OPTICAL SCANNING APPARATUS UTILIZING A RE-ENTRANT LASER BEAM

摘要

In the synchronous scanning display device disclosed, the laser active medium and means for mode-locking multiple-mode laser oscillations are disposed in a resonator adapted to provide a folded optical path yielding a large plurality of resolvable spots at a reflector of stepped transmissity and reflectivity. The intensity of the output from the resonator at each spot is selectively controlled by a video signal applied to a broad area modulator disposed just outside the stepped-reflectivity reflector. Typically, an isolator is employed to produce unidirectional propagation of the laser radiation along the folded path.