JPS604976A - Electrode construction of liquid crystal display - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a multiline matrix type multilayer liquid crystal display device capable of displaying a large amount of information, and particularly to its electrode structure.

<Prior art> In an XY matrix display device that uses the optical effect of liquid crystal to drive the display via orthogonal scanning side electrodes and signal side electrodes, it is necessary to display a large amount of information. XY
It becomes necessary to increase the number of electrodes that make up the matrix electrode structure. In this case, not only the number of signal-side electrodes but also the number of scanning-side electrodes increases, and the period allocated to one scanning-side electrode within a certain frame frequency decreases, resulting in a decrease in display contrast. Therefore, the following method (1) or (2) has been proposed as a means for maintaining good display quality when driving a matrix type liquid crystal display device that is required to display a large amount of information.

(1) Active matrix method in which switching elements such as thin film transistors are placed directly at the intersections of electrode lines arranged orthogonally in the X and Y directions.

(2) A voltage averaging method that optimizes the bias voltage to maximize the effective voltage applied to the liquid crystal when the voltage is turned on and off.

In the method (1) above, it is possible to perform essentially static driving, and a sufficient voltage is applied when turned on, so good display contrast can be obtained, but on the other hand, the process of forming thin film transistors at the intersections of the XY electrode lines is extremely complicated. Therefore, there is a problem that it is difficult to form a switching element having uniform characteristics between each intersection point. On the other hand, the method (2) above attempts to improve the contrast by changing the voltage application method, and requires almost no changes to the structure of the liquid crystal display cell itself. However, recently a method has been developed in which the number of electrodes that can be effectively scanned is increased by optimizing the bias voltage and improving the electrode structure of the liquid crystal display cell, and its effectiveness has been confirmed. By improving the electrode structure, the number of electrodes that can be scanned can be dramatically increased, and by applying an optimal bias voltage, it is possible to drive a large amount of information to clearly display it.

There are methods for improving the electrode structure as shown in FIGS. 1 to 6. FIG. 1 shows what is called an electrode upper and lower split method, in which the signal side electrode is the upper half electrode Yl.

Y2. ..., Yn and the lower half electrode Y1. Ymu...
Y′n, scanning side electrodes X1. X2. ..., Xm
is used as a common electrode between the upper and lower half of the signal side electrode. Figure 2 shows what is called a double matrix electrode system, in which two signal side electrodes Yj, Yj+1 are inserted into one scanning side electrode xH in a comb-like shape, and the adjacent two
It consists of individual picture elements. FIG. 3 shows what is called a two-layer liquid crystal cell system, in which two liquid crystal panels are stacked one on top of the other and each is individually driven to display about half of the screen. Fig. 4 shows a so-called two-layer electrode system, in which an insulating film is partially provided on the lower signal side electrodes yi, y'', and on the inner surface of the same substrate, and the upper signal side electrodes Yl, Y2, ... is the lower signal side electrode Y〒2%.

By arranging the signal side electrodes in an overlapping manner, the upper and lower signal side electrodes are individually driven. In addition, each of the above methods can be used alone or in combination.

In FIG. 5, a combination of a double matrix electrode method and an upper and lower electrode division method is used. Still, FIG. 6 uses a combination of the two-layer liquid crystal cell method and the upper and lower electrode division method. However, in these cases, the display section is divided into four blocks, and electrode extraction is performed using all four directions. Therefore, if the number of display layers is increased beyond this value, it will become impossible to take out the electrodes unless multi-layered. Multilayering of electrode lead lines is very complicated and reduces reliability.

<Object of the Invention> The present invention provides a multi-line matrix type liquid crystal display device capable of displaying a large amount of information, by subdividing the display screen into a large number of blocks to reduce the number of electrodes to be scanned, thereby improving the operating margin in driving. It is an object of the present invention to provide a liquid crystal display device with increased display contrast and improved display contrast.

<Example> FIGS. 7 and 8 are diagrams showing the arrangement of electrodes on the cell substrate of a two-layer cell type liquid crystal display device explaining one example of the present invention. FIG. FIG. 8 corresponds to the lower layer liquid crystal cells, respectively. Further, the number of scanning side electrodes constitutes a matrix of 16 lines, and the number of signal side electrodes constitutes a matrix of n lines.

In the upper layer liquid crystal cell, as shown in FIG. 7, the first group of X to X4 and the third group of X9 to X12 are used as scanning side electrodes.
A signal side electrode Yl is arranged on the scanning side electrode of the first group.
, Y2. , Yn, and signal side electrodes Yl, Y2 . ..., Yn are arranged facing each other in the intersecting direction. In the lower layer liquid crystal cell, the eighth
As shown in the figure, the second group of scanning side electrodes X5 to X8 and the fourth group of Xi3 to Xi6 are arranged, and the scanning side electrodes of the second group include signal side electrodes Y〒 YN, ..., YH, and The fourth group of scanning side electrodes includes signal side electrodes Yl, Y2. ..., Y
They are arranged facing each other in the direction that n intersects. In the upper layer liquid crystal cell, there is a second electrode between the first and third groups of scanning side electrodes.
There is a space corresponding to each group, and similarly, a space corresponding to the fourth group is provided below the third group.

