JPH0355811B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid crystal display having matrix pixels.

FIG. 1 shows a conventional dot matrix type pixel arrangement. Usually n lines on the X side, m on the Y side
They are arranged in a matrix of columns, and are composed of (n×m) pixels as a whole, and display characters and the like. This pixel is driven using a drive method called voltage averaging method, multiplex drive in which lighting and non-lighting data is driven from the X-side electrode to a line selected by the Y-side electrode, and thin film transistor (TFT) drive. This is performed using an active matrix method in which charges are accumulated and driven in pixels via non-linear elements. With the recent development of computers, liquid crystal displays are increasingly being used in their terminals. Also, it takes advantage of the low power consumption and flatness of liquid crystal display panels.
There has been a demand for a display comparable to a CRT.
As a result, the possibility of displaying not only simple characters but also graphics and color is being pursued. Moreover, when it comes to graphics, display resolution becomes a big problem. However, it is difficult to increase the resolution with a simple X-Y parallel arrangement of pixels as shown in FIG. 1, which is especially a big problem when realizing a multi-color display.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a means for improving the resolution in graphic displays and the like, particularly in multicolor graphic displays.

FIG. 2 is a basic conceptual diagram showing the pixel arrangement of the present invention. A is a method of shifting every other step by half a pitch in the X direction, and B is a method of shifting every other step by a half pitch in the Y direction. Since the resolution of pixels in this arrangement improves in the diagonal direction, diagonal lines do not appear unnatural in graphics even in monochrome, and a considerable visual resolution can be obtained even with the smallest number of pixels. Also, when creating multi-colors, considering that the R, G, and B color filters are arranged on a plane, R, G, and B are arranged repeatedly at each vertex of the triangle, so even color graphics can be satisfied with a small number of pixels. It is possible to achieve high resolution.

FIG. 3 is an example of an application of the present invention in a multiplex driving method. To achieve the arrangement shown in Figure 2A, wire the X electrodes by shifting them by half a pitch every other row. Here, the X electrode and the Y electrode are usually made of transparent conductive electrodes, and if necessary, a wiring material of a minute width made of a metal thin film may be arranged in order to lower the wiring resistance.

To increase display resolution, increase the number of pixels.
Therefore, as an alternative to conventional multiplex driving, there is a method of using TFTs to improve the number of lines due to the charge storage effect. FIG. 4 shows a pixel 5 using TFT. The gate line 4 turns on the thin film transistor (TFT) 1, the data line 3 writes lighting or non-lighting data to the pixel, that is, the liquid crystal 2, and then the gate line 4 turns the TFT 1 off.
Then, the charges written in the liquid crystal 2 are accumulated and driven.

FIG. 5 shows an arrangement method for improving resolution according to the present invention using TFT. Data line 13~
15, consists of gate lines 10 to 12, and the odd-numbered columns have a normal arrangement such as a transistor 16 and a pixel electrode 17, while the even-numbered columns have transistors 19 and 22 and pixel electrodes 21 and 2 for the data line 14.
Arrange them in parallel as shown in 3, and essentially shift them by half a pitch. In this example, the wiring material of the data lines 13 to 15 and the drive electrodes 17, 20, 21, 23 are formed in the same layer or on the same layer, but if the data lines and the drive electrode overlap If the structure is acceptable, the pixel electrode 24 may be shifted as is, even though the transistor 25 is set as a single transistor and shifted by half a pitch as shown in FIG.

FIG. 7 shows another specific example of the present invention using TFT, in which the data lines 30 to 32 are arranged in a zigzag pattern and shifted by half a pitch. The purpose of this method is that the pixel configurations of the areas shifted by half a pitch and those not shifted by a half pitch are completely the same, and the unnaturalness caused by shifting by half a pitch is eliminated.

FIG. 8 is a specific example corresponding to the method shown in FIG. 2B using TFT. For data lines 40 to 42 and gate lines 43 to 45, odd numbered columns are transistors 46 and 48 and drive electrodes 47 and 49.
are arranged as usual, but in even-numbered columns, pixels are arranged in parallel above and below the gate line. For example, by gate line 44, transistors 48, 50, 5
1 is turned ON, data is written to the drive electrodes 49, 52, and 53, and pixels shifted by half a pitch are driven. In this case, similar to FIG. 6, if the drive electrode 58 is overlapped with the gate line 56 as shown in FIG. 9, the effect will be further improved.

FIG. 10 shows a method in which the gate lines 63 to 65 are arranged in a zigzag pattern to shift the drive electrodes by half a pitch, and the effect is the same as that in FIG. 7.

FIG. 11 shows yet another example of arrangement using TFT. The drivers 70 to 73 have data lines 77, 79,
81, 83, and data line 7.
8, 80, 82 are set to Y by switches 74 to 76.
Each line of side scan is connected alternately to the right or left. For example, when the gate line 84 turns on the TFT and the switches 74 to 76 are tilted to the left, the same data is written in pairs of pixels 89 and 90, and 91 and 92, respectively. Next, the gate line 84 turns the TFT OFF, the gate line 85 turns the TFT ON, and the switch 7
When pixels 4 to 76 are tilted to the right, the same data is written in pairs of pixels 94 and 95, 96 and 97, and 98 and 99, thereby realizing the method shown in FIG. 2A.

