KR100537885B1 - LCD and its driving method - Google Patents

Abstract

The liquid crystal display according to the present invention receives an image signal from a data driving circuit and an data driving circuit having odd-numbered output terminals and even-numbered output terminals respectively outputting inverted image signals, in pixel columns of a plurality of pixels in a matrix form. It consists of a liquid crystal panel having a data line for transmitting an image signal. At this time, among the wirings connecting the data line and the output terminal, the (3k + 1) th wiring and the (3k + 2) th wiring are staggered from each other. Accordingly, one pixel group consisting of three consecutive pixels among the rows of each pixel is connected to an output terminal of an odd column, and another pixel group consisting of three pixels adjacent to the pixel group is connected to an output terminal of the even column. have. Therefore, the (n-1) th pixel P is-, +, +, +,-,-,-,... … Polarities such as +, +, +,-, and-are displayed, and the nth pixel P has +,-,-,-, +, +, +,... … By displaying polarities such as-,-,-, +, and +, the pixel group consisting of three pixels is inverted like one pixel.

Description

LCD and its driving method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device and a driving method thereof, and more particularly, to a liquid crystal display device and a driving method thereof for inverting and driving a pixel group of red, green, and blue in units.

In general, the liquid crystal display is composed of a set of unit pixels performing a display operation as shown in FIG. 1, and each unit pixel is a signal (Vg, Vd) applied through the gate line (G) and the data line (D). Driven by. When the scan signal Vg is applied and the thin film transistor TFT is turned on, the data signal Vd is applied as the pixel voltage Vp to the pixel electrode through the thin film transistor TFT so that the common voltage Vcom is one side. It is stored in the liquid crystal capacitor Ccl serving as a terminal. Next, when the thin film transistor TFT is turned off, the signal stored in the liquid crystal capacitor Ccl is maintained through the storage capacitor Cst until the next data signal Vd is applied.

At this time, if the direct current voltage is continuously applied through the data line D due to the characteristics of the liquid crystal material, the liquid crystal material deteriorates and deteriorates the image quality.

In order to prevent this, the data signal is driven at a positive / negative voltage at regular intervals, and frame inversion, line inversion, and dot inversion are mainly used in the proposed method.

Among these, the frame inversion and the line inversion method have a serious problem such as crosstalk and flickering as the data line increases as the resolution of the screen becomes larger. It's a universal way.

Then, a general dot inversion driving method will be described in more detail.

2 is a block diagram illustrating a data driving integrated circuit and a pixel array of a dot inversion driving method according to the related art.

As shown in Fig. 2, the general dot inversion driving method first outputs the inverted signal of the positive / negative part to the signal line through the output terminal of the data driving integrated circuit 1, thereby red (R), green (G), and blue (B). A signal inverted in the order of positive / negative is applied to the (n-1) th pixel p columns arranged in an ordered sequence. Subsequently, the inverted signal neighboring the output terminal is output through the switching in the data driving integrated circuit 1, and the inverted signal is applied to the n-th pixel column in a negative / positive order.

In this way, an inverted signal is input to a neighboring pixel with respect to one pixel.

However, in the case of applying the dot inversion scheme, when a short occurs between adjacent pixels, the white state always appears in the two pixels, and thus it is recognized as a pixel defect. In addition, when the exposure process is performed by dividing the blocks into blocks in the manufacturing process and a difference in the coupling capacitance generated between the pixel electrode and the data line occurs due to the difference in alignment, the blocks may be different in units of blocks even if the same gray level is displayed. There is a problem that a so-called stitch defect occurs in which brightness is displayed.

In order to solve this problem, Korean Patent Application No. 97-49956 proposes a method of inverting a group of pixels adjacent to each other, in particular, a group of pixels consisting of three pixels of red, green, and blue.

An object of the present invention is to provide a method for inverting a pixel group composed of red, green, and blue pixels using a dot inversion driving integrated circuit.

In order to achieve the above object, a liquid crystal display according to the present invention receives an image signal from a data driving circuit and a data driving circuit having odd-numbered output and even-numbered output terminals respectively outputting inverted image signals. A liquid crystal panel having a data line for transmitting an image signal in pixel row units among pixels of a pixel, wherein a first pixel group including n pixels in a row of pixels is connected to an output terminal of the odd column; A second pixel group consisting of n pixels adjacent to the group is connected to the output terminals of the even columns.

