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What Is The Principle Of Capacitive Pcap Touch Screen Overlay?

The capacitive pcap touch screen overlay is widely used for the friendly man-machine interface provided by people. It has low power consumption and long life. As well as the smooth operation performance, the capacitive touch screen has been sought after by the market. A variety of capacitive touch screen products have appeared one after another. As the process progresses and batches. Its cost continues to drop, gradually replacing resistive touch screens.

Capacitive screens need to achieve multi-touch. It depends on the electrodes that increase the mutual capacitance. Simply put, it is to divide the screen into blocks, and set up a group of mutual capacitance modules in each area to work independently. Therefore, the capacitive pcap touch screen overlay can independently detect the touch conditions of each area. After processing, simply realize multi-touch.

The Structure Of The Pcap Touch Screen Overlay

Capacitive technology touch panel CTP (Capacity Touch Panel) uses the current induction of the human body to work. The capacitive screen is a four-layer composite glass screen. Also the inner surface of the glass screen and the interlayer are each coated with a layer of ITO (Nano Indium Tin Metal Oxide). What's more, the outermost layer is a protective layer of silica glass with a thickness of only 0.0015mm. The sandwich ITO coating is used as the working surface. Four electrodes are drawn from the four corners. The inner layer of ITO is the screen layer to ensure the working environment.

The Working Principle Of The Pcap Touch Screen Overlay

When the user touches the capacitive screen. Due to the electric field of the human body, the user's finger and the work surface form a coupling capacitor. Because there have high-frequency signals connect to the working surface. So the finger absorbs a very small current. This current flows from the electrodes on the four corners of the screen. And theoretically, the current flowing through the four electrodes is proportional to the distance from the finger to the four corners. The controller obtains the position through precise calculation of the ratio of the four currents. It can reach 99% accuracy and has a response speed of less than 3ms.