The working principle of the resistive touch screen is mainly through the pressure sensing principle to achieve the operation and control of the screen content. This type of touch screen screen part is a multilayer composite film that is very compatible with the display surface, in which the first layer is glass or organic glass. The bottom layer, the second layer is a barrier layer, the third layer is a multiple resin surface layer, the surface is also coated with a transparent conductive layer, and is covered with a layer of plastic layer with a hardened outer surface and a smooth scratch-resistant surface. The conductive layer and glass layer sensor on the surface of the multi-layer grease surface is divided by many tiny compartments and the current passes through the surface layer. When the surface layer is pressed down, it touches the bottom layer. The controller reads out the appropriate current from the four corners at the same time. Calculate the distance of the finger position. The touch screen utilizes two highly transparent conductive layers to form a touch screen with a distance of only 2.5 microns between the two layers. When the finger touches the screen, the two conductive layers that are usually insulated from each other have a contact at the touch point, because one of the conductive layers turns on the 5V uniform voltage field in the Y-axis direction, so that the voltage of the detection layer changes from zero to zero. Non-zero, after the controller detects this connection and performs A/D conversion and compares the obtained voltage value with 5V, the Y-axis coordinate of the touch point can be obtained and the X-axis coordinate can be obtained similarly. It is the common basic principle of all resistance technology touch screens.