Image display device

Abstract

On a termination side of each scanning line is provided a charging switching element and a discharging switching element in parallel with each other, the charging switching element having a gate electrode which is connected with one end of a scanning auxiliary line, the other end of which is connected to a scanning line of the same stage, the discharging switching element having a gate electrode which is connected with one end of a scanning auxiliary line, the other end of which is connected to a scanning line of the following stage. Further, the charging switching element has a source / drain electrode which is connected to a scanning line and a selected state scanning driving voltage power source, whereas the discharging switching element has a source / drain electrode which is connected to a scanning line and the non-selected state scanning driving voltage power source, thereby allowing an image display device of the present invention to suppress the dull waveform of a driving voltage at both rise and fall, and prevent erroneous writing without reducing effective writing time.

Description

technical field [0001] The present invention relates to a display device that performs liquid crystal display or EL (Electro-Luminescence; electroluminescence) display, etc., and particularly relates to a display device using active matrix (active matrix) drive. Background technique [0002] Schematic cross-sectional views showing the structure and operation of the liquid crystal display device are shown in FIGS. 7( a ) and 7 ( b ). [0003] The structure of the above-mentioned liquid crystal display device is as shown in FIG. After the alignment films 1003 and 1013 were formed, rubbing was performed on the alignment film 1003 side in a direction parallel to the paper surface, and on the alignment film 1013 side, rubbing was performed in a direction perpendicular to the paper surface. Then a sandwich structure of two glass substrates 1001 and 1011 is formed with the electrodes 1002 and 1012 as the inner side, and a Twisted Nematic liquid crystal material is filled therebetw...

AI Technical Summary

Problems solved by technology

[0019] For such a problem, the method used in the past is to reduce the wiring resistance by increasing the width of the wiring, increasing the thickness of the wiring film, and changing to a low-resistivity wiring material. However, the problem with this method is that , due to the increase in the width of the wiring, the proportion of the area occupied by the wiring part in the pixel will increase, and the opening part through which the light passes will decrease

Therefore, there is a problem that the TFT1051 on the terminal side does not reach the writing voltage within the writing time and remains off, so the charging is still insufficient and the writing ends

In addition, the problem in a display device with high resolution and short writing time is that the set bias time is not enough, and it is impossible to prevent wrong writing and insufficient writing at the same time, so the display quality is reduced.

Therefore, both methods have the problem of increased cost due to increased number of parts and increased assembly time

[0031] Moreover, the liquid crystal display device described in the above-mentioned Japanese Unexamined Patent Application Publication No. 10-253940 can suppress the problem that the falling edge of the scanning driving voltage waveform changes gently, thereby avoiding erroneous writing, but it does not take into account the problem of suppressing the gradual change of the rising edge. Therefore, the rise delay when the pixel switching element is turned on, the effective writing time is reduced, and the occurrence of insufficient charge of the display pixel cannot be avoided.

[0032] In addition, in the liquid crystal display device described in the above-mentioned Japanese Patent Laid-Open No. 10-253940, the grid itself of the switching element for discharging is connected to the terminal side of the scanning line of the next stage, so its rising delay is changed from the non-selected The voltage applied by the scanning drive voltage power supply cannot work quickly, and a good improvement effect cannot be expected

[0033] In addition, the above-mentioned problems are not unique to liquid crystal display devices. For example, other active matrix image display devices using TFTs as switching elements such as EL display devices also have such problems.

Images