JPS61170778A - Active matrix color liquid crystal display panel - 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] (Industrial application field) The present invention is a color matrix liquid crystal display panel.

In particular, it relates to the pixel structure of an active matrix color liquid crystal display panel in which a switching element is arranged in each pixel.

(Prior art and its problems) Among the various flat display panels, active matrix liquid crystal display panels are particularly active in development because they are capable of large-capacity display, large-area display, color display, and low power consumption. It is.

Multicolor color display panels require display cells for 2 to 4 colors to be arranged on a plane for each pixel, and monochrome display requires 1 display cell.
Compared to configuring one pixel with a display cell, it tends to have a large capacity, a large area, and a large power consumption. Active matrix liquid crystal display panels are considered to be one of the promising candidates for solving these problems.

A general structure of an active matrix color liquid crystal display panel is schematically shown in cross section in FIG.

Force 2 - Common electrode substrate 32 provided with filter 33 and common electrode 34, each display electrode 36, switching element 37 connected to each display electrode, signal for supplying a drive signal to the switching element - and scanning line (both A field-effect liquid crystal material 35, such as a leistid nematic (TN) liquid crystal, is filled between the two substrates and an active matrix substrate 30 provided with a liquid crystal (not shown in FIG. 3). , an active matrix, display electrodes 36 on a matrix substrate 30, and color filters 3 of each color on a common electrode substrate 32.
3 are facing each other. In addition, for example, in the case of a transmissive display, there is a light source 3 on the back of the display panel.
9 and a light diffusing plate 38 are arranged, and a polarizing plate 31 is provided on the back and front of the 1 display panel.

FIG. 4 shows a partially enlarged sectional view of one display cell on the active matrix substrate side in the case where an amorphous silicon thin film transistor is used as an example of the switching element 37 provided on the active matrix substrate 30. Gates 42 corresponding to scanning lines, display electrodes 43 corresponding to pixels are formed on a glass substrate 41. Gate insulating film 44. Amorphous silicon gX45. Drain 4 corresponding to the signal line
7. Sources 46 are provided corresponding to the output terminals of the transistors and connected to the display electrodes 43, respectively. When the above configuration is completed, the glass substrate 41 becomes the active matrix substrate 30.

Actipultri cuscara with the above structure
- The equivalent circuit of a liquid crystal display panel is as shown in Fig. 5. Now, apply a scanning signal voltage with a pulse width of about 30μ@ee+12V to the gate 2-in-G 51 corresponding to the n-th scanning line. z to the mth column signal line at the same time.
For example, the pulse width of the drain line D52 is 30μse.
When an image signal voltage of approximately c+12V is applied, the conductive film transistor (TPT) 53 is switched to an ON state. Furthermore, in order to drive the liquid crystal in an alternating electric field, a direct current voltage (+6V, DC) equal to % of the absolute value of the drain voltage is applied to the common electrode 56 provided on the common electrode substrate.

In this state, the display electrode connected to the source 54 and the common electrode 56 are capacitively coupled via the liquid crystal material 55.
The image signal from the drain is applied to the display electrode through the north 54f of the thin film transistor 53 in the ON state. However, even after the transistor is turned off, the time constant of discharging through the OFF resistance of the transistor and the resistance of the liquid crystal material is very high, so the potential of one display electrode is maintained sufficiently for the frame period. If the OFF resistance of the transistor is small, it is common to separately provide a storage capacitor Cs57.

When the image signal applied to the drain line Dm is +6■ or Ov as in the above example, the liquid crystal is not in the ON state, and the light from the back light source passes through the color filter and becomes colored light, resulting in a one-color display. It will be done. On the other hand, when the image signal applied to the drain line Dm is the same as the potential of the common electrode, even if the thin film transistor is in the ON state, there is no electric field applied to the liquid crystal, so the liquid crystal is in the OFF state.

By the way, a liquid crystal display panel that displays full color using three color filters is disclosed in Japanese Patent Laid-Open No. 59-9636. According to the specification, each pixel has display cells of R (red), G (green), and B (blue) in order in the X direction as shown in FIG.
Disclosed is a liquid crystal display panel characterized in that the pixels are arranged in the X direction, and further arranged in the X direction with a pitch shifted by half of one pixel every time the pixels change one row in the X direction. It is stated that the array has "improved resolution in diagonal directions" compared to the conventional pixel array shown in Figure 6 (al).However, according to the detailed explanation in JP-A-59-9636, " When making multicolors, use R, G.

Considering the planar arrangement of color filter B,
Since R, G, and B are arranged repeatedly at each vertex of the triangle, a fairly satisfactory resolution can be achieved even in color graphics with a small number of pixels.'' However, the specification does not explain the pixel configuration method and display method regarding this. is not found.

