Optoelectronic sensor device for detecting wetting of automobile windscreen

摘要

The sensor device uses a parallel light beam directed onto the inside of the windscreen (4) for total internal reflection by the outer surface of the windscreen, with detection of the reflected beam via a photodetector (19). The reflected parallel beam received from the windscreen is directed onto the photodetector via a parabolic reflector (13), providing a convergent beam, positioned in the path of the reflected beam so that the intensity of the light received by the photodetector is higher when the outside of the windscreen is wet.