Optical element for lidar system - forms extremely short length cassegrain telescope with laser emitter combined in rugged housing

摘要

The optical element (10) is made of glass or plastics material similar to glass and has a rear mirrored surface (10a) with a recess for a receiving diode (12) which is adjustable by means of the correcting foot (14) formed by an interference filter (14) cemented to the diode cover glass (12a). The filter (14) also carries a baffle (15) for gathering stray light, which the optically active surface (12b) of the diode (12) also does at the same time. The form of the optical element is such that the light paths are always of the same length and almost completely independent of the angle of incident and the distance to the optical axis. The diode (12) is connected to the electronic circuits (13) by connectors (12c) and feeds a laser diode mounted beneath the lens, thus forming a Lidar system which can be made small and rugged and shockproof as well as impervious to surroundings.