Sensing method of optical touch

A sensing method of optical touch, adapted for providing and sensing a sensing beam through at least one optical sensing module, wherein the sensing beam travels through a touch sensing area and is reflected back to the optical sensing module by a reflector, and the sensing beam reflected by different positions of the reflector enters different sensing pixel zones of the optical sensing module in an incident angle range, the sensing method of optical touch comprising:

• selecting a plurality of sensing pixel zones on the optical sensing module and choosing a main incident angle in the incident angle range according to a light intensity distribution sensed by each of the selected sensing pixel zones, wherein the sensing beam that enters the optical sensing module at the main incident angle has a maximum light intensity;
• and
• calculating main incident angles corresponding to unselected sensing pixel zones according to the main incident angles corresponding to the selected sensing pixel zones.