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:
Mar. 11, 1997
Filed:
Dec. 18, 1992
Kyu Takada, Suwa, JP;
Seigo Epson Corporation, Tokyo-to, JP;
Abstract
An image forming apparatus including an image bearing member, a charging unit, a laser beam scanning apparatus and a developing unit. The laser beam scanning apparatus includes a semiconductor laser array for emitting laser beams, a collimator lens for collimating the beams, a rotating polygon mirror for deflecting the beams collimated by the lens, and an aperture stop between the laser array and the mirror. The following relations between the aforementioned elements of the apparatus are satisfied: ##EQU1## where f is a focal length of the collimator lens; s is a distance between a focal point on a mirror side of the collimator lens and the aperture stop; t is a distance between one of the light emitting portions that is spaced farthest, relative to others of the light emitting portions, from the optical axis; D is a diameter of the aperture stop, and d is a diameter of each of the laser beams collimated by the collimator lens.