Patent ID: 8259063

Claim:
An input method of a pointer input system, said pointer input system comprising a data processing system, an image projecting system, a projection screen and a photosensing system, said input method comprising steps of: performing a setting procedure and a correcting procedure on said pointer input system to obtain a space conversion relationship and an over-bright position; inputting at least a light spot onto said projection screen; arranging at least a dual-band filter or a multi-band filter between said photosensing system and said projecting screen to filter off monochromic or poly chromic light captured by the photosensing system; capturing said light spot by said photosensing system, thereby obtaining a light-spot image; recognizing at least a relevant light spot of said light-spot image comprising the steps of: excluding said over-bright position from the light-spot image, and checking whether said light-spot image complies with a light-spot characteristic situation, thereby obtaining at least a light-spot data; and converting said at least a light-spot data into at least an input data of said data processing system according to said space conversion relationship.