Patent ID: 6509995
Filing Date: 2003-01-21
Classification: G02B

Abstract:
An optical scanning device comprising:a light source emitting a light flux; a coupling optical system coupling the light flux from said light source to a subsequent optical system by transforming the light flux into one of a parallel light flux, an approximately convergent light flux, and an approximately divergent light flux; a light deflector reflecting the light flux from said coupling optical system with a deflection reflective surface, and deflecting the light flux; a scanning and imaging optical system condensing the deflected light flux from said light deflector onto a surface to be scanned as a beam spot; and a correcting optical system, disposed between said coupling optical system and the deflection reflective surface, for performing a self correcting shift of focal position of the beam spot on said surface to be scanned, wherein said correcting optical system comprises at least one pair of lenses comprising a resin-made lens having an anamorphic surface with a negative power in each of a main scanning direction and a sub-scanning direction, and a glass-made lens having an anamorphic surface with a positive power in at least the sub-scanning direction.