Method and device for measuring surface defects, which produce scattered (stray) light, of optical media, such as glass or plastic, in particular of vehicle windows

摘要

The invention relates to a method and device for measuring surface defects, which produce scattered (stray) light, of optical media, such as glass or plastic, in particular of vehicle windows. According to the invention, it is proposed to direct HF-modulated radiation from a LED transmitter at an incidence angle of 50-70 DEG with respect to the incidence normal, on to the surface to be examined and, when a surface defect is present, scattered light occurring through diffuse reflection is detected using a photodetector and fed to an evaluation circuit. The device for carrying out the method consists of a transmitter/detector arrangement which can be guided at a constant distance over the surface to be examined, in which the detector (2) is located along the incidence normal of the transmission beam sent from the transmitter (1) under an incidence angle of 50-70 DEG on to the surface to be examined, and is provided with an evaluation circuit for outputting or displaying a detected scattered-light value. <IMAGE>