The interior of capacitive touch screen consists of driving electrode and receiving electrode. The driving electrode sends out low-voltage and high-frequency signals and projects them to the receiving electrode to form a stable current. When the human body touches the capacitive screen, because the human body is grounded, the finger and the capacitive screen form an equivalent capacitance.High-frequency signals can flow into the ground through this equivalent capacitor, so the amount of charge received by the receiving end is reduced. When the finger is close to the emitting end, the charge drops more obviously. Finally, the contact point is determined according to the current intensity received by the receiving end. As for multi-touch, simply put, the screen is divided into blocks. Each group of mutual capacitance modules in each area works independently, and the capacitive screen can independently detect the touch situation in each area, and multi-touch can be realized after processing.Touch Screen ctp (Capacitive Touch Screen) uses a current sensor from the human body. Capacitance screen is a four-layer composite glass screen. The inner surface and intermediate layer of the glass screen are coated with ito (nano indium tin oxide) respectively. The outer layer is 0.0015 mm thick Shi Ying glass protective layer, the middle layer is coated with ito working surface, four electrodes are formed at four corners, and the inner layer is a shielding layer to ensure the working environment.When the user touches the capacitive screen, due to the electric field, the user's finger forms a coupling capacitance with the working surface. Because there are high-frequency signals on the working surface, the finger absorbs very little current and flows out from the electrodes at the four corners of the screen. The current flowing through the four electrodes is theoretically proportional to the distance from the finger to the four corners. The response speed is less than 3ms, and the accuracy can reach 99%.