Patent ID: 8183518

Claim:
A driving circuit of a photosensing touch panel comprising: a first photodiode coupled between a first voltage source and a sensing node and for generating a first current in accordance with a brightness of an external incident light and a heat of a finger; a second photodiode coupled between the sensing node and a second voltage source and for generating a second current in accordance with the heat of the finger, the second photodiode being shielded from the external incident light; an amplifier circuit for detecting the brightness of the external incident light regardless of the heat of the finger by subtracting the second current from the first current at the sensing node, and a switch coupled between the amplifier circuit and an output line and for selectively supplying a third current generated according to the brightness of the external incident light, regardless of the heat of the finger, to a data output line in accordance with a scan signal applied to the switch.