JPH04190387A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To prevent cross-talk of display data and deterioration of the uniformity of a displayed image by providing two row (horizontal) drivers for odd rows and even rows. CONSTITUTION:A column driver 1 selects a column line #4, and then an odd row line driver 2 turns on a drive transistor 13 on a row line #7 having an output XK1, and odd display data K are written in a pixel composed of a pixel electrode 501 and a pixel capacitor 502 by way of a pixel transistor 19. Further, odd display data on the third column are written from a pixel transistor 20 to a pixel 26 and from a pixel transistor 21 to a pixel 27. Thereafter, a column line #5 on G2 is selected, and an odd row line driver 3 turns on a drive transistor 16 on a column line 8 having an output XG1 so as to write even display data in a pixel 28 composed of a pixel electrode 501 and a pixel capacitor 502 by way of a transistor 22. With this arrangement, it is possible to prevent cross-talk of display data to the adjacent row line, and to prevent deterioration of the uniformity of a displayed image.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the electrical internal structure of an active matrix liquid crystal display device.

[Prior Art 1] The electrical internal configuration of a conventional active matrix liquid crystal display device is as shown in FIG. Generally, the electrical structure is such that a driver (gate selection driver) 101 and a column line driver (source line driver) 102 that selectively drives write pixels are orthogonal to each other in a matrix of one row and one column for each pixel. Met.

That is, after the row line 201 of 01 is selected by the row line driver 101, the display data is transferred to the pixel transistor 10 by the column line driver 102 via the drive transistor 103 of the X1 output column line 301.
4 is written into the pixel 105 consisting of the pixel electrode 501 and the pixel capacitor 502. Furthermore, the X2 output column line 30
The next display data is written from the pixel transistor 107 to the picture #108 via the second drive transistor 106. After repeating the above steps up to Xn, the row line 202 is selected by the G2 output of the row line driver 101, and like the row line 201, the pixel transistor 109
Display data is written to the pixel 110 via the pixel 110. Further, the same operation is performed on the row line 203, and thereafter, the same operation is repeated up to the row line Gn to complete one screen.

[Problems to be Solved by the Invention] However, with the above-mentioned conventional technology, in order to cope with the increase in size and density of liquid crystal display devices, it is difficult to incorporate a driving driver into the liquid crystal display device when the data transfer rate increases. A number of problems have arisen, such as crosstalk in display data due to an increase in gate line resistance (the data in the row that is currently being written rewrites the data in the row before the currently written row), and deterioration in the uniformity of the display screen.

Therefore, the present invention aims to solve these problems.
Even if the Kate line resistance increases due to the increase in size and density of liquid crystal display devices, the display data is An object of the present invention is to provide a liquid crystal display device that can reduce transfer speed and display data transfer speed.

[Means for solving problem y 1] The liquid crystal display device of the present invention includes a pixel electrode, a pixel transistor for driving the pixel electrode, a pixel capacitor, and a row (horizontal) arranged in parallel with the horizontal direction of the display screen. line drive line,
Column (vertical) line drive lines arranged in the vertical direction of the display screen, a row line driver for selecting and driving the row (horizontal) line drive line, and a column line driver for selecting and driving the column (vertical) line drive line. The column line driver has two lines, one for odd rows and one for even rows of horizontal lines.

Embodiment 1 FIG. 1 is an internal configuration diagram showing an embodiment 1 of the present invention.

Further, FIG. 2 is a timing chart showing a -driving method of the liquid crystal display device having the electrical internal configuration shown in FIG.

The configuration and operation will be explained in detail below using FIGS. 1 and 2.

First, the row line driver 1 selects the row line 4 of G1 according to the clock signal (CLY). .

Next, in response to the clock signal (CLXk), the odd-numbered column line driver 2 turns on the drive transistor 13 of the column line 7 of the XKI output, and the odd-numbered display data (DAT
A-K) connects the pixel to pole 5 through the pixel transistor 19.
01 and pixel capacitor 502. Furthermore, the pixel transistor 20 is connected to the pixel 2 via the drive transistor 14 of the column line 9 of the XK2 output.
The next odd number display data is written in 6. Similarly, the column line 11 of the next XK3 output is connected to the drive transistor 1.
Odd display data for the third column is written from the pixel transistor 21 to the pixel 27 via the pixel transistor 5.

After repeating the same operation up to the XKn output column, the row line driver 1 is activated by the clock signal (CLY).
2, select line 5. Next, the clock signal (CL
Xg), the even-numbered column line driver 3 turns on the drive transistor 16 of the column line 8 that outputs 28. Further, the next even number display data is written from the pixel transistor 23 to the pixel 29 via the drive transistor 17 of the column line 10 of the XG2 output. Similarly, on the next XG3 output column line 12, third column even display data is written from the pixel transistor 24 to the pixel 30 via the drive transistor 18.

After repeating the same operation up to the XGn output column, the row line driver 1 is activated by the clock signal (CLY).
3 output row line 6 is selected and the same operation as for the 01 row line is repeated.

One screen is completed by performing this series of operations up to the Gn row, but as shown in Figure 2, when the gate line resistance of the liquid crystal display device increases (as the display device becomes larger), the gate line of the pixel transistor increases. A delay occurs as in G1', 02', and G3'. As a result, in the conventional configuration, the display data being written affected the previous row line due to the gate selection overlap time a, resulting in deterioration of image quality.

