For the convenience of operation, people use touch screen instead of mouse or keyboard. To work, we must first touch the touch screen mounted on the front of the display with a finger or other object, and then the system will locate and select information input according to the icon or menu position touched by the finger. The touch screen is composed of a touch detection component and a touch screen controller. The touch detection component is installed in front of the display screen for detecting the user's touch position and receiving the touch screen controller after delivery; The main function of the touch screen controller is to receive touch information from the touch point detection device, and convert it into contact coordinates, and then send to the CPU, it can receive the COMMAND from the CPU and execute it.