Patent ID: 8797296

Claim:
A method for adjusting brightness of an optical touch panel, wherein said optical touch panel comprises a microprocessor, a display module including a back light source in one of a plurality of operation modes, and an optical position detection device including optical transmitting devices and optical receiving devices, and wherein said plurality of operation modes comprise an automatic calibration mode, said method comprising: detecting, via said optical receiving devices, a current ambient light level on said display module; generating, via said optical receiving devices, a current ambient light level signal indicative of said current ambient light level and transmitting said current ambient light level signal to said microprocessor; and adjusting, via said microprocessor, brightness of said back light source based on said current ambient light level signal, wherein, when said back light source is in said automatic calibration mode, said adjusting comprises automatically calibrating said brightness of said back light source based on a predefined relation between said current ambient light level and said brightness of said back light source in response to a change in said current ambient light level.