In the specific examples shown in FIGS. 5 to 11, three types of R, G, and B color filters are naturally arranged at each drive electrode (pixel) according to the principle shown in FIG. Naturally, the same color filters are assigned to the pixel pairs to which the same data is written, for example, 89 and 90 in FIG. 11, R (red), G (green), B (blue).
The three primary colors are arranged in a triangle to realize a multicolor display panel.

Furthermore, as a means to realize high-resolution panels,
There is a drive method that uses nonlinear elements that is similar to TFT drive. FIG. 12 shows the configuration of a pixel 100 using a nonlinear element 103. Timing line (corresponding to the Y electrode in Figures 1 and 3) and data line 102
A nonlinear element 103 is used to drive the liquid crystal 104 between
The nonlinear element has low resistance under high voltage and high resistance under low voltage, and a high voltage is applied between the data line 102 and the timing line 101 to send the lighting data to the nonlinear element in a low resistance state. In this method, the nonlinear element is put into a high resistance state by applying a low voltage, and the pixel charge is accumulated and driven. Specifically, this nonlinear element is Ta or
The most commonly used structure is a structure in which an oxide film of Nb, Ti, etc. is sandwiched between metal electrodes.

FIGS. 13 to 15 are examples of configurations of high-resolution pixels using nonlinear elements. In this figure, the scanning Y
Although the side electrodes are omitted, they actually exist across the liquid crystal layer as shown in FIGS. 1 and 3.

In FIG. 13, pixels (drive electrodes) 110, 112, and 114 are configured for data lines 105 to 108 via nonlinear elements 109, 111, and 113. Nonlinear elements 111 and 113 connected in parallel to data line 106 cause drive electrodes 112 and 1
The same data is written in 14, and as a result, the electrode configuration shown in FIG. 2A can be realized.

In Figure 14, the data lines 111, 112, and 113 are wired in a zigzag pattern, so the second
The configuration is shown in Figure A.

FIG. 15 shows a method that uses pixels efficiently, that is, increases the drive electrode ratio and eliminates the unnaturalness caused by half-pitch shift. Data line driver 12
0 to 123 are directly connected to data lines 127 to 130, and data lines 131 to 134 are connected to switch 12.
4 to 126, the connection point to the driver is switched for each scanning Y electrode. For example, when an odd-numbered scan electrode is selected, the switch 124
~126 is tilted to the left, so the drive electrode 13
6 and 137, and 138 and 139 form a pair and the same data is written. On the other hand, when an even-numbered scanning electrode is selected, the switches 124 to 126 are tilted to the right, and 141 and 142, 143 and 144, and 145 and 146 form pairs and write the same data. As a result, the electrode configuration equivalently becomes as shown in FIG. 2A.

Also in FIGS. 13 to 15, a multicolor display can be realized by assigning and arranging color filters to each drive electrode. For example, the 15th
In the illustrated example, the drive electrodes 136 and 137 have R, 14
G color filters are assigned to 1 and 142, and B color filters are assigned to 143 and 144, and the color filters are arranged above or below the drive electrode.

As described above, in the present invention, a liquid crystal is sealed within a pair of substrates, a plurality of pixel electrodes are formed in a matrix on the substrates, color filters corresponding to the pixel electrodes are arranged, and the pixel electrodes are In a liquid crystal display device connected to a data line or a scanning line through a thin film switching element, each of the pixel electrodes is shifted by a half pitch in the matrix pitch from one row to the next in the row direction or one column to the other in the column direction. The pixel electrode is divided into two parts around the data line or scanning line, and the divided pixel electrode is supplied with an image signal from the same data line or scanning line through the switching element. Therefore, even if the pixels are shifted by half a pitch, the scanning line or the data line can form a straight line without having to be bent, and pixel defects can be minimized.

[Brief explanation of drawings]

FIG. 1 shows the pixel configuration of a dot matrix panel, which is a conventional liquid crystal display, and FIGS. 2A and 2B show the basic configuration of a high-resolution pixel (drive electrode) of the present invention. FIG. 3 shows an example of the drive electrode configuration of the present invention in multiplex drive. Further, FIG. 4 shows the configuration of a pixel using a thin film transistor, and FIGS. 5 to 11 show examples of realizing a high-resolution pixel of the present invention using the thin film transistor. Furthermore, the first
FIG. 2 shows the configuration of a pixel using a nonlinear element, and FIGS. 13 to 15 show examples of realizing the high-resolution pixel of the present invention using a nonlinear element. 1...Thin film transistor, 103...Nonlinear element, 70-73, 120-123...Data line driver.

Claims (1)

[Claims] 1 A liquid crystal is sealed in a pair of substrates, and a plurality of pixel electrodes are formed in a matrix on the substrates,
In a liquid crystal display device in which a color filter corresponding to the pixel electrode is disposed, and the pixel electrode is connected to a data line or a scanning line via a thin film switching element, each of the pixel electrodes is arranged in a row-by-row direction. or the matrix pitches are arranged in a column direction so as to be shifted by half a pitch from one column to another, and the pixel electrode is divided into two parts with the data line or scanning line as the center;
A liquid crystal display device characterized in that the two divided pixel electrodes are supplied with an image signal from the same data line or scanning line via the switching element.