In TN and STN type liquid crystal displays, the method of driving electrodes is to drive by the cross method of X and Y axes, as shown in Figure 2. Therefore, if the display part is larger and larger, the reaction time of the electrode in the center may be longer. In order to make the screen display consistent, the overall speed will be slower. To put it simply, it is like the screen update frequency of the CRT display is not fast enough, then the user will feel the screen flickering and jumping; or when fast 3D animation display is required, but the display speed of the display cannot keep up, the displayed result may be delayed. Therefore, early liquid crystal displays have certain limitations in size and are not suitable for watching movies or playing 3D games.
In order to improve this situation, later liquid crystal display technology adopted active-matrix addressing to drive, which is currently the ideal device for achieving high data density liquid crystal display effects, and the resolution is extremely high. The method is to use silicon transistor electrodes made of thin film technology and use scanning to select the opening and closing of any display point (pixel). This is actually using the nonlinear function of thin film transistors to replace the nonlinear function of liquid crystals that is difficult to control. As shown in Figure 2, in a TFT type liquid crystal display, a small grid-like line is drawn on the conductive glass, and the electrode is a matrix switch composed of thin film transistors. There is a control box at the intersection of each line. Although the drive signal quickly scans through each display point, only the selected display point in the transistor matrix on the electrode receives a voltage sufficient to drive the liquid crystal molecules, causing the liquid crystal molecular axis to turn to form a "bright" contrast. The unselected display points are naturally "dark" contrast, thus avoiding the display function from relying on the electric field effect of the liquid crystal.