently been in the spotlight.

Next, a driving method of the conventional polysilicon thin film transistor liquid crystal display device will be described in detail with reference to FIGS. 1 to 3.

First, a wiring structure and a driving circuit of a conventional polycrystalline silicon thin film transistor liquid crystal display will be described with reference to FIG. 1.

A plurality of data lines G1, G2, ..., Gm, Gm + 1, ... are formed horizontally and connected to the gate driving circuit, and a plurality of data lines D1, D2, ..., Dn, ... are formed and connected to the data driving circuit.

The method of applying data to each pixel in the liquid crystal display is as follows.

First, when an open / close signal is applied to the first gate line G1, the transistor of the pixel connected to the first gate line G1 is turned on, and the data lines D1, D2,..., Dn are turned on through the turned-on transistor. The image signal applied along ... is applied to the pixel.

Then, the open / close signal applied to the first gate line G1 is cut off, and the open / close signal is applied to the second gate line G2. Then, the transistor connected to the first gate line G1 is turned off and the second gate is turned off. The image signal is applied while the transistor connected to the line G2 is turned on. In this case, the applied signal is generally opposite in polarity to the data signal applied in the previous row.

In this manner, when the open / close signal is sequentially scanned to the last gate line, scanning starts again from the first gate line G1. At this time, it is common to apply the image signal of the next period opposite to the polarity in the previous period.

However, as the degree of integration increases, the number of data lines increases, and accordingly, a double scan method or a two line simultaneous scan method is newly used, unlike the conventional scanning method.

The double scan method increases the frequency of an image signal by doubling the frequency of the conventional signal, so that the cost is increased because separate image processing is required for the double scan, and the data sampling frequency of the data driver is increased. As a result, the time required for data to be written to one gate line is reduced, so that the image quality is hardly improved, and thus it is rarely used in the polycrystalline silicon thin film transistor liquid crystal display device.

The two-line simultaneous scanning method drives two gate lines at the same time. The two circuits are simultaneously driven by tying two gate lines such as the first, second, and third and fourth gate lines, thereby simplifying the driving circuit. There is a decreasing problem.

A conventional method for overcoming the problems of the two-improved simultaneous scanning scheme will be described with reference to FIGS. 2 and 3.

In this method, a scan frame corresponding to twice the scan period is divided into an odd field and an even field, and in the odd field, as shown in FIG. 2A, the first and second gate lines and the third field. • Scan at the same time with the fourth gate line and scan at the same time in the even field, as in FIG. 2B, scan with the first gate line, the second and third gate lines, and the fourth and fifth gate lines at the same time.

In this manner, since the image signals are continuously inverted and inputted, when the polarities of the image signals applied to each pixel matrix are viewed, when the polarity in the first frame odd field is equal to 3a, the polarity in the same frame even field is 3b. The polarity in the second frame odd field is 3c, the polarity in the even field is 3d, and the polarity in the third frame odd field is 3e.

In this case, however, the resolution in the vertical direction increases, but the polarity of the image signal of each gate line changes as the field changes. For example, when the polarities of the data lines input to the first column in FIGS. 3A to 3E are changed, they are changed to (+), (+), (-), (-), and (+). Accordingly, there is a problem in that image quality deteriorates due to the generation of 15 플리 flicker.

An object of the present invention is to solve this problem is to prevent the 15 ㎐ flicker phenomenon by mixing the dot inversion method with the two agitating scanning method.

The present invention for achieving the above object is a driving method of a matrix display device for performing a display operation according to a signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines,

Dividing a plurality of horizontal signal lines into a plurality of bundles including two or more horizontal signal lines and simultaneously applying an opening / closing signal to one horizontal signal line bundle,

Dividing the plurality of vertical signal lines into a plurality of bundles including one or more vertical signal lines, and applying image signals having different polarities to the adjacent vertical signal line bundles.

Here, the bundle of horizontal signal lines preferably includes two adjacent horizontal signal lines, and the bundle of vertical signal lines may consist of one or three adjacent vertical signal lines.

From here,

Applying an opening / closing signal to another horizontal signal line bundle,

The method may further include applying the image signal having the reversed polarity to the vertical signal line bundle.

In order to achieve the above object, the present invention also provides a method of driving a matrix display device that performs a display operation according to a signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines.

Dividing the plurality of horizontal signal lines into a plurality of bundles consisting of two horizontal signal lines adjacent to each other and sequentially applying an open / close signal to the horizontal signal line bundles,

The method includes dividing into bundles and applying image signals having different polarities to bundles of vertical signal lines adjacent to each other whenever an open / close signal is applied.

