The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 11, 2001
Filed:
Jun. 26, 2000
Kazuhiko Matsuoka, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A scanning optical device to be used for an image forming apparatus such as a laser beam printer and a digital copying machine comprises a light source such as a semiconductor laser, an optical deflector such as a rotary polygon mirror, a first optical system for leading the light beam emitted from the light source to the optical deflector, and a second optical system for focussing the light beam deflected by the optical deflector onto a surface to be scanned. The first optical system is adapted to make the light beam strike a deflection surface of the optical deflector with a width greater than that of the deflection surface in the main-scanning direction. The second optical system has 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 the optical surface.