JPH0756540B2 - Driving method of active matrix type multicolor display device - Google Patents

Description

Detailed Description of the Invention

TECHNICAL FIELD The present invention relates to a configuration and driving method of an active matrix type multicolor display device using a display element such as liquid crystal. (Prior Art) FIG. 3 shows an example of a display element matrix in a conventional active matrix type multicolor display device. Reference numeral 1 is a thin film transistor (hereinafter referred to as TFT), 2 is a display element, and the TFT 1 and the display element 2 form a display cell 3. The display cells 3 are arranged in a matrix. The gate of TFT1 is connected to the gate lines G1 to G3. The source of the TFT1 is connected to the signal lines S1 to S5, and the drain is connected to the display element 2. As the display element 2, here, a liquid crystal having a color filter is assumed. When the gate line is selected and becomes a high voltage, the TFT1 connected to it becomes conductive, and the display signal applied to the signal line is transmitted to the display element 2. If the display signal is logic [1] (high voltage), the display element 2
Displays the color of the filter. Display signal is logical

If [0] (low voltage), black is displayed. In Fig. 3, the letters R, G, and B are red and
A display element for displaying green and blue is shown, and R, G, and B form one set to form a pixel 4. This pixel is red, blue,
Eight colors are displayed by a combination of display signals transmitted to the green display element. However, if the display elements 2 in the pixel 4 are arranged in a horizontal row as shown in FIG. 3, the red and green display elements are spaced apart from each other, so that color mixing is less likely to occur and good display cannot be performed. It was In addition, the number of display elements required in the horizontal direction is three times that of a black-and-white display device. Therefore, when the display elements having the same area are used, the vertical and horizontal resolutions are different. Therefore, a display device as shown in FIG. 4 has been proposed in which the arrangement of the display elements in the pixel is Δ type. FIG. 4 shows an example of an arrangement of conventional 1-pixel display elements. The TFTs, display elements, signal lines, and gate lines in FIG. 4 are the same as those in FIG. 3 and are given the same numbers. With such an array of display elements, red, blue, and green colors can be mixed well, and good display can be performed. The vertical and horizontal resolutions are also the same. However, as is clear from FIG. 4, the same gate line in which independent signal lines are wired to the TFT1 corresponding to each display element in the pixel is wired to the gate of each TFT in the pixel. Therefore, the wiring of signal lines and gate lines becomes complicated. As a result, the area occupied by the wiring portion is increased, and the area of the display element is reduced, resulting in poor display quality. Further, there is a drawback that the cross portion of the wiring increases and the manufacturing yield decreases. (Object of the Invention) An object of the present invention is to provide a Δ-shaped or L-shaped display element in which red, blue and green colors in a pixel can be mixed well and the vertical and horizontal resolutions can be the same. In order to solve the complicated wiring of signal lines and gate lines,
An object of the present invention is to provide a method of transmitting a display signal to a display element, which can be a simple signal line or a gate line. (Structure of the Invention) In the present invention, a plurality of gate lines and a plurality of signal lines are arranged in a matrix, and a red, blue, or green display is provided at an intersection of the gate lines and the signal lines via a thin film transistor. Red, blue, and green display elements, each of which has three elements out of the four display elements configured by the two adjacent gate lines and the two adjacent signal lines. A driving method of an active matrix type multi-color display device configured as described above, wherein display signals are transmitted to the three display elements forming the pixel, and the two gates are used during scanning of an odd-numbered frame. One of the lines is selected, a display signal is transmitted to the display element connected to the gate line among the three display elements via the signal line, and the two gate lines are supplied during scanning of an even-numbered frame. Select the other of
By transmitting a display signal to an unselected display element connected to the gate line among the three display elements through the signal line, the pixel is configured by two consecutive frame scans. A display signal is transmitted to each display element. The conventional method, in which three independent signal lines are wired to each of red, blue and green display elements in a pixel, is different from the method of transmitting a display signal. (Embodiment) FIG. 1 is a diagram for explaining a first embodiment of the present invention. In this embodiment, the TFT, the display element, the signal line, and the gate line are the same as those in FIG. 3 and are denoted by the same numbers. The difference from FIG. 3 is that the display element of 2 rows and 3 columns is divided into two L-shaped pixels 10 and 11, and the arrangement of the red, blue and green display elements in the pixel is changed accordingly. is there. By arranging such pixels in a matrix, the wiring of the signal line and the gate line becomes a simple wiring as in FIG. With this configuration, it is impossible to simultaneously transmit display signals to the red, blue, and green display elements in the pixel, unlike the conventional case.
Therefore, in the present invention, the display signal is transmitted by the following method. The transmission of the display signal to the display element is performed row by row through the signal lines by sequentially selecting the gate lines. When the odd-numbered gate line G1 is selected to have a high voltage, the blue (B) display signal of the pixel 10 is supplied to the signal line S1 and the pixel 11 is supplied to S2.