In the embodiment of the same specification, KGB display cells are arranged in the X direction to form one pixel t-. Therefore, the length of one pixel in the X direction is about three times longer than in the Y direction, that is, considering the resolution in the X and Y directions, the resolution in the X direction is significantly inferior to that in the Y direction.

In addition, the main idea is to realize a multi-color display panel by arranging the three colors rR, G, and B in a triangular arrangement.'' However, from the description in JP-A-59-9636, it is clear that such an arrangement is not possible. It can't be achieved. TPTi in the same specification
According to the example used, an embodiment of an active matrix substrate as shown in FIG.
One color display cell is driven by a transistor 716 and a pixel electrode 717 connected to the gate line 710 and the data edge 713 in the odd-numbered row, and two transistors connected to the gate line 711 and the data line 714 in the even-numbered row. transistor 719.7
22 and two pixel electrodes 721.723. In this way, a display cell arrangement is realized in which the odd-numbered rows and the even-numbered rows are shifted by half a pitch. However, in the case of line sequential driving, R on the same gate edge,
Since information for one pixel is input to G and H, R and G
, B is arranged in a row in the X direction.

In addition, the opening does not have the triangular arrangement as mentioned in the above specification,
If the odd-numbered rows are driven by the gate line 710 and data lines 713 to 715, and a green signal is assigned to data @713, a blue signal is assigned to data line 714, and a red signal is assigned to data 4!715, display is performed. Figure 7 (- like G7
30. B731. Although R732 is displayed,
/The even numbered row is the gate line 711 and the 〇 assigned earlier.
B.

When a display is performed by driving the data lines 713 to 715 to which the R color signal is supplied, G, B, and
R has a shape in which the raw color pitch is shifted to the left, and the blue display self 31 of pixels in odd-numbered rows is half a pitch to the left in even-numbered rows.

If the blue display self 33 is shifted, the result will be as shown in Fig. 6(b).
) cannot be obtained.

As described above, in the conventional active matrix color liquid crystal display panel, it is extremely difficult to obtain a display with good resolution in the X direction and in the Y direction.

(Object of the Invention) An object of the present invention is to provide a display panel with excellent resolution by changing the arrangement structure of three color display cells constituting one pixel of an active matrix color liquid crystal display panel. .

(Structure of the Invention) A liquid crystal material is filled between two substrates, a common electrode is provided on the circular surface of one of the substrates with a size at least larger than the display surface, and a signal line is provided on the inner surface of the other substrate. and the scan line is
The IJ hooks are insulated from each other and provided in a matrix, a switching element and a display electrode are provided at each intersection of the signal line and the scanning line, and three small pieces made of small pieces are provided between the two substrates.
Primary color filters periodically move in the X and Y directions,
Two switching elements arranged on each color display cell for each color and connected to the signal line and the scanning line respectively at the intersection of the signal line and the scanning line, and two display electrodes connected to the switching element. are provided in a pair with a signal @ (scanning line) in between, and in this pair, one color display cell is connected to the signal line (scanning line).
A combination of three cells in two stages sandwiching two and one color display cells connected to the three adjacent signal lines and sandwiching the scanning line (signal line) 1. One pixel is composed of .

An active matrix color liquid crystal display panel characterized in that the display cells are arranged in opposite directions in the scanning line (signal line) direction, and the display cells are arranged in the same direction in the signal line (scanning line) direction. Structure◎ (Detailed explanation of the structure) The present invention has an active matrix color liquid crystal display panel structure, in which the structure of three color display cells constituting one pixel is changed from the conventional one in which they are arranged in a row, and a scanning It was constructed in two stages with two display cells and one display cell sandwiching a line (signal line). Information for one pixel is mixed two-dimensionally in three display cells arranged in two stages by one scanning dA (signal line) and three signal lines (scanning lines). Compared to the case where the colors are arranged in parallel in a Kr@J pattern, the aspect ratio of one pixel is close to 1, resulting in a "dot" shape, which significantly improves the resolution. Further, since adjacent pixels in the X direction or the Y direction are arranged in colors in opposite directions, there is an advantage that color moiré, in which the same color appears to be continuous in a striped pattern, is less likely to occur.

The structure of a specific panel will be explained in detail in the following embodiment using drawings.0 (Example 1) In order to explain one example of the embodiment of the present invention, FIG. 1 (1) shows an active matrix substrate. Figure (b) shows a part of the plan view of the common electrode substrate. Color filters are arranged on a common electrode substrate.