However, in this embodiment, the odd-numbered rows and even-numbered rows have the configuration shown in FIG. 1, and the data timing in FIG. Even if time a occurs, the display data being written will not affect the previous row line.

FIGS. 3 and 4 show an embodiment (2) of the present invention, in which the writing (transfer) time of display data is halved by selectively driving two row lines (odd and even lines) at the same time. This figure shows the connections and drive timing that have been devised.

Now, the electrical configuration diagram shown in FIG.
The difference is that the G1 output of the row line driver 1 is connected so that row lines 4 (odd rows) and row lines 5 (even rows) can be selected simultaneously. As a result, n
This configuration is made up of a 1/2 (half) row line driver for driving a row line.

As shown in the timing chart of FIG. 4, row line 4 and row line 5 are simultaneously in the write state within the 61 selection time of row line driver 1, and odd-numbered column line driver 1'
Drive transistors (13, 14, 15) from bar 2
,...), the odd line display data of the first line is transmitted from the even line column driver 3 to the drive transistors (16, 17, 18,...) to the even line display data of the second line. Data is written (transferred) at the same time
show something

Furthermore, the row line driver 1 receives a clock signal (CLY).
When G2 is selected by
From the drive transistor (13, 14, 15,...
) to the third row odd line display data and the even line column driver 3 to the drive transistor (16
, 17, 18, . . . ), the even-numbered line display data of the fourth row is simultaneously written to the third row line 6 and the fourth row line.

By repeating the above steps, n lines of display data are written to complete one screen. However, assuming the same clock rate, the transfer and writing time spent in the above operations will be the same as in Example 1 above. It becomes half. In addition, the conventional example (
Although the simultaneous two-in drive is possible with the electrical internal configuration shown in Fig. 5), the vertical resolution is not the same as the number of horizontal lines (decreases). There is no reduction in vertical resolution (the vertical resolution is the same as the number of horizontal lines).

As explained above using the drawings, when using the electrical internal configuration shown in Figure 1, it is possible to selectively drive the row line driver every other row (the first field is an odd numbered row, the second field is an even numbered row). Interlaced drive is also possible.

Furthermore, in Examples 1 and 2, by reversing the positive and negative driving voltage phases (display data) from the odd-column line driver and the even-column line driver, the opposite phase can be achieved between the horizontal lines. Since this is the same as applying a voltage to a pixel, horizontal line inversion driving of a liquid crystal display device can be easily realized.

Also, note that the row line driver 1, odd number column line driver 2, and even number column line driver 3 in the explanation may be of the built-in type with a display device made up of a shift register, etc., or may be of the type with which a normal display device is mounted externally. Add a note.

[Effects of the Invention 1] As described above, according to the present invention, a pixel electrode, a pixel transistor for driving the pixel electrode, a pixel capacitor, and a horizontal line drive line arranged parallel to the horizontal direction of the display screen. , a column (vertical) line drive line arranged in the vertical direction of the display screen, a row line driver for selecting and driving the row (horizontal) line drive line, and a column (vertical) line driver for selecting and driving the column (vertical) line drive line. It has a matrix structure with column line drivers, and the front 8 column line drivers have two lines for odd and even horizontal rows, making it possible to increase the size and density of liquid crystal display devices. At the same time, it is possible to easily prevent problems such as difficulty in incorporating a driver into the liquid crystal display device due to the accompanying increase in data transfer speed, crosstalk of display data due to increase in gate line resistance, and deterioration of uniformity of the display screen. It also makes it possible to shorten or reduce the data transfer rate, makes it possible to easily perform horizontal line inversion driving, and has a great effect in preventing flicker.

In addition, it is possible to perform simultaneous writing scanning of two horizontal lines without reducing vertical resolution, and double-speed driving using non-interlaced scanning, as well as real-time interlaced scanning of television signals, which was difficult with conventional liquid crystal display devices. Similarly, it is now possible to easily write to a liquid crystal display device.
It is possible to realize a liquid crystal display device with excellent versatility in the drive scanning method.

[Brief explanation of the drawing]

FIG. 1 is an electrical internal configuration diagram showing one embodiment of the present invention. FIG. 2 is a timing chart for driving with the electrical internal configuration of FIG. 1 of the present invention. FIG. 3 is an electrical internal configuration diagram showing one embodiment (2) of the present invention. FIG. 4 is a timing chart for driving with the electrical internal configuration of FIG. 3 of the present invention. FIG. 5 is a configuration diagram showing a conventional example. 1... Row line driver 2... Odd column line driver 3... Even column line driver 4-6... Row lines 7-12... Column lines 13-18... Drive transistors 19-24・
...Pixel transistors 25 to 3o...Pixels and above Applicant Seiko Epson Co., Ltd. Agent Patent attorney Kizobe Suzuki (and others) CLY a a Figure 2 CLY Figure 4

Claims (1)

[Claims] A pixel electrode, a pixel transistor that drives the pixel electrode, a pixel capacitor, a row (horizontal) line drive line arranged in parallel to the horizontal direction of the display screen, and a column (vertical) arranged in the vertical direction of the display screen. a line drive line, a row line driver for selecting and driving the row (horizontal) line drive line, and a row line driver for selecting and driving the row (horizontal) line drive line;
A liquid crystal display having a matrix structure including a column line driver for selecting and driving vertical (vertical) line driving lines, the column line driver having two lines for odd and even rows of row (horizontal) lines. Device.