Patent ID: 7250940
Filing Date: 2007-07-31
Classification: G06F

Abstract:
1. A method of operating a resistive touch sensitive screen for increased security and lower power consumption, the resistive touch screen comprising a first conductive layer and a second conductive layer, the first conductive layer having a first electrode and a second electrode, the second conductive layer having a first electrode and a second electrode, the method comprising the steps of: applying substantially equal voltages to the first and second electrodes of the first conductive layer; applying substantially equal voltages to the first and second electrodes of the second conductive layer such that approximately zero current is conducted in the first and second conductive layers under quiescent conditions; measuring currents from the first and second electrodes of the first conductive layer; measuring currents from the first and second electrodes of the second conductive layer; adding the currents from the first and second electrodes of the first and second conductive layers together; and sending an alert signal when the currents from the first and second electrodes of the first and second conductive layers added together do not equal approximately zero.