The red (R) display signal and the green (G) display signal of the pixel 11 are transmitted to S3. Next, when the even-numbered gate line G2 is selected and set to a high voltage, the red (R) display signal of the pixel 10 is supplied to the signal line S1, and the green (G) display signal of the pixel 10 is supplied to S2. The blue (B) display signal of the pixel 11 is transmitted to S3. That is, display signals of different colors within the same pixel or between adjacent pixels are transmitted to the same signal line in time division in synchronization with the selection of odd-numbered and even-numbered gates. In this way, by sequentially selecting the gate lines and transmitting the display signals to the signal lines, the predetermined display signals are transmitted to all the display elements. FIG. 2 is a configuration diagram in the case where interlaced scanning of gate lines is performed and a display signal is transmitted to a display element for one screen by two scans of an odd-numbered frame and an even-numbered frame. Reference numeral 20 is a matrix of the display elements shown in FIG. Gate line
G1 to Gn are connected to the gate line selection circuit 21. Signal line S1
~ Sm are connected to the shift register 30. Further, a signal selection circuit 40 is added to the input section of the shift register 30. In this embodiment, the gate line selection circuit sequentially selects and scans only odd-numbered gate lines when scanning odd-numbered frames. When scanning even-numbered frames, only even-numbered gate lines are selected and scanned. When scanning an odd-numbered frame, only the display signal transmitted to the display pixel corresponding to the odd-numbered gate line is selected by the signal selection circuit.
Select at 40 and input to shift register 30. Similarly, when scanning an even-numbered frame, only the display signal transmitted to the display pixel corresponding to the even-numbered gate line is selected by the signal selection circuit 40 and input to the shift register 30 '. Therefore, the transmission of the display signal to the display element of one screen is completed by scanning the gate line twice in consecutive frames. That is, in this embodiment, since the interlace scanning of the gate line is performed, the hardware amount of the shift register is reduced by half, and
If the scanning speed is the same, the transmission speed of the display signal and the operation speed of the shift register are halved. As a result, the power consumption is halved. Although the display elements in the pixels are arranged in the L shape in the above embodiments, the arrangement and operation are substantially the same even if they are arranged in the Δ shape, and they can be easily realized. The same applies to the arrangement of the display elements for each color of red, blue, and green in the pixel which is different from that of the above embodiment. Although liquid crystal is assumed as a display element in the above embodiments, the same applies to other display elements such as EL. Further, in the above embodiment, two signal lines are used for three display elements of one pixel to transmit the display signal in a time division manner. However, the display signal is transmitted in a time division manner using one signal line. It is also possible to transmit easily. In the above description, the display signal is assumed to be digital, but the operation is the same with an analog signal. (Effects of the Invention) As described above, according to the configuration and the display signal application method according to the present invention, the arrangement of the display elements capable of excellent color mixing is set to a small amount without complicated wiring of signal lines and gate lines. There is an advantage made possible by adding hardware. Therefore, according to the present invention, a display having good display quality can be realized with a good manufacturing yield. Further, by performing the interlace scanning of the gate lines, there is an advantage that the amount of hardware, power consumption can be reduced and the transmission speed of the shift register can be reduced. Therefore, when the present invention is applied to a large-area and high-definition dot matrix type multicolor display, the effect is extremely great.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the first embodiment of the present invention, FIG. 2 is a configuration diagram for performing interlaced scanning of gate lines, and FIG. 3 is a display element in a conventional active matrix type multicolor display device. An example of a matrix, FIG. 4 is an example of an arrangement of conventional display elements for one pixel. 1 ... Thin film transistor (TFT), 2 ... Display element, 3 ... Display cell, 4,10,11 ... Pixel, 20 ... Display matrix, 21 ... Gate line selection circuit, 30 ... Shift register, 40 …… Signal selection circuit, S1 to Sm …… Signal line, G1 to Gn …… Gate line.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyoshi Masuda 3-9-11 Midoricho, Musashino-shi, Tokyo Inside Nippon Telegraph and Telephone Corporation Musashino Telecommunications Research Laboratories (56) Reference JP-A-59-9636 (JP, A) )

Claims (1)

[Claims] 1. A plurality of gate lines and a plurality of signal lines are arranged in a matrix, and a display element of red, blue, or green is arranged at an intersection of the gate lines and the signal lines via a thin film transistor. , Of the four display elements composed of the two adjacent gate lines and the two adjacent signal lines, each of which is made up of red, blue, and green display elements with three as one pixel. A method of driving an active matrix multicolor display device, wherein one of the two gate lines is used to transmit a display signal to the three display elements that form the pixel when scanning an odd-numbered frame. Select the above 3
The display signal is transmitted to the display element connected to the gate line among the display elements via the signal line, and the other of the two gate lines is selected when the even-numbered frame is scanned, By transmitting a display signal to an unselected display element connected to the gate line among the display elements through the signal line, the three of the three elements that form the pixel by two consecutive frame scans are transmitted. A method for driving an active matrix type multicolor display device, which comprises transmitting a display signal to a display element.