Patent ID: 6744545
Filing Date: 2004-06-01
Classification: B41J,G02B,Y10S

Abstract:
An optical scanning lens which is used in a scanning and image forming optical system which gathers a light flux deflected by a light deflector in the vicinity of a surface to be scanned,wherein: said lens is formed by a resin having the following properties: photoelasticity constant&lE;8 (10âˆ’13 cm2/dyne); saturation moisture absorption=0.5 (%); and mold shrinkage coefficient=0.7 (%), and the following condition is satisfied: 0n(x)âˆ’min[&Dgr;n(x)]|<34Ã—10âˆ’5â€ƒâ€ƒ(A) â€ƒwherein: &Dgr;n(x) denotes a refractive-index distribution existing inside said lens, in a range which the light flux passes through, in said lens; and min[&Dgr;n(x)] denotes the minimum value of said &Dgr;n(x).