Patent ID: 10496227

Abstract:
An embodiment of the invention provides a touch sensing apparatus, comprising: a light transmissive element (10) that defines a touch surface; a set of emitters (30a) arranged around the periphery of the touch surface to emit beams of light into the light transmissive element, wherein a first portion of the beams (50) of light propagate inside the light transmissive element while illuminating the touch surface such that an object touching the touch surface causes an attenuation of the propagating light, and wherein a second portion of the beams (90) of light pass out of the light transmissive element and are reflected to travel above the touch surface, a set of light detectors (30b) arranged around the periphery of the touch surface to receive light from the set of emitters from the transmissive element and from above the touch surface, wherein each light detector is arranged to receive light from more than one emitter.