Patent ID: 7688455
Filing Date: 2010-03-30
Classification: G06F

Abstract:
1. A method for detecting the coordinates of multiple positions on an infrared touch screen of a touch panel including a plurality of X-axis infrared emitting and receiving elements and a plurality of Y-axis infrared emitting and receiving elements, embodied on an apparatus, the method comprising: measuring and storing a maximum received optical level of a pair of infrared emitting and receiving elements, infrared emission and reception of which is not impeded by any object, and initializing an index variable used to identify multiple touched spots determining that the touch screen has been touched when a received optical level of a pair of infrared emitting and receiving elements, infrared emission and reception of which is impeded by an object, is less than the maximum received optical level measuring a minimum received optical level of the pair of infrared emitting and receiving elements to detect center coordinates of the object; and reading an index variable for the center coordinates and determining that the center coordinates are new and setting an index variable for the center coordinates if no index variable is read for the center coordinates and storing the center coordinates and the index variable for the center coordinates; and determining that the center coordinates are continuous, if a spot corresponding to the stored center coordinates with the index variable set for the center coordinates has been moved at a movement speed less than a preset movement speed limit, and storing center coordinates of the spot after the movement, replacing the stored center coordinates, for the index variable.