Patent ID: 9322952
Filing Date: 2016-04-26
CPC Classification: B60S,G01N,G01W

Claim Text:
1. A method for detecting rain on a windshield, comprising: detecting vibrations on the windshield, caused by rain, with a piezoelectric sensor, the vibrations being detected via at least one wiper blade of a windshield wiper system, and via a coupling between the at least one wiper blade and the windshield, determining a sensor value from the output of the piezoelectric sensor, which depends on the degree of wetting or raindrops hitting the windshield, comparing the sensor value with known vibration profiles, and determining the environmental condition on the windshield, caused by the rain, from said comparing; wherein at least one additional sensor value is detected, wherein an optical signal is sent out, the optical signal is reflected on the windshield in a predetermined detection range, the reflected optical signal is detected, and a differential value is derived from the transmitted and detected signal, based upon which the degree of wetting is determined for the windshield.