US Patent 7728861 Optical device

A laser beam source that emits a laser beam includes a reflecting unit that has a plurality of reflecting members and reflects the laser beam emitted from the laser beam source, a deflecting and scanning unit that deflects and scans with the laser beam reflected by the reflecting means, and an adjusting unit that moves at least part of the reflecting members, and adjusts the size of the laser beam entering the deflecting and scanning unit.