Abstract: The device for visibility measurement is designed primarily for use in motor vehicles. A light emitter is arranged inside the driver's compartment preferably on the rear view mirror in front of the windshield. The light emitter generates light pulses or flashes radiating through the windshield. The light scattered back due to soiling on the inside and outside of the windshield or in scatter zones, formed by fog or smoke or the like, in front of the windshield, impinges a light sensor, preferably likewise arranged on the rear view mirror inside the driver's compartment. By utilizing light pulses of various wavelengths and processing of the output signals of the light sensor in predetermined or predeterminable time windows or intervals, not only the respective visibility but also the type of viewing impairment can be determined.