RAIN SENSOR WITH SIGMA DELTA MODULATION AND / OR FOOTPRINT COMPARISON (DE)

摘要

A system and/or method for sensing the presence of moisture (e.g., rain) on a window such as a vehicle window (e.g., vehicle windshield, sunroof or backlite). At least one sensing capacitor (C1, C2, C3, C4) is supported by a window such as a vehicle windshield, the capacitor (s) having a field that is affected by moisture (e.g., rain) on a surface of the window. A sensing circuit outputs an analog signal that is based on and/or related to the capacitance (s) of the sensing capacitor (s). The analog output of the circuit is converted to a digital signal, and subjected to processing (e.g., correlation) for determining whether moisture (e.g., rain, dew, fog, etc.) or the like is present on the surface of the window.