First, the active matrix substrate has scanning lines 131,
132 are arranged in the row direction, and signal lines 141 to 147 are arranged in the column direction so as to be mutually insulated and orthogonal to the scanning lines 131 and 132. Moreover, one display electrode 11 to 15 is a scanning line,
They were placed on each side of the signal line. The display electrodes adjacent to the intersection of the scanning line and the signal line are connected to each other via switching elements arranged alternately on both sides of the scanning line for each signal line, symmetrically with respect to the scanning line. ◎One display cell is made up of a pair of display electrodes with a signal line connected to the line and the scanning line ◎ Also, the display cell is made up of a pair of display electrodes that are separated by the distance of the signal line on both sides of the scanning line. Therefore, G is applied to signal lines 141-147, respectively.

When color signals of R, B, G, R, B, G, . . . are supplied, the display electrodes 1 is G, 12
The display electrodes 13, 14, and 15 have the function of displaying the colors B, G, and R, respectively, such that the signal line 143. 1449 When a signal for displaying one pixel is supplied to 145, the display electrodes 13, 14°15
One pixel is displayed by mixing three colors in a triangular arrangement.On the other hand, the color filters provided on the common substrate are arranged in a mosaic (small piece) arrangement of three colors of R, G, Be Re Gt... in the row direction. Then, the first row is shifted by 1.5 color pitch of the color filter and the row direction is 1cR,G,
A repeating mosaic arrangement of three colors (B...) is used, but the three color filters that make up one pixel are, for example, R11l, G112. B115. G 112°R1
What is the mosaic arrangement of 16 triangular pairs?

This is to correspond to the arrangement of each color display cell of the above-mentioned active matrix substrate. In order to create an active matrix color liquid crystal display panel, the above two substrates are stacked with their pixel positions aligned, and the gap between them is filled with liquid crystal material. The common electrode 20f provided on the entire surface of the area, the transfer electrode 30 provided at the tip thereof, and the transfer electrode 30 provided on the active matrix substrate are connected and assembled in the same manner as in the conventional example. In this case, the pitch size of one color display cell is set to 100μ vertically.
m, and the width was 120 μm. 60μ for one color display cell
Two display electrodes each having a size of m×80 μm are provided. One pixel that represents one color information by mixing three colors is 36,000 pixels with three display cells of 100 μm x 120 μm, such as 112°115 and 116 in Fig. 1(b).
The point has a display area of μm2. On the other hand, a conventional pixel with the same display area of 36,000 μm21<
730 in FIG. 7(b). 731゜732, so 3 pieces are lined up in parallel, so 100μ x 120μm x 3 pieces horizontally 3
60 μm or 300 μm in height, which significantly deteriorated the resolution in the long direction.In addition, conventionally, K was set to a dot shape with an aspect ratio of t-1 for one pixel. 190μ
In this case, the opening must be m x 63 μm x 3 pieces,
In order to shift the color for each row, instead of making the display cell that displays one color elongated, the number of display electrodes that display one color must be 150 μm x 23 μm x 2.
It is extremely thin and difficult to create.

In this way, when color display cells of the same size are used, the resolution can be improved in the embodiment of the present invention compared to the conventional example.Compared with the case where one pixel of the same display area is used and one color display cell pitch t is changed. Therefore, in the embodiment of the present invention, one color display is not elongated, and the active matrix substrate and the common electrode substrate can also be formed easily. Since the combinations are the same in the signal line direction, adjacent pixels will never display the same color in succession.

High quality images can be obtained without color moiré appearing as color stripes.

(Embodiment 2) Fig. 2 is a diagram showing a part of a plan view of an active matrix and a matrix substrate for explaining another example of the embodiment of the present invention.
The color filter is arranged on the common substrate, and scanning lines 231 to 236 are arranged on the co-active matrix substrate.
Arranged in the row direction, the signal lm241. 242f: The display electrodes 211 to 214 are arranged so as to be mutually insulated and perpendicular to the scanning lines 231 to 236 in the row direction. A pair of two on each side of the scanning line were provided alternately on both sides of the signal line for each scanning line so that the signal mt was symmetrical, and each was connected to the scanning line and the signal line via a switching element.

In the case of this embodiment, B and B are scanned @231 to 236, respectively.
G, R, B, G, R, B... signals are supplied.

Therefore, for the signal line 241, one display electrode 211 has the function of displaying the B1 display electrode 212, 0%, 213 the R color signal, and 214 the B color signal. Signals for displaying one pixel in 83 colors, R, G, are sequentially supplied to the scanning lines. For example, scan line 232. 233. When G, R, and B signals for one pixel are supplied at 234, the signal @242
One pixel corresponds to the color filter 220 marked with a diagonal @, and the color filter 220 with diagonal lines. Mixed colors. The method of assembling the active matrix color liquid crystal display panel, which is one pixel that displays one color information, can be carried out using a well-known method.In addition, the color filters are stacked not on the common electrode substrate side but on the other active matrix substrate side. It is also well known that it can be done on the side. Furthermore, in both the first embodiment and the second embodiment, the color filters are arranged row by row in the row (X) direction or column (Y) direction, or every column. Color filter t-1 of small pieces of three primary colors,
Instead of just arranging the five colors in a staggered manner, the three colors of one pixel in the present invention are combined in two stages, and as a result, the color filter of one color does not become elongated. is relatively easy.

