Patent ID: 8773489

Claim:
An optical scanning apparatus for scanning a target surface using a plurality of light beams simultaneously along a first direction of the target surface, the optical scanning apparatus comprising: a light source having a plurality of light emitting elements to emit light beams; an optical deflector to deflect the plurality of light beams coming from the light source; an aperture member having an aperture disposed between the light source and the optical deflector; and a scanning optical system to guide the plurality of light beams deflected by the optical deflector to the target surface, the scanning optical system including a plurality of lenses, disposed after the optical deflector, a lens of the plurality of lenses having a strongest power in a second direction perpendicular to the first direction, wherein the plurality of light beams, corresponding to a plurality of scan lines on the target surface, deflected by the optical deflector intersect or contact each other at an optical face of the lens, and wherein a first conjugate point of light, emitted from the light source and passing an end portion in the long side direction of the lens, with respect to the aperture is set at a position on a path between the optical deflector and the optical face of the lens.