Patent ID: 8692804

Claim:
An optical touch system, comprising: a substrate; a glass module merely disposed in a non-active region at one side of the substrate; two light sources respectively disposed at two terminals of the glass module; three reflective clothes disposed on the edges of the substrate contiguously, wherein a touch region is formed among the three reflective clothes and the glass module and used for reflecting the light emitted from the two light sources; first and second image sensors disposed respectively next to the two light sources for capturing images in the touch region; and a processing module for determining whether a touch action is performed according to the images in the touch region; wherein the first and second image sensors capture first and second initial images respectively from the touch region and further combine the first and second initial images to obtain a background image, and the processing module performs an initial processing on the background image to determine a left boundary and a right boundary of the background image, and the processing module obtains an effective region according to the left boundary and the right boundary on the background image; wherein the first and second image sensors capture a current image from the touch region, and the processing module, based on the non-zero pixels on the left boundary and the right boundary, defines a window-of-interest region image of the current image and further compares the window-of-interest region image with a golden image to determine whether the glass module is strain offset.