In this case, the vertical signal line bundle may consist of one vertical signal line, or the vertical signal lines in the vertical signal line bundle may be three vertical signal lines adjacent to each other.

Herein, whenever the horizontal signal line bundle to which the open / close signal is applied is changed, it is preferable to apply an image signal having a reversed polarity to the vertical signal line bundle, and the first field to which the open / close signal is applied once to all the horizontal signal line bundles is finished. Afterwards, it is divided into a plurality of bundles consisting of two horizontal signal lines neighboring each other, and divided into a bundle in the first field and another bundle to apply an open / close signal to the bundle of horizontal signal lines in turn, and the neighboring verticals each time the open / close signal is applied. The signal line bundle is preferably followed by a second field to which an image signal having a different polarity is applied.

In the preceding first and second fields, when one frame composed of the first and second fields is terminated without inverting the polarity of the image signal, the polarity of the image signal is inverted and applied to the vertical signal line bundle. It is good.

A driving circuit of a matrix display device for achieving this purpose includes a plurality of pixels arranged in a matrix form and performs display operation according to opening and closing signals and image signals applied through a plurality of horizontal signal lines and a plurality of vertical signal lines. A driving circuit of a matrix type display device, comprising: a first shift register for outputting an open / close signal to an odd horizontal signal line among horizontal signal lines and a second shift register for outputting an open / close signal to an even horizontal signal line among horizontal signal lines; An open / close signal driving circuit, a first image signal driving circuit for outputting an image signal to an odd-numbered vertical signal line among the vertical signal lines, and a second image signal driving circuit for outputting an image signal to an even-numbered vertical signal line among the vertical signal lines.

Another driving circuit of a matrix display device according to the present invention for achieving the above object includes a plurality of pixels arranged in a matrix form, the opening and closing signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines and A drive circuit for a matrix display device that performs a display operation in accordance with an image signal,

An open / close signal driving circuit comprising a first shift register for outputting an open / close signal to an odd-numbered horizontal signal line among the horizontal signal lines and a second shift register for outputting an open / close signal to an even-numbered horizontal signal line among the horizontal signal lines;

A first image signal driving circuit which outputs an image signal to an odd number of vertical signal line bundles by combining three adjacent vertical signal lines among one of the vertical signal lines, and a second image signal output to an even number of vertical signal line bundles among the vertical signal line bundles. Two image signal driving circuits.

Here, the first and second image signal driving circuits may include means for simultaneously applying a signal to a vertical signal line in one bundle of vertical signal lines, the signal applying means being a vertical signal line in accordance with a shift register and a signal therefrom. It may include a plurality of signal opening and closing means for opening and closing the image signal entering the.

The signal opening and closing means includes a pulse generator connected to a shift register and an output terminal connected to a vertical signal line, an image signal is applied to an input terminal, and two control terminals include a plurality of transmission gates connected to the pulse generator. do.

When the matrix display device is driven by the above method and apparatus, signals having reversed polarities are input along pixel rows and columns, thereby preventing flicker.

Next, a liquid crystal display according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings so that a person skilled in the art may easily implement the present invention.

4 is a block diagram showing a gate driving circuit according to a first embodiment of the present invention, in which the gate driving circuit includes two shift registers for driving odd and even gate lines separately. 1,2). The two shift registers 1 and 2 can simultaneously drive one of the odd-numbered gate lines and one of the even-numbered gate lines.

5 is a sectional view showing a data driving circuit according to a first exemplary embodiment of the present invention, in which an upper data driving circuit 10 formed on an upper part of a panel and a lower data driving circuit 20 formed on a lower part of a panel are shown. The data lines are alternately connected to the upper and lower data driving circuits 10 and 20.

Then, the timing of the open / close signal in the odd field shown in FIG. 6A, the timing of the open / close signal in the even field shown in FIG. 6B, and the image signal sent out from the upper data driving circuit shown in FIG. The driving method of the liquid crystal display device according to the present invention will be described in detail with reference to the timing diagram of and the timing diagram of the image signal emitted from the lower data driving circuit shown in FIG. 7B.

First, according to the simultaneous operation of two lines, in the odd field, two gate lines are grouped into one unit such as the first, second, and third and fourth gate lines as shown in FIG. In this case, as shown in FIG. 6B, the first gate line, the second and third gate lines, and the fourth and fifth gate lines are grouped into one unit to apply signals in sequence.

