Patent ID: 7006269

Claim:
A multi-beam scanning device, comprising: a multi-beam light source unit that emits a plurality of light beams having different wavelengths, the plurality of light beams being aligned in a main scanning direction; a first polygonal mirror that deflects the plurality of light beams emitted by the multi-beam light source in the main scanning direction; an fθ optical system, the plurality of light beams deflected by said first polygonal mirror to scan at a substantially constant speed; a second polygonal mirror that deflects the plurality of light beams passed through said fθ optical system in an auxiliary scanning direction that is perpendicular to the main scanning direction, said second polygonal mirror deflects the plurality of light beams in the auxiliary direction by one line at each main scanning of the plurality of light beams; a projecting optical system that projects the plurality of light beams deflected by said second polygonal mirror on a screen.