Patent ID: 7760186
Filing Date: 2010-07-20
Classification: G06F

Abstract:
1. A pointing device comprising: an illumination system that illuminates a portion of a surface over which said pointing device travels with coherent light; an imaging system comprising a first window for receiving light from said illuminated portion of said surface and transmitting that light to a first imaging array such that a speckle pattern is generated on said first imaging array and a second window comprising an imaging optical system for forming an image of part of said illuminated portion of said surface on a second imaging array; and a controller that selects either the first imaging array without any imaging lens, or said second imaging array with an imaging lens, and compares the output of said selected imaging array at first and second times to determine a displacement indicative of the direction and distance said positioning device moved between said first and second times, wherein said first window of said imaging system is situated on a path for said light between said illuminated portion of said surface and said first imaging array, said imaging system not including any imaging lens on said path to provide said path that lacks said imaging lens so that said speckle pattern is not destroyed.