Patent ID: 7548230

Claim:
A system for providing a positional input value to an electronic device, the system comprising: a sender portion adapted to be manipulated by a user to specify a target point within a target area, the sender portion including a light projecting system adapted to project a beam of light including a predefined spatially varying characteristic at the target area; a receiver portion including at least one sensor unit, the at least one sensor unit adapted to measure at least one value of the spatially varying characteristic of the beam of light at the location of the at least one sensor unit, wherein the receiver portion includes logic adapted to determine a positional input value associated with the target point from the at least one value of the predefined spatially varying characteristic at the location of the at least one sensor unit; wherein the predefined spatially varying characteristic of the beam of light is a pattern including a plurality of intensity transitions; and wherein the positional input value is a measure of relative motion of the target point, and the receiver portion includes logic to determine a magnitude of the relative motion of the target point by detecting a change in the presence of at least one of the intensity transitions at the location of the at least one sensor unit.