Patent ID: 6154303
Filing Date: 2000-11-28
Classification: G02B

Abstract:
A laser scanning system comprising:a light source for emitting a light-modulated beam from a laser diode;a collimator lens for forming the beam emitted from said light source into parallel beams;a slit for allowing the parallel beams having passed through said collimator lens to partially pass therethrough;a cylinder lens for converging said parallel beams having passed through said slit in a sub scan direction;a polygonal rotating mirror rotated at high speed for allowing the parallel beams from said cylinder lens to deflect at a prescribed angle; anda scanning lens system for receiving the parallel beams after being deflected by said polygonal rotating mirror to form an image on a scanned surface by converging the parallel beams in scan and sub scan directions, said scanning lens system comprising a first scanning lens and a second scanning lens made of a plastic substance wherein a first surface of said first scanning lens is a spherical surface, a second surface of said first scanning lens and third and fourth surfaces of said second scanning lens are formed of an aspherical toric surface having a rotating axis in said scan direction.