Patent ID: 9366565
Filing Date: 2016-06-14
CPC Classification: G01J,G02B,G06F

Claim Text:
1. A light out-coupling arrangement for a touch sensitive system, wherein the touch sensitive system comprises a light guide of a material with a refractive index n g and a top surface configured to be exposed to ambient light, and a bottom surface, the touch sensitive system further has an in-coupling arrangement comprising at least one emitter arranged along the periphery of the light guide and is configured to emit light into the light guide whereby the light propagates in the light guide via total internal reflection, TIR, wherein the out-coupling arrangement comprises at least one detector arranged along the periphery of the light guide and configured to receive the light propagating in the light guide; an optical filter provided between the light guide and the at least one detector, wherein the optical filter has a first side and a second side where the first side is arranged to face the at least one detector, and the second side is arranged to receive light from the light guide, the optical filter is further made of a medium with a refractive index n