US Patent 7348586 Exterior element sensor

An exterior element sensor can include an optical element mounted on a window. The optical element can include a cylindrical lens having both ends shaped spherically and a central portion that exerts little or no influence on exterior element detection (such as rain, snow, ice, water, liquid, debris, or other materials) when visible light transmits therethrough. In addition, infrared or other light can be used to detect exterior elements located on the window. A black filter can be employed, if desired, which blocks visible light and transmits infrared light therethrough to separate visible light from infrared light, thereby allowing the exterior element sensor to be used together with an exterior light sensor without losing accuracy.