Patent attributes
An optical scan apparatus which deflects a plurality of light beams to scan a write region on a scan surface in a main scan direction is configured to include a light source which has a plurality of emission portions emitting the plurality of light beams arranged two-dimensionally on a plane in parallel to the main scan direction and a sub scan direction perpendicular to the main scan direction; a deflector which deflects the plurality of light beams from the plurality of emission portions; a light receiving element which receives the light beams and outputs a synchronous detection signal in accordance with the received light beams; and a control unit which selectively controls any one of the emission portions to emit a light beam upon each scanning and allows the light beam from the selected emission portion to be incident on the light receiving element via the deflector.
