Patent ID: 7053887
Filing Date: 2006-05-30
Classification: G06F

Abstract:
1. A method for indicating that a set of simultaneous contact points on a touch-sensitive screen contains a plurality of contact points, the method comprising: setting a multiple contact point discrimination threshold; at locations along a first edge of the touch-sensitive screen, sending probes across the touch-sensitive screen; at locations along a second edge of the touch-sensitive screen, attempting to detect probes sent across the touch-sensitive screen, the second edge being across the touch-sensitive screen from the first edge; of a set of locations along the second edge where attempts to detect probes fail to detect a probe or that detect a probe in an altered state, storing a first location in the set that is at least as close to a third edge of the touch-sensitive screen as any other location in the set, and storing a second location in the set that is at least as close to a fourth edge of the touch-sensitive screen as any other location in the set, the third and fourth edges each being adjacent to the first and second edges; comparing the multiple contact point discrimination threshold with a distance between the first and second locations; and if the distance between the first and second locations is greater than the multiple contact point discrimination threshold, then indicating that the set of simultaneous contact points contains a plurality of contact points.