OPTICAL SCANNING DEVICE AND IMAGE FORMING APPARATUS

摘要

An optical scanning device includes plural light sources, a light deflector including a deflecting-reflecting surface, and a scanning optical system including plural folding mirrors and plural scanning lenses, wherein the plural scanning lenses have the same shape, at least one of an optical surface at the incidence side and an optical surface at the emission side has an asymmetric shape with respect to a sub-scanning direction, and has an asymmetric shape in the sub-scanning direction with respect to the main scanning direction, and a difference in a number of folding mirrors disposed between the corresponding scanning lens and the light deflector between light incident on the light deflector from a direction inclined to one side relative to a virtual surface including a normal line of the deflecting-reflecting surface and light incident on the light deflector from a direction inclined to the other side is an odd number.

主权项

1. An optical scanning device that individually scans a plurality of surfaces to be scanned with a plurality of lights in a main scanning direction, the optical scanning device comprising:
a plurality of light sources, each of which corresponds to each of the plurality of surfaces to be scanned; a light deflector which includes at least one deflecting-reflecting surface, and on which a plurality of lights emitted from the plurality of light sources is incident from a direction inclined relative to a virtual plane that includes a normal line of the deflecting-reflecting surface and is orthogonal to the deflecting-reflecting surface; and a scanning optical system including a plurality of folding mirrors and a plurality of scanning lenses, each of the plurality of scanning lenses corresponding to each of the plurality of surfaces to be scanned, the scanning optical system guiding each of the plurality of lights deflected by the light deflector to each of the plurality of surfaces to be scanned, wherein the plurality of scanning lenses has the same shape, at least one of an optical surface at the incidence side and an optical surface at the emission side has an asymmetric shape with respect to a sub-scanning direction orthogonal to the main scanning direction, and has an asymmetric shape in the sub-scanning direction with respect to the main scanning direction, and a difference in a number of folding mirrors disposed between the corresponding scanning lens and the light deflector between light incident on the light deflector from a direction inclined to one side relative to the virtual plane and light incident on the light deflector from a direction inclined to the other side is an odd number.