Patent ID: 9471179
Filing Date: 2016-10-18
CPC Classification: G06F,H03M

Claim Text:
1. A laser optical touch control module disposed on one side of a display for providing optical positioning input function to form an optical touch control display contacted by a touch control widget comprising a light emitting part and a light receiving part; wherein a laser beam is emitted from a laser light source of the light emitting part and is reflected by a wide angle optical element so that a light fan of the reflected laser beam is larger than 90 degrees and a wide angle linear light beam is formed; the linear light beam is blocked to form a reflected laser beam when the touch control widget is in contact with surface of the display; the light receiving part receives and senses the reflected laser beam by a position sensor to output a signal and get a position of the touch control widget; wherein a light path of the light emitting part and a light path of the light receiving part share the same light path; thus the laser light source of the light emitting part and the position sensor of the light receiving part share the same wide angle optical element; the laser beam emitted from the laser light source and the reflected laser beam received and sensed by the position sensor pass the wide angle optical element; wherein a beam splitter is disposed on rear of the wide angle optical element so as to make the laser beam emitted from the laser light source pass through the beam splitter to be emitted to the wide angle optical element while the reflected laser beam passing through the wide angle optical element and entering the beam splitter is reflected to be received and sensed by the position sensor, wherein the beam splitter is a polarization beam splitter and a quarter-wave plate is arranged between the wide angle optical element and the polarization beam splitter; thus while the laser beam emitted from the laser light source passing through the polarization beam splitter, one polarization component of the laser beam passes through while the other polarization component perpendicular to the polarization component is reflected; wherein the polarization component passed the polarization beam splitter is converted into a left hand circular polarization or a right hand circular polarization by the quarter-wave plate; then the reflected laser beam is changed into the other circular polarization after being reflected by the touch control widget and is converted into the polarization component perpendicular to the original polarization component by the quarter-wave plate, and then entering the polarization beam splitter to be totally reflected onto the position sensor.