Next, when a bundle of gate lines is opened, the upper data driver circuit and the lower data driver circuit emit a signal of opposite polarity, and when the next bundle of gate lines is opened, the upper and lower data driver circuits reverse the polarity of the signal. send. For example, as shown in Figs. 7A and 7B, if an image signal of (+) polarity is applied from the upper data driving circuit when any one of the gate line bundles is opened, the lower data driving circuit is made of (-) polarity. When the signal is sent out and the next bundle of gate lines is opened, the upper data driving circuit, in contrast to the previous one, applies a negative polarity image signal from the upper data driving circuit, and the lower data driving circuit emits a positive polarity signal. .

This results in two polarities alternated along the rows, and two polarities reversed along the columns.

In the same frame, the polarity of the image signal is not inverted in accordance with the field. When the frame is changed, the polarity of the image signal is inverted. For example, if a positive polarity image signal is applied to an N th pixel row in a frame odd field, a positive polarity image signal is applied to an N th pixel row even in the even frame field. Is approved. However, in the odd field and the even field of the next frame, a negative polarity signal is applied to the N-th bundle of pixel rows.

8a to 8e show the polarity of the image signal in the first frame odd field, 8b shows the first frame even field, 8c shows the second frame odd field, 8d shows the third frame even field, and 8e shows the polarity of the image signal. Figure shows the polarity in the third frame even field.

As can be seen here, the polarities of the image signals appear alternately in the same field in two polarities along the rows and in the two columns along the columns. In the same frame, the same polarity is shown for pixel rows in the same order in odd and even fields. However, when the frames are changed, the polarities in the same order become opposite polarities.

In this way, the pixels of the adjacent pixel columns are applied with signals of inverted polarity, so that flicker is reduced.

Next, a method of driving the polycrystalline silicon thin film transistor liquid crystal display according to the second exemplary embodiment of the present invention will be described in detail with reference to FIG. 8.

The gate driving circuit according to the present embodiment is constituted in the same manner as in the first embodiment (see FIG. 4).

The data driving circuit according to the present embodiment has a slightly different structure from that in the first embodiment. That is, as shown in FIG. 8, the upper data driving circuit 10 formed on the upper part of the panel and the lower data driving circuit 20 formed on the lower part of the panel are respectively shift registers and a plurality of connected parts thereof. It includes a pulse generator and a plurality of transmission gates connected thereto.

In this embodiment, three data lines are bundled into one bundle, and the respective bundles are alternately connected to the upper and lower data driving circuits 10 and 20.

This is explained in more detail.

Each data line is connected to an output terminal of the transmission gates TG1, TG2, and TG3 to which a P MOS transistor and an N MOS transistor are coupled. Two control terminals of three transmission gates TG1, TG2, and TG3, which are respectively connected to three data lines in a bundle, are connected in parallel to one pulse generator 12.

In addition, the input terminals of the transmission gates TG1, TG2, and TG3 are connected to three signal lines R, G, and B for outputting image signals, respectively.

This embodiment adopting the above structure basically adopts the same driving method as the first embodiment, but unlike the first embodiment, it adopts a structure in which three data lines are bundled and output signals simultaneously. As a result, the time for applying the image signal is tripled as compared with the first embodiment.

To apply a signal to three data lines simultaneously, the pulse generator 12 generates an appropriate signal for opening and closing the transmission gates TG1, TG2, TG3 from the output of the shift register 11 and according to this signal, one pulse generator ( Three transmission gates (TG1, TG2, TG3) connected to 12) are simultaneously turned on or off, and the signals from the three signal lines (R, G, B) are respectively transmitted while the transmission gates (TG1, TG2, TG3) are turned on. Input is made with three data lines.

In this case, the three data lines are bundled in order to drive the three basic colors of red, green, and blue in one bundle.

The polarity shown by this embodiment is the same as that shown in FIGS. 8A to 8E. However, it should be noted that what is represented by one pixel in FIGS. 8A to 8E corresponds to three pixels in this embodiment.

As described above, in the matrix display device according to the present invention, by using a combination of the two-line simultaneous scanning method and the point inversion method, it is possible to prevent the generation of flicker that occurs in the conventional two-line simultaneous scanning method.