In this case, the first and second pixel groups include three pixels of red, green, and blue, and two of the three signal lines connecting the data line connected to the three pixel rows and the output terminal for outputting the image signal to the data line. Are staggered with each other.

In the liquid crystal display according to the present invention, the pixel groups of red, green, and blue are inverted in units.

Next, exemplary embodiments of the liquid crystal display and the driving method thereof according to the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains can easily practice the present invention.

3 and 4 are diagrams illustrating pixel arrangements of a red, green, and blue inverted data driving integrated circuit and a liquid crystal panel according to an exemplary embodiment of the present invention, and FIG. 4 is a diagram illustrating an inversion of FIG. 3. .

First, as shown in FIGS. 3 and 4, the liquid crystal display according to the present invention includes a liquid crystal panel 100 and a data driving circuit 10. Here, the liquid crystal panel 100 includes a data line 70 for transmitting a data signal to the pixels P arranged in a matrix form. Here, the pixels P are arranged in the order of displaying red, blue, and green, and the pixels P arranged in the same column receive data signals from the same data line 70. In addition, the data driving circuit 10 selects a gray voltage to be applied to the pixel P of the liquid crystal panel 100 according to the data signal and outputs different polarities of the gray voltages output from the odd-numbered output and the even-numbered output. 30, the buffer 40 for current amplifying the gray voltage output from the decoder 30 and the odd-numbered output and even-numbered output terminals of the buffer 40 are switched to reverse polarity of the gray voltage according to a horizontal line period. It consists of a switching element 50 to be applied to the panel 100.

Here, the output terminal of the switching element 50 and the liquid crystal of the switching element 50 of the data driving circuit 10 are sequentially applied to sequentially apply the same positive or negative gray level voltage to a pixel group consisting of three red, green, and blue pixels in a row of pixels. In the wiring 20 connecting the data line 70 of the panel 100, the (3k + 1) th wiring 20 and the (3k + 2) th wiring 20 are alternated. Where k is an integer.

As a matter of course, the 3kth wiring 20 and the (3k + 1) th wiring 20 may be formed to alternate between the (3k + 2) th wiring 20 and the 3kth wiring 20.

In this case, the number of buffers 40 is one larger than the number of data lines 70 of the liquid crystal panel 100, and the inverted signal of a horizontal period may be output through switching of the switching element 50.

Accordingly, the grayscale voltage transmitted through the (3k + 2) th buffer 40 of the buffer 40 of the data driving circuit 10 through the switching of the switching element 50 is converted into the data line of the liquid crystal panel 100. When connected to the (3k + 2) th data line 70 of 70, as shown in FIG. 3, the polarity of the gradation voltage transmitted to the row of the (n-1) th pixel P is -, +, +, +,-,-,-,… … It appears as +, +, +,-,-, and the polarities of the gray voltages transmitted to the rows of the nth pixel P are +,-,-,-, +, +, +,. … -,-,-, +, +

In addition, the grayscale voltage transmitted through the (3k + 1) th buffer 40 of the buffer 40 of the data driving circuit 10 through the switching of the switching element 50 may be converted into the data line of the liquid crystal panel 100. When connected to the (3k + 2) th data line 70 of 70, the polarity of the gradation voltage transmitted to the row of the (n-1) th pixel P is + ,-,-,-, +, +, +,… … -,-,-, +, +, And the polarity of the gradation voltage transmitted to the row of the n-th pixel P is-, +, +, +,-,-,-,. … It appears as +, +, +,-,-.

In this way, adjacent output terminals are connected to an output terminal of a driving circuit which outputs signals inverted from each other, and the data line 70 applying a gray voltage to the red, green, and blue pixel rows of the liquid crystal panel 100. When two wires 20 of the three wires 20 are alternately connected to each other, the liquid crystal panel 100 can be driven like a dot inversion using a pixel group consisting of three pixels of red, blue, and green as one unit. have.

In this case, as a method of connecting the wirings 20 to each other, the two wirings 20 may be formed on different layers, but may be formed of the same layer. In addition, the position and the medium where the signal lines 20 are staggered may be used to connect the liquid crystal panel 100 and the data driving circuit 10 between the buffer 40 in the data driving circuit 10 and the output terminal of the switching element 50. A tape carrier package (TCP), a pad portion of the data line 70 of the liquid crystal panel 100, and an area outside an area where an image is displayed on the liquid crystal panel 100 may be included.

Then, the case where the wirings 20 which cross each other are formed in the same layer is demonstrated in detail.

