Patent ID: 7609249
Filing Date: 2009-10-27
Classification: G06F

Abstract:
1. A system for generating position information, the system comprising: a reflector; an image collection system configured to generate a first set of image data and a second set of image data, wherein the first set of image data includes a stronger indication of the reflector than the second set of image data; and a processor configured to use the first set of image data and the second set of image data to generate position information related to the reflector, wherein the processor is configured to take the difference between the first set of image data and the second set of image data; wherein the reflector is a retroreflector that is integrated into a pointing device; wherein taking the difference between the first set of image data and the second set of image data comprises taking the difference between corresponding data points of the first and second sets of image data such that most of the corresponding data points from the first and second sets of image data cancel each other out except for data points that correspond to the retroreflector.