Multi-beam scanning system with sync signal generation based on single beam detection

摘要

An optical scanning unit receives beams from a plurality of beam light sources and directs the respective beams as a plurality of scanning beams with respect to the predetermined scanning range of the object to be scanned. A deflector receives one of the plurality of scanning beams by the optical scanning unit at a position near an end portion of the predetermined scanning range of the object to be scanned and deflects the received beam in a predetermined direction. A single beam detector detects the single scanning beam deflected in the predetermined direction by the deflector. A sync signal generating unit generates a sync signal on the basis of a detection output from the single beam detector. A control unit selectively generates control signals for driving the plurality of beam light sources in accordance with the sync signal from the sync signal generating unit, and while the single beam detector detects the single scanning beam, for driving only one of the plurality of beam light sources corresponding to the single scanning beam.