Opto-mechanical scanner for satellite observation - uses oscillating planar mirrors with optical transmitter and receiver for synchronising mirrors

摘要

The optical-mechanical sweep system for an observation satellite has two planar mirrors (93, 94) which oscillate in opposite senses through an angle (B) of 4 deg. -5 deg to sweep received image of the earth. The mirror pivot axes are parallel with the satellite vector speed. A system for synchronising the mirros (93, 94) has a light source (91) which transmits a focussed beam of light which is reflected by the planar mirrors and a fixed mirror (95) to a receiver (96) comprising an avalanche diode covered by a screen (98). The focussed beam sweeps through an angle (8B) and two synchronising systems delineate a line sweep.