| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a miniaturizable optical water drop sensor having excellent detection accuracy of a water drop and a high degree of freedom of an optical design. <P>SOLUTION: This optical water drop sensor equipped with a light emitting element 1, a light receiving element 2 and a light guide 3 is stuck on the car inside surface of windshield glass 4 by an adhesive member layer 5. The light guide 3 is provided with a light incoming surface 7 and a light outgoing surface 8 constituted respectively by a projecting optional curved surface, a light incoming/outgoing surface 9 constituted by a flat surface, and a reflecting surface 12 constituted of a metal film. Light emitted from the light emitting element 1 is introduced into the light guide 3 after light distribution is optimized by the light incoming surface 7, reaches the car outside surface 14 of the windshield glass 4 by being reflected by the reflecting surface 12 of the metal film 11, and totally-reflected and returned light reaches the light outgoing surface 8, and is emitted to the outside of the light guide 3 after light distribution is optimized by the light outgoing surface 8, and then condensed onto the light receiving surface of the light receiving element. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
