What is touch screen calibration?

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The touch screen is usually closely bound to the display screen. Taking a mobile phone screen with a touch as an example, the touch screen is at the top and the display is at the bottom. The so-called touch screen calibration is to obtain the X of the touch, the Y-direction coordinates are correctly mapped to the display position through the calibration coefficient.

Specifically, after you click the touch screen, you will get a coordinate value of X and Y (this is the physical coordinate value on the touch screen ), but this coordinate does not overlap with the corresponding coordinate values on the display screen. How can we overlap the two coordinates? We need to use a calibration coefficient to overlap the two coordinate values, this is why the touch screen must be calibrated before it can be used properly.

The calibration method includes two-point calibration, three-point calibration, and five-point calibration. The purpose is to calculate the calibration coefficient by reading the coordinate values of several points and save the calculated coefficients, after you click the touch screen coordinates obtained by the touch screen, and then pass the calibration coefficient, the coincidence coordinates on the display screen will be obtained.