Patent Document ID: 4481450
Application ID: 06480127
Patent Status: 1

Claim One:
1. A control system for a motor vehicle having a windshield, comprising: first means mounted on the inner surface of said windshield at one end of a section thereof for emitting a beam of radiation into said windshield at an angle in the range between the critical angles of said windshield with respect to air and water to a normal to the windshield inner surface so that the beam totally internally reflects off the outer surface of the windshield in the absence of water on the windshield outer surface and partially reflects off said outer surface in the presence of water on the windshield outer surface; second means mounted on the windshield inner surface at the other end of said section for detecting and converting said reflected beam into a first signal; third means for comparing said first signal with a reference value to generate a second signal indicative of the presence of said water sufficient to warrant that a window of said vehicle be closed; and fourth means, responsive to said second signal, for closing said window.