Optical scanning device and image forming apparatus

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.