Patent ID: 9652081
Date: 2017-05-16
CPC Classifications: G06F

Claim:
1. An optical touch system for determining an action of at least one of a first object and a second object approaching or touching a base plane, the optical touch system comprising: a reflector disposed beside the base plane; at least one light source disposed beside the base plane and providing a detecting light, wherein the detecting light is transmitted to the reflector via a front of the base plane; at least one optical detecting sensor disposed beside the base plane, wherein the reflector reflects the detecting light and transmits the detecting light to a first optical detecting sensor via the front of the base plane; and a processor coupled to the optical detecting sensor, wherein when at least one of the first object and the second object approaches or touches the base plane, the processor determines a location of the base plane that is approached or touched according to a signal corresponding to the detecting light from the optical detecting sensor, and when the first object and the second object approach or touch the base plane, the processor determines which one of an intensity of a first portion of the signal corresponding to the first object and an intensity of a second portion of the signal corresponding to the second object is larger, wherein when a difference between the intensity of the first portion and the intensity of the second portion exceeds a predetermined extent, the processor determines a distance from a location that is approached or touched corresponding to a larger one of the intensity of the first portion and the intensity of the second portion to the optical detecting sensor is longer than a distance from a location that is approached or touched corresponding to a smaller one of the intensity of the first portion and the intensity of the second portion to the optical detecting sensor, wherein exceeding the predetermined extent is defined as a difference between a grey value of the intensity of the first portion and a grey value of the intensity of the second portion is larger than 1, wherein the at least one optical detecting sensor is a plurality of optical detecting sensors disposed at different locations beside the base plane, and when the first object and the second object approach or touch the base plane, the processor uses a triangulation to calculate a plurality of possible locations approached or touched by the first object and the second object according to the signals of the optical detecting sensors, wherein when the difference between the intensity of the first portion and the intensity of the second portion of each of the optical detecting sensors does not exceed the predetermined extent, the processor increases a length of exposure time of at least one the optical detecting sensors such that the difference between the intensity of the first portion and the intensity of the second portion corresponding to the at least one optical detecting sensor exceeds the predetermined extent, wherein the processor calculates a location of geometric center of the possible locations and decides a length of initial exposure time of at least one of the optical detecting sensors according to the location of geometric center.