Sensor unit for rain sensor used for detecting e.g. rain drops in windscreen of motor vehicle, has optical fiber with light coupling area for deflecting light ray bundle to reflection surface that deflects bundle to coupling surface

摘要

The sensor unit has a light source (5) for emitting light ray bundles (L1-L3), and a photodetector for receiving the bundles. An optical fiber (4) has a light coupling area (20) for coupling one of the bundles (L1) to the fiber. The fiber is optically coupled to a coupling surface by a carrier element and directly deflects the coupled bundle to the coupling surface. The fiber has another light coupling area (21) for deflecting another light ray bundle (L2) to a reflection surface (22). The reflection surface deflects the latter bundle to the coupling surface.