Patent ID: 8525863

Claim:
An optical scanning device comprising: an enclosure having a plurality of windows covered with transparent members; a plurality of light sources housed in the enclosure; a scanning portion for deflecting each of a plurality of light beams emitted from the plurality of light sources at a constant angular speed in a main scanning direction; optical elements constituting respective light paths from the scanning portion to the windows for the plurality of light beams, respectively; a light amount attenuation portion for attenuating light amount in a light path of a first light source among the plurality of light sources in a downstream side of a position where a light beam emitted from a second light source enters as stray light; and a drive portion for driving the first light source so as to compensate for light amount attenuated by the light amount attenuation portion, wherein the light amount attenuation portion is a transparent optical element that attenuates light transmittance in a downstream side of a position where the stray light enters in a light path of the first light source.