06320176 is referenced by 421 patents and cites 33 patents.

A vehicular rain sensor which senses precipitation at a vehicle window. The rain sensor comprises an imaging array sensor and a control. The imaging array sensor is directed at the vehicle window from inside the vehicle and comprises a camera device capable of imaging precipitation at a surface of the window. The camera is operable to image the precipitation at least in response to ambient light present at the window. The control responds to an output of the imaging array sensor in order to indicate precipitation at the surface of the window. The control determines the presence of precipitation via spatial filtering of the image received by the camera device.

Title
Vehicle rain sensor using imaging sensor
Application Number
9/599979
Publication Number
6320176 (B1)
Application Date
June 22, 2000
Publication Date
November 20, 2001
Inventor
Keith J Vadas
Coopersville
MI, US
Mark L Larson
Grand Haven
MI, US
Kenneth Schofield
Holland
MI, US
Agent
Van Dyke Gardner Linn & Burkhart
US
Assignee
Donnelly Corporation
MI, US
IPC
B60S 1/08
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