The display results of the above-mentioned active matrix color liquid crystal display panel in which the present invention is implemented have significantly improved resolution because each pixel is not vertically elongated as in the conventional case. or,
In order to obtain the same level of resolution as before, it is not necessary to make each color display cell thinner, making it easier to create both the active matrix substrate and the common electrode substrate).The yield rate also improves. By reversing one combination of display cells in the line direction and making the same combination in the scanning line direction, there was an advantage that the same color did not run in a row and single color moiré did not occur. (Effects of the invention) As explained in detail, the active matrix color liquid crystal display panel of the present invention has three pixels constituting one pixel.
The arrangement structure of color display cells is such that display cells of two adjacent colors and one color are combined in two stages, connected to a common scanning line (signal@) and three signal lines (scanning?s). Since it is composed of three pairs, it is possible to obtain a display with excellent dot-like resolution.

In addition, the color signals to be supplied need only be supplied to a certain signal line (scan @) with a fixed color distribution, which simplifies the external signal processing system. The combination of display cells for one pixel is reversed in the (signal @) direction, and signal 1! ! By having the same combination in the (scanning line) direction, there is no color moire that occurs due to a row of display cells of the same color, and the display quality can also be improved. Without,
Manufacturing yield can also be improved.

- Figure 3 is a diagram showing a part of a cross section of a common electrode substrate for explaining a general active matrix color liquid crystal display panel; A partial cross-sectional view of a display cell in which a switching element is provided on a substrate, FIG. 5 is a diagram for explaining the equivalent circuit of an acte matrix color display panel, and FIG. 7(a) is a diagram illustrating a conventional active matrix substrate, and FIG. 7(b) is a diagram illustrating a display example of a display panel using a conventional active matrix substrate. This is a diagram.

In the figure s IL 12* ta, 14t 1
5*211, 212. 213. 214. 36.
43. 717,720.

721, 723. 724. 725.726 are display electrodes, 21°22, 23. 24. 25. 221
．． 222. 223,224°37, 53. 71
6. 718. 719. 722 is a switching element %131. 132. 231. 232. 233.
234°235, 236.710.711. 71
2 scans 4.141°142, 143. 144.
145. 146. 147. 241°242, 7
13. 714. 715 is a signal line, 111. 112
゜113, 114. 115. 116. 201.
202, 203. 204°205, 33. 73
0. 731. 732. 733. 734 is a color filter, 20,200, 34.56 is a common electrode, 3
0,300 are transfer electrodes, 210, 220 are 1
Pixel, 31 is a polarizing plate, 32 is a common electrode substrate, 35.55
30 is a liquid material, 30 is an active matrix substrate, 38 is a light diffusion plate, 39 is a light source, 41 is a glass substrate, 42 is a gate, and 44 is a gate insulating film.

45 is amorphous silicon film, 46.54 is north, 4
7 is a drain, 51 is a gate line, 52 is a drain twin, 53 is a thin film transistor, and 57 is a storage capacitor. -Representative Patent Attorney Susumu Uchihara, -") Figure 1 (0) 3020 (b) Figure 2 (0) (b) 21-3 times Figure 4 Figure 5 Drain line Figure 6 (a) ( b) Off diagram

Claims (1)

[Claims] A liquid crystal material is filled between two substrates, a common electrode is provided on the inner surface of one of the substrates with a size at least larger than the display surface, and signal lines and scanning lines are arranged in a matrix on the inner surface of the other substrate. are arranged in a matrix and are insulated from each other.
A switching element and a display electrode are provided at each intersection of the signal line and the scanning line, and a color filter of three primary colors consisting of small pieces is provided between the two substrates periodically in the X direction and the Y direction, each color display cell for each color. Two switching elements connected to the signal line and the scanning line, respectively, and two display electrodes connected to the switching elements are arranged at the intersection of the signal line and the scanning line. A color display cell is provided in a pair with a signal line (line) in between, and one color display cell is configured for each signal line (scanning line) on the symmetrical side of the scanning line (signal line), and connected to three adjacent signal lines. One pixel is constructed by a combination of three color display cells in two stages sandwiching a scanning line (signal line), and the combination of display cells is reversed in the direction of the scanning line (signal line). 1. An active matrix color liquid crystal display panel characterized in that the display cells are arranged in the same combination in the signal line (scanning line) direction.