FIG. 5 is a plan view illustrating a structure in which wirings that cross each other are formed of the same layer in the liquid crystal display according to the exemplary embodiment of the present invention.

As shown in FIG. 5, the first medium 10 is formed with a plurality of pads 61, 62, and 63 having ends wider than other portions. In addition, a plurality of pads 71, 72, 73 are formed in the second medium 70 with a wider end than the other portion. Here, the first pad 61 of the first medium 10 is the first pad 71 of the second medium 70, and the second pad 62 of the first medium 10 is the second medium 70. The second pad 72 of, the third pad 63 of the first medium 10 is connected to the third pad 73 of the second medium 70 via the wiring 20, respectively.

In this case, the three pads 61, 62, and 63 of the first medium or the three pads 71, 72, and 73 of the second medium apply signals to the red, green, and blue pixel rows of the liquid crystal panel 100. It is connected to the data line 70 or the buffer 40 which outputs the signal inverted adjacently (refer FIG. 3 and FIG. 4).

In this case, the connection portion of the first pad 71 among the pads 71, 72, and 73 of the second medium 70 may be disposed between the upper part of the second pad 72 and the second pad 72 and the third pad 73. It extends past the second pad 72. The extension of the second pad 72 also extends below the first pad 71. Thus, the signals applied to the first and second pads 61 and 62 of the first medium are sequentially transmitted to the first and second pads 71 and 72 of the second medium 70, but when output through the extension. The order is staggered,

Therefore, according to the present invention, a pixel group consisting of red, green, and blue pixels can be dot-inverted as one pixel by using a dot inversion driving circuit which outputs a signal in which odd-numbered output terminals and even-numbered output terminals are inverted from each other.

1 is an equivalent circuit for a unit pixel of a general liquid crystal display device.

2 is a block diagram illustrating a data driving integrated circuit and a pixel array of a dot inversion driving method according to the related art;

3 and 4 are block diagrams illustrating pixel arrangements of a red, green, and blue inverted data driving integrated circuit and a liquid crystal panel according to an exemplary embodiment of the present invention;

FIG. 5 is a plan view illustrating a structure in which wirings that cross each other are formed of the same layer in the liquid crystal display according to the exemplary embodiment of the present invention.

Claims (13)

A data driving circuit having an odd-numbered output stage and an even-numbered output stage for outputting image signals inverted from each other, A liquid crystal panel having a data line receiving an image signal from the data driving circuit and transferring the image signal to a plurality of pixels in a matrix form; A first pixel group consisting of n consecutive pixels among the rows of pixels is connected to an output terminal of the odd column, and a second pixel group consisting of n pixels adjacent to the first pixel group is connected to an output terminal of the even column. Liquid crystal display. In claim 1, And the driving integrated circuit is inverted at a horizontal period. In claim 2, Each data line connected to the pixels of the first pixel group is sequentially connected to an output terminal of the odd column, And a plurality of data lines connected to the pixels of the second pixel group are sequentially connected to output terminals of the even columns. In claim 3, N is three. In claim 4, The first and second pixel groups include the red, green, and blue pixels. In claim 5, The position where the data line and the output terminal are alternated may be formed in the data driving circuit, a tape carrier package (TCP) connecting the liquid crystal panel and the data driving circuit, a pad portion of the data line of the liquid crystal panel, and an image in the liquid crystal panel. The liquid crystal display device which is any one of the outside of this displayed area. In claim 6, The data line and the output terminal are connected to each other in the same layer. In claim 6, The data line and the output terminal are connected to each other in different layers. A data driving circuit having an odd-numbered output stage and an even-numbered output stage for outputting image signals inverted from each other, A driving method of a liquid crystal display device comprising a liquid crystal panel having a data line for receiving an image signal from the data driving circuit and transferring the image signal to a plurality of pixels in a matrix form. A first pixel group consisting of n consecutive pixels among the rows of pixels receives the image signal of the output terminal of the odd column, and a second pixel group consisting of n pixels adjacent to the first pixel group receives the even column. A driving method of a liquid crystal display device receiving the image signal at an output terminal. In claim 9, And the driving integrated circuit is inverted at a horizontal period. In claim 10, Each data line connected to the pixels of the first pixel group sequentially transfers the image signal to an output terminal of the odd column. And a plurality of data lines connected to the pixels of the second pixel group sequentially transfer the image signals to the even-numbered output terminals. In claim 11, N is 3, the driving method of the liquid crystal display device. In claim 12, And the first and second pixel groups are formed of the red, green, and blue pixels, respectively.