Patent ID: 6999208
Filing Date: 2006-02-14
Classification: G02B

Abstract:
1. An optical scanning system comprising: a light source; and an optical scanner which performs optical scanning of a surface to be scanned by deflecting a luminous flux having a wavelength λ from said light source by means of an optical deflector, and condensing the deflected flux toward the surface to be scanned through a scanning image forming optical system, thereby forming an optical spot on said surface to be scanned, wherein said scanning image forming optical system has at least one lens; and wherein, in the said scanning image forming optical system, when a focal length fσ in a main scanning direction at a surface accuracy σi is defined as:  where, fm represents a focal length in the main scanning direction of said scanning image forming optical system; k represents the number of lens surfaces; ω represents an aimed spot diameter of the optical spot in the main scanning direction at an image height of 0; σi represents a surface accuracy of an i-th lens surface as counted from an optical deflector side; n represents a refractive index of material of a lens having the i-th lens surface; and 1/L represents a spatial frequency in the main scanning direction on said lens surface; then, said surface accuracy σi, said focal length fσ, said refractive index n, and said spatial frequency 1/L satisfy, for each lens surface, a following condition: