CAPACITIVE RAIN SENSOR

摘要

Methods and apparatus for making and sensing a liquid substance such as liquid water. Also, apparatus and methods for sensing the change of phase of a substance. In one embodiment, a fringe-effect capacitor is placed proximate to a surface for which it is desirable to sense the presence of liquid water, such as a windshield. The presence of rain on the surface of the windshield changes the electrical flux between electrodes of the capacitor. This change is sensed, and used for other purposes, such as turning on windshield wipers. Also, apparatus and methods for a fringe-effect capacitor.