A light pointer is selectively activated to direct a light beam onto an interactive display surface, forming a pattern of light that is detected by a light sensor disposed within an interactive display table. The waveband of the light produced by the light pointer is selected to correspond to a waveband...http://www.google.com/patents/US7499027?utm_source=gb-gplus-sharePatent US7499027 - Using a light pointer for input on an interactive display surface
