Patent ID: 6633424
Filing Date: 2003-10-14
Classification: G02B

Abstract:
An optical scanning device comprising:a light source; a deflecting surface configured to deflect a light beam output from said light source; focusing optics configured to focus the light beam deflected by said deflecting surface on a subject surface to be scanned; and at least one reflecting member intervening between said deflecting surface and the subject surface, wherein the light beam incident to said deflecting surface and an optical axis of said focusing optics are angularly spaced from each other in a plane of polarization, wherein when a section in a subscanning direction is seen from a side where the light beam is incident to said deflecting surface, an inclination of said at least one reflecting member relative to a plane perpendicular to said light beam is positive when clockwise and is referred to by &THgr;, wherein a function f(i) is f(i)=1 when i is an even number or f(i)=âˆ’1 when i is an odd number, wherein a direction of polarization of the light beam just after emission from said light source is inclined by an angle of &thgr; relative to a main scanning direction, wherein when a clockwise direction as seen from a rear of said light source is positive, the angle &thgr; lies in a range of: 0Â°or âˆ’45Â°â€ƒwherein when said condition 1 holds, said at least one reflecting member is an â€œnâ€  reflecting member, as counted from said light source in a direction of propagation of the light beam, except for said deflecting surface and satisfies a relation of f(n)Ã—&THgr;>0, and wherein when said condition 2 holds, said at least one reflecting member is an â€œnâ€  reflecting member, as counted from said light source in said direction, except for said deflecting surface and satisfies a relation of f(n)Ã—&THgr;<0.