Types Of Touch Screen Displays

    According to the medium used and the working principle, the above touch screen can be divided into four types: resistance type, capacitance induction type, infrared type and surface acoustic wave type. The touch screen is gradually upgraded and developed from low-grade to high-grade: from resistive, infrared to capacitive and surface acoustic wave.
    A capacitive touch screen uses a transparent metal layer coated on a glass plate as a conductive material. There are narrow electrodes on the four sides of the touch screen, forming a low voltage AC electric field inside the conductive material. When a finger touches a metal layer and a conductive object touches it, the capacitance of the contact will be changed, and the current emitted by the four electrodes will flow to the contact. The controller can determine the position information of the touch through the current. Due to the variation of capacitance with temperature, humidity, or grounding conditions, its stability is poor and often leads to drift.