IMAGING RAIN SENSOR ILLUMINATION POSITIONING SYSTEM

摘要

A method and assembly for sensing moisture on the exterior surface of a sheet of glass (14) comprising the steps of emitting light rays from an illuminator (12) on an illuminator axis (I) intersecting the glass (14) at an illuminator angle of incidence Iθto reflect the light rays on a reflection axis (R) at an angle (Rθ) of reflection to the glass (14) and capturing on an imaging axis (C) the reflected light rays including reflections of moisture (19) on the exterior surface of the glass (14). The method is characterized by isolating the reflection of moisture (19) from the direct reflection of the illuminator (12) to prevent the capture of the direct reflection of the illuminator (12). This can be accomplished by offsetting the imaging axis (C) from the reflection axis (R), or by stopping the direct reflection of the illuminator (12) from being captured, as with a beam stop (24).