LOW-COST SYSTEM TO DETERMINATE THE X-Y POSITION IN A RESISTIVE TOUCH-SCREEN

摘要

In this paper a novel low-cost system to determinate the x-y position in a resistive touch-screen is presented. The x-y position and the touch-point resistance are measured by using simple interface electronics. The system is mainly composed by three parts: the resistive touch-screen, a signal-processing circuit and a microcontroller. The system does not need an A/D converter. A three-signal auto-calibration technique is used to eliminate the effects of unknown offset and unknown gain in the system. The resolution of the low-cost system amounts to 0.2 mm for a measurement time of 30 ms.