Within this space, the signal side electrodes Yl, Y2 . . . , Yn are all bent in the right angle direction and arranged parallel to the scanning side electrodes xl to x4, and the electrodes are taken out from the same direction as Xi to X4. Similarly, the signal side electrodes Yl, Y2 . ..., Yn are all bent in the right angle direction in the space corresponding to the fourth group of scanning side electrodes, and are arranged parallel to the scanning side electrodes X9 to X12 to take out the electrodes. In the lower layer liquid crystal cell, contrary to the above two-layer liquid crystal cell, there is a space equivalent to the first group above the second group of scanning side electrodes, and a space corresponding to the first group is provided between the second group and the fourth group. There is space for three groups. Using these spaces, signals facing the scanning side electrodes of the second group (fl, 11th electrode Yl, Y2..., Yn, and signals facing the scanning side electrodes of the 44th group) in the same way as in the upper layer liquid crystal cell. Side electrodes Yl, Y2...
.

All Yn are bent at right angles, and the electrodes are taken out from the same direction as the scanning side electrodes.

The first to fourth groups of scanning side electrodes constitute a display screen consisting of four blocks, and each block is arranged alternately.
It is distributed between the two layers and the lower layer liquid crystal cell.

Although the display screen is divided into four blocks in this embodiment, it is also possible to divide it into a larger number of blocks depending on the number of scanning side electrodes. Increasing the number of blocks means that the number of scanning electrodes per I block decreases, and when the number of scanning electrodes is constant, it becomes possible to scan more lines. Each block is arranged alternately in the upper and lower liquid crystal cells, and the space created by this is used to bend the signal-side electrode and take out both electrodes from the same direction. Capacity information can be displayed.

FIG. 9 is a diagram showing the arrangement of electrodes in a two-layer cell type liquid crystal display device explaining another embodiment of the present invention. Number of electrodes on scanning side is 30
The number of electrodes on the 0 line and the signal side constitutes a matrix of n lines.

If 30 scanning side electrodes constitute one block, it is divided into 10 blocks. Odd block XB as shown in the left half of Figure 9
I, XB3, ..., XB9 are provided in the upper layer liquid crystal cell, and even number blocks XB2,
B4, . . . , XBIQ are arranged in the lower layer liquid crystal cell. In addition, signal side electrodes Yl, Y2, .
. . , Yn is bent at right angles and arranged in the same direction as the scanning side electrodes, and the electrodes are taken out.

Figures 10 (A) and (B) are configuration diagrams showing the structure of a liquid crystal cell substrate to which the electrode configuration shown in Figure 9 is applied. ○The signal side electrode is bent at each space, and further has two The electrode arrangement has been expanded to a pinch, making it easier to connect electrodes and leads. On the inner surface of the upper substrate are odd numbered blocks of scanning side electrodes XBI, XB3,...
XB9 is arranged, and the signal side electrodes (Yl, Y2 + one layer Yll), (Yl
, Y2 , ・+, y, , ), ・, (Yl , Y
2, -, Yn) are arranged. In addition, even numbered blocks XB2 and XB4 of scanning side electrodes are arranged on the lower surface of the central board.
, .
, (Yl, Y2, "・, Yn),"'.

(yl, Y2, ., Yn) are arranged. Twisted nematic field-effect liquid crystal is filled between each substrate, and matrix display based on orientation change of liquid crystal molecules is performed via a two-layer liquid crystal cell.

In addition, although the above embodiments are mainly explained with a two-layer liquid crystal cell method, other methods such as an upper and lower electrode split method, a double electrode method, an IJ wax electrode method, and a two-layer electrode method can be added to achieve even more multi-driving. It can also be configured to do this.

<Effects of the Invention> As detailed above, according to the present invention, multi-line multiplex driving is possible by combining block groups with a relatively small number of scanning electrodes, and good contrast is ensured when displaying a large amount of information. be able to. Furthermore, there is no limit to the number of blocks into which the screen is divided, so the number of scanning electrodes can be reduced and the operating margin when voltage is turned on and off can be set large.

[Brief explanation of drawings]

1 to 6 are configuration diagrams showing various electrode structures applied to conventional liquid crystal display devices. FIGS. 7 and 8 are electrode arrangement configuration diagrams illustrating one embodiment of the present invention. FIG. 9 is an electrode arrangement configuration diagram illustrating another embodiment of the present invention. FIG. 1O is a configuration diagram of a liquid crystal cell substrate to which the electrode structure of FIG. 9 is applied. xl::(X2,...,X16...Scanning side electrode, Y
l, Y2.・110 Yn-・Signal side electrode, XBI, XB2, ・-, XB
IQ - Scanning side electrode block. Agent Patent attorney Aihiko Fuku (2 others) Yt Y2
Yn Yt')', 2'' or Fig. 1; Fig. 3 Y7 layer Fig. 2 Fig. 5- and l' Fig. 7 Fig. 8

Claims (1)

[Claims] 1 At least two layers of liquid crystal cells are stacked, one electrode group constituting a matrix electrode is cut into a plurality of blocks, and each block is alternately arranged on the two layers of liquid crystal cells, and the matrix electrodes are A liquid crystal display characterized in that the matrix electrodes are arranged in parallel by arranging the other electrode group to face each other and bending their ends in the space between the blocks outside the opposing area, so that the electrodes are taken out from the same direction. Electrode structure of the device.