US Patent 7133178 Image forming apparatus and image forming method

A printer has a laser emitter for emitting a laser beam to irradiate a surface of a photosensitive member; a reflector for reflecting the laser beam to a target position on the photosensitive member; a driver for moving the reflector; a resolution changeover designation acceptor for accepting a designation on a low resolution or a high resolution as a resolution for image formation; and an emission controller for controlling the laser emitter to emit the laser beam along a scanning line in a forward direction or a scanning line in a backward direction defined by the movement of the reflector driven by the reflective mirror driver if the designated resolution is the low resolution, and for controlling the laser emitter to emit the laser beam along the scanning line in the forward direction and the scanning line in the backward direction if the designated resolution is the high resolution.