Patent ID: 6894767
Filing Date: 2005-05-17
Classification: G01C,G01S,G02B

Abstract:
1. A light wave distance-measuring system, comprising a projection optical system having an optical axis of outgoing light and for projecting a measuring light, and a photodetection optical system having an optical axis of a returning light and for receiving a reflection light, wherein said photodetection optical system comprises a light receiving lens for receiving and for converging the reflection light, a light receiving surface where the reflection light enters, and a ring-like perforated optical member arranged between said light receiving surface and said light receiving lens and having an aperture, wherein said aperture transmits the reflection light converged by said light receiving lens in case of distance measurement at long distances, and said perforated optical member has multiple focal points for converging the reflection light to said light receiving surface corresponding to a range of near distance in case of distance measurement at near distances.