Patent ID: 6288734
Filing Date: 2001-09-11
Classification: B41J,G02B

Abstract:
A scanning optical device comprising:a light source;an optical deflector having a deflection surface adapted to deflect the light beam emitted from said light source in the main-scanning direction;a first optical system for leading the light beam emitted from said light source to said optical deflector, said first optical system being adapted to make the light beam strike the deflection surface of the optical deflector with a width greater than that of the deflection surface in the main-scanning direction; anda second optical system for focussing the light beam deflected by said optical deflector onto a surface to be scanned;said second optical system having an optical element provided on at least an optical surface thereof with an anti-reflection film having a film thickness so adapted as to maximize its light transmittance for the angle of incidence of the most off-axis ray of the light beam deflected by the optical deflector and striking said optical surface.