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. 12, 1989
Filed:
Feb. 24, 1988
Muneo Tokita, Yokohama, JP;
Niro Nagata, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A laser printer includes a semiconductor laser for generating a laser beam which is modulated according to information, a rotating polygon mirror for scanning the laser beam generated by the semiconductor laser, and an f.theta. lens system for imaging, onto a photosensitive drum, the laser beam scanned by the rotating polygon mirror. The f.theta. lens system has first and second lenses arranged, in this order, next to the rotating polygon mirror and on the optical path through which the laser beam is introduced from the rotating polygon mirror to the photosensitive drum. Each of the first and second lenses has light-entering and -emerging faces which are formed in a non-spherical shape.