Patent ID: 8223417

Claim:
An optical scanning device comprising: a light source; a pre-deflector optical system that is arranged in an optical path of a light flux emitted from the light source and includes at least one diffractive optical element; a deflector that deflects the light flux passing through the pre-deflector optical system; and a scanning optical system that focuses the light flux deflected by the deflector on a surface to be scanned, wherein the diffractive optical element is obtained by joining a resin layer to a glass-lens base material, a diffractive surface of the diffractive optical element has a multi-step structure including a plurality of zonal surfaces substantially perpendicular to an optical axis and a plurality of step surfaces, and the diffractive surface is formed in the resin layer, wherein a junction between the glass-lens base material and the resin layer is formed into a flat shape, and wherein the diffractive surface has no power at room temperature.