Patent ID: 7738007

Claim:
An optical scanning device that scans a scan target surface with a light beam in a main scanning direction, the optical scanning device comprising: a light source that includes a plurality of light emitting elements arranged in a two-dimensional array; a pre-deflector optical system arranged along a first light path of the light beam emitted from the light source; a deflector that deflects the light beam that has passed through the pre-deflector optical system; and a scanning optical system that focuses the light beam deflected by the deflector onto the scan target surface, wherein the pre-deflector optical system includes a first optical element that has a positive power and a second optical element that has a negative power, and the light beam emitted from the light source is incident on the first optical element, and the second optical element is arranged along a second light path of the light beam from the first optical element to the deflector, and the first and second optical elements are set at positions at which an error of a lateral magnification in a direction corresponding to a sub scanning direction of an optical system including the pre-deflector optical system and the scanning optical system is reduced, and an absolute value of power of the first optical element is larger than an absolute value of power of the second optical element.