US Patent 7411712 Optical scanner and image formation apparatus

An optical scanner has light source units spaced from each other along a first direction and having optical axes parallel to each other. Positions from which the light beams are emitted are spaced from each other by a predetermined distance at least along a predetermined direction. The optical scanner also includes a deflection unit that deflects the light beams together and scans the light beams along a second direction perpendicular to the first direction. The optical scanner also has imaging units that form an image with each of the light beams on a surface and a housing unit that holds the light source units, the deflection units, and the imaging units.