常见的液晶显示（Common LCD display）.doc

常见的液晶显示（Common LCD display） (1) twisted nematic (TN, Twisted, Nematic); (2) super twisted nematic (STN, Super, TN); (3) double layer super twisted nematic (DSTN, Dual, Scan, Tortuosity, Nomograph); (4) thin film transistor type (TFT, Thin, Film, Transistor). The basic display principle of TN - LCD, STN - LCD and DSYN - LCD is the same, but the twist angle of liquid crystal molecule is different. The twist angle of liquid crystal molecules STN LCD is 180 degrees and 270 degrees. While using different ways and TFT-LCD display TN series LCD. Its specific working principle is shown below: 1, TN model is the most basic display technology in liquid crystal display, and then other types of liquid crystal display is also based on TN type to improve. And it works in simpler ways than other technologies. Please refer to the pictures below. The simple structure of the TN LCD is shown in the figure, which includes vertical and horizontal polarizer, alignment film with fine grain groove, liquid crystal material and conductive glass substrate. In the absence of an electric field, the incident light passes through the polarizer and rotates 90 degrees through the liquid crystal layer, where the polarized liquid crystal layer is twisted by molecules. After leaving the liquid crystal layer, the polarization direction exactly with another polarizing plate in the same direction, so the light can pass smoothly, the electrode surface is bright. When the electric field is added, the optical axis shift of each liquid crystal molecule is in accordance with the electric field direction. The liquid crystal layer has lost rotation ability, results from the incident polarizing polarizer, polarization direction of the polarizer direction and the other vertical relationship, and can not pass, this electrode surface appears dark state. The TN type imaging principle is that the liquid crystal material is placed between two transparent conductive glass attached to the vertical polarizer of the optic