SYSTEM AND METHOD FOR SENSING THE POSITION OF A POINTING OBJECT

摘要

A system for sensing the position of a pointer with respect to a reference frame is described wherein the system has a sensing device capable of measuring an electric field around the pointer when it is in proximity to the reference frame and a processing device capable of receiving signals regarding the measured electric field. The sensing device is also capable of taking measurements of the electric field from at least a first and second sensing location. The processing device designates the measurement of the electric field from the second sensing location as a reference value when the measurements of the electric field from the first and second sensing locations meet predetermined qualifications and calculates the position of the pointer on a first axis in the reference frame based on measurements of the electric field from the first and second sensing locations and said reference value.