To understand how it works, you first have to look at the structure: In front of a TFT display there is a glass plate that is coated with a conductive material. In front of it are tiny spacers that create a space between another conductive coating and the inner conductive layer. The outer conductive coating is protected by a scratch-resistant cover plate. With the help of a control device, a voltage gradient in the x direction is generated in the inner conductive layer. A voltage gradient is built up in the y-direction in the outer conductive layer. If the two conductive layers are pressed together by strong contact, the control electronics determine the coordinates. Conclusion: you can look at a touch screen as if it were a simple mouse. However, you can also use the touchscreen displays.
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