Claims (20)

A method of driving a matrix display device according to a signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines, the method comprising: dividing the plurality of horizontal signal lines into a plurality of bundles including two or more horizontal signal lines; Simultaneously applying an open / close signal to a bundle of horizontal signal lines, dividing the plurality of vertical signal lines into a plurality of bundles including one or more of the vertical signal lines, and applying image signals having different polarities to the adjacent bundles of vertical signal lines. A method of driving a matrix display device comprising a. The method of claim 1, wherein the horizontal signal line bundle comprises two horizontal signal lines. The method of claim 2, wherein the horizontal signal lines in the horizontal signal line bundle are adjacent to each other. The method of claim 1, wherein the vertical signal line bundle comprises one vertical signal line. The method of claim 1, wherein the vertical signal lines in the vertical signal line bundle are adjacent to each other. The method of claim 5, wherein the number of the vertical signal lines in the vertical signal line bundle is three. The driving method of claim 1, further comprising applying an opening / closing signal to the other horizontal signal line bundle, and applying an image signal having an inverted polarity to the vertical signal line bundle. A method of driving a matrix type display device according to a signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines, the method comprising dividing the plurality of horizontal signal lines into a plurality of bundles of two adjacent horizontal signal lines. Applying an opening / closing signal to the bundle of horizontal signal lines in turn, dividing the plurality of vertical signal lines into a plurality of bundles including one or more of the vertical signal lines, wherein each of the vertical signal line bundles adjacent to each other when the opening and closing signal is applied is polarized; A method of driving a matrix display device comprising the step of applying another image signal. The method of claim 8, wherein the vertical signal line bundle comprises one vertical signal line. The method of claim 8, wherein the vertical signal lines in the vertical signal line bundle are adjacent to each other. The method of claim 10, wherein the number of the vertical signal lines in the vertical signal line bundle is three. The driving method of claim 8, wherein an image signal having an inverted polarity is applied to the vertical signal line bundle whenever the horizontal signal line bundle to which the open / close signal is applied is changed. The method of claim 8, wherein after the first field to which the opening and closing path is applied to each of the horizontal signal line bundles is terminated, the bundle is divided into a plurality of bundles consisting of two adjacent horizontal signal lines. A matrix display device in which an open / close signal is sequentially applied to the horizontal signal line bundle and a second field for applying an image signal having a different polarity is applied to the adjacent bundle of vertical signal lines whenever the open / close signal is applied. Method of driving. The method of claim 13, wherein the polarity of the image signal is not inverted in the first field and the second field. 15. The method of claim 14, wherein when one frame consisting of the first field and the second field ends, the polarity of the image signal is inverted and applied to the vertical signal line bundle. A drive circuit of a matrix display device including a plurality of pixels arranged in a matrix form and performing display operation according to an open / close signal and an image signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines, wherein the horizontal signal lines An open / close signal drive circuit including a first shift register for outputting an open / close signal to the odd-numbered horizontal signal line and a second shift register for outputting an open / close signal to the even-numbered horizontal signal line among the horizontal signal lines, and the vertical signal line A first image signal driving circuit for outputting an image signal to the odd-numbered vertical signal lines, and a second image signal driving circuit for outputting an image signal to the even-numbered vertical signal lines of the vertical signal lines, wherein the odd-numbered horizontal signals are included. Open and close simultaneously with one of the signal lines and one of the even-numbered horizontal signal lines And a signal is applied, and image signals having different polarities are applied to adjacent vertical signal lines among the vertical signal lines. A drive circuit of a matrix display device including a plurality of pixels arranged in a matrix form and performing display operation according to an open / close signal and an image signal applied through a plurality of horizontal signal lines and a plurality of vertical signal lines, wherein the horizontal signal lines An open / close signal driving circuit including a first shift register for outputting an open / close signal to the odd-numbered horizontal signal line and a second shift register for outputting an open / close signal to the even-numbered horizontal signal line among the horizontal signal lines, and the vertical signal line A first image signal driving circuit for outputting an image signal to the odd-numbered vertical signal line bundle by using three adjacent vertical signal lines as one bundle, and an outputting of the image signal to the even-numbered vertical signal line bundle among the vertical signal line bundles; A second image signal driving circuit, said odd-numbered transverse scene An open / close signal is simultaneously applied to one of the lines and one of the even-numbered horizontal signal lines, and the odd-numbered vertical signal line bundle and the even-numbered vertical signal line bundle of the vertical signal lines are adjacent to each other, and the image signals of different polarities are provided. The driving circuit of the matrix display device to which is applied. 18. The driving circuit of claim 17, wherein the first and second image signal driving circuits comprise means for simultaneously applying a signal to the vertical signal lines in one bundle of the vertical signal lines. 19. The drive circuit according to claim 18, wherein the signal applying means includes a shift register and a plurality of signal opening and closing means for opening and closing the image signal entering the vertical signal line in accordance with a signal from the shift register. 20. The apparatus of claim 19, wherein the signal opening and closing means includes a pulse generator connected to the shift register, and an output terminal connected to the vertical signal line, and an image signal is applied to an input terminal. A driving circuit of a matrix display device including a plurality of transmission gates connected to each other.