Capacitive sensing in displacement type pointing devices

摘要

Systems and methods of capacitive sensing in displacement type point devices are described. In one aspect, a pointing device includes a sense electrode structure and a displaceable member. The sense electrode structure includes an arrangement of peripheral sense electrodes in a peripheral region surrounding a central sense electrode. The displaceable member is movable in an operational zone over the sense electrode structure. The displaceable member includes a target electrode facing the sense electrodes and overlapping at least a respective portion of the central sense electrode in each position of the displaceable member in the operational zone.