Patent ID: 8072441
Filing Date: 2011-12-06
Classification: G06F

Abstract:
1. A method for detecting a touch screen, the touch screen including a first conductive layer and a second conductive layer, each conductive layer having a positive terminal and a negative terminal, the method comprising: coupling the positive terminal of the second conductive layer to a positive reference voltage, coupling the negative terminal of the second conductive layer to a negative reference voltage, sampling the positive terminal of the first conductive layer to obtain a series of first voltage samples V coupling the positive terminal of the first conductive layer to the positive reference voltage, coupling the negative terminal of the first conductive layer to the negative reference voltage, sampling the positive terminal of the second conductive layer to obtain a series of third voltage samples V calculating a rotating parameter X(i) according to the first voltage samples V determining a rotating direction of two touch points in the touch screen according to the rotating parameter X(i), wherein the rotating parameter X(i) is a function of Xplate is a total resistance of the first conductive layer, and Yplate is a total resistance of the second conductive layer.