Patent ID: 7965278

Claim:
An optical navigation device comprising: a housing; an illumination system located within the housing and configured to illuminate a navigation surface; a plurality of height-specific imaging systems located within the housing, wherein the height-specific imaging systems are configured to generate image information in response to reflected light from the illumination of the navigation surface and wherein each one of the height-specific imaging systems is positioned to detect the largest portion of the reflected light at a different separation distance between the housing and the navigation surface; and a tracking engine configured to generate relative movement information, related to movement between the housing and the navigation surface, in response to the image information; wherein the tracking engine is configured to select image information from one of the height-specific imaging systems in response to a comparison of the image information from the plurality of height-specific imaging systems and to use the selected image information to generate the relative movement information; wherein the plurality of height-specific imaging systems comprises: a first height-specific focal lens configured to focus light that reflects off the navigation surface, wherein the first height-specific focal lens is positioned to receive the largest portion of reflected light at a first separation distance between the optical navigation device and the navigation surface, wherein the first separation distance is the distance when the optical navigation device sits directly on the navigation surface; and a plurality of additional height-specific focal lenses configured to focus light that reflects off the navigation surface, wherein the plurality of additional height-specific focal lenses are positioned to receive the largest portion of reflected light at a plurality of different separation distances between the optical navigation device and the navigation surface, wherein the plurality of different separation distances are greater than the first separation distance and different from each other.