Working Principle of TFT Screen

TFT is the abbreviation of "Thin Film Transistor", which generally refers to thin film liquid crystal display, but actually refers to thin film transistor (matrix) - it can "actively" control each independent pixel on the screen, which is the origin of the so-called active matrix TFT. So how is the image produced? The basic principle is very simple: the display screen is composed of many pixels that can emit light of any color. As long as each pixel is controlled to display the corresponding color, the purpose can be achieved. In TFT LCD, backlight technology is generally used. In order to accurately control the color and brightness of each pixel, a switch similar to a shutter needs to be installed behind each pixel. When the "shutter" is opened, light can pass through, and when the "shutter" is closed, light cannot pass through. Of course, the actual implementation in technology is not as simple as just said. LCD (Liquid Crystal Display) uses the characteristics of liquid crystal (liquid when heated, solid when cooled). Generally, liquid crystal has three forms:
・Layered liquid crystal similar to clay
・Filamentary liquid crystal similar to thin matchsticks
・Liquid crystal similar to cholesterol
LCD uses filaments. When the external environment changes, its molecular structure will also change, thus having different physical properties - it can achieve the purpose of letting light through or blocking light - that is, the blinds just mentioned. Everyone knows the three primary colors, so each pixel on the display needs to be composed of the three similar basic components introduced above, which control the three colors of red, green and blue respectively. The most commonly used is the twisted nematic TFT liquid crystal display.