Patent ID: 6084696
Filing Date: 2000-07-04
Classification: G02B,G03F

Abstract:
A scanning optical system for emitting a scanning beam onto a surface to be scanned, comprising:a laser source that emits a laser beam;a deflector that deflects said laser beam emitted by said laser source to scan withing a predetermined scanning area;an f.theta. lens to which said laser beam deflected by said deflector is incident, said laser beam passing through said f.theta. lens scans on said surface to be scanned, said f.theta. lens including at least one lens which cancels an uneven intensity distribution characteristic of said scanning optical system within an area where said laser beam scans on said surface to be scanned;wherein said at least one lens has a gradient transmission ratio, said gradient transmission ratio being determined based on an inversion of said uneven intensity distribution characteristic of said scanning optical system; andwherein said at least one lens is formed of material having a predetermined unit transmission ratio, said gradient transmission ratio of said at least one lens depending on a shape of said at least one lens.