Patent ID: 8314770

Claim:
A game controller, comprising: a housing with apertures provided therein to admit light from a light source, a pair of optical detectors respectively provided adjacent to the apertures, each optical detector having: a continuous light sensitive surface and surface resistivity, a pair of contacts provided on opposing edges of the light sensitive surface, and operational amplifiers coupled to the pair of contacts, and a controller for calculating a position of the light source according to the equations: X = ( S D 2 ) ⁢ ⁢ ( x L - x R x L + x R ) , where X is a lateral position of the light source, S D is a lateral distance between the optical detectors, x L is a lateral location of a light spot relative to a center of a first of the pair of optical detectors, and x R is a lateral location of a light spot relative to a center of a second of the pair of optical detectors, and Z = ( f x L - x R ) ⁢ ( S D ) , where Z is a separation distance between the light source and the optical detectors and f is a focal length of the aperture.