TFT (Thin Film Transistor) LCD, or Thin Film Transistor LCD, is one of active matrix type liquid crystal displays (AM-LCD). Different from TN technology, the TFT display adopts "back-through" illumination mode-the hypothetical light source path is not from top to bottom like TN liquid crystal, but from bottom to top. In this way, a special light pipe is provided on the back of the liquid crystal, and the light source penetrates upward through the lower polarizing plate when the light source is irradiated. Because the electrodes on the upper and lower interlayers are changed to FET electrodes and common electrodes, the performance of liquid crystal molecules will also change when the FET electrodes are turned on. The display purpose can be achieved by shading and light transmission, and the response time is greatly increased to about 80ms. Because it has higher contrast and richer colors than TN-LCD, and the screen update frequency is faster, TFT is commonly known as "true color".
Compared with DSTN, the main feature of TFT-LCD is to configure a semiconductor switching device for each pixel. Because each pixel can be directly controlled by dot pulse. Therefore, each node is relatively independent and can be continuously controlled. This design method not only improves the response speed of the display screen, but also can accurately control the grayscale of the display, which is why the color of TFT is more realistic than DSTN. At present, most products of notebook computer manufacturers use TFT-LCD.
The early TFT-LCD was mainly used in the manufacture of notebook computers. Although TFT had a great advantage over DSTN at the time, due to technical reasons, TFT-LCD still had a big gap with traditional CRT displays in response time, brightness and viewing angle. Coupled with the extremely low production rate leading to its high price, making desktop-type TFT-LCD has become an unattainable stunner. However, with the continuous development of technology, the yield rate continues to increase, and the emergence of some new technologies has made TFT-LCD have made great progress in response time, contrast, brightness, and viewing angle, which has brought it closer to traditional CRT monitor gap. Nowadays, the response time of most mainstream LCD monitors is increased to below 50ms, which paves the way for LCD to become mainstream.
The application market of LCD should be said to have great potential. But in terms of LCD panel production capacity, LCDs in the world are mainly concentrated in three major production bases in Taiwan, South Korea and Japan. Asia is the center of LCD panel R&D and manufacturing, and the development of the three major production areas in Taiwan, Japan and South Korea is different.
