Patent ID: 7193608

Claim:
A system for collaborating between a plurality of users, each user having a laser input device for interacting with an initial image, said system having: a controller for controlling operation of said laser input devices and registering interactions by said users via said laser input devices, each of said laser input devices operated by said controller to transmit a modulated laser beam having a distinct transmission pattern, each said distinct transmission pattern being produced by turning a respective one of said laser beams on and off according to a respective cycle, said laser beam producing a laser spot on said initial image; an initial image provider for providing said initial image on a display; a camera for capturing successive images to form a sequence of captured images for processing and mapping said successive images to said initial image, each of said successive images having a plurality of picture elements; and a processor for analyzing said successive images to determine the presence of said laser spots, wherein respective laser spots turn on and off such that they appear in certain ones of said successive images in accordance with said distinct transmission pattern; whereby said processor determines a relationship between each pixel in each said successive image and the corresponding pixel on said initial image, and determines interactions on said display associated with said laser input devices such that laser spots of each of said input devices are uniquely identified based on said distinct transmission patterns.