Patent ID: 7812822

Claim:
An opto-mechanical pointing device, comprising: a housing comprising an upper portion and a base; two rollers partially enclosed within the housing and partially extending beyond the base such that the two rollers are in contact with a surface, wherein one roller is operable to move in a first direction and the other roller is operable to move in a second direction that is orthogonal to the first direction; and one or more optical modules each comprising a light source operable to emit light and a detector operable to detect an amount of reflected light, wherein the amount of reflected light detected by each detector determines a speed and a distance for at least one roller as the opto-mechanical pointing device moves over the surface, wherein the two rollers comprise a first roller having a first shape and a second roller having a second shape that is different from the first shape so that an angle between a plane of the base and a plane of the surface varies as the opto-mechanical pointing device is moved over the surface.