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:
Apr. 29, 2003
Filed:
Apr. 13, 2001
Teruaki Mitsuya, Ibaraki, JP;
Nobuyoshi Hoshi, Ibaraki, JP;
Hisao Okada, Ibaraki, JP;
Yoshihiko Sano, Ibaraki, JP;
Shinichi Akatsu, Ibaraki, JP;
Shinya Kobayashi, Ibaraki, JP;
Hitachi Koki Co., Ltd., Tokyo, JP;
Abstract
In an electrophotographic apparatus, regions having at least three different potential levels Vc, Vw, and Vr are formed on a photosensitive member by using an exposing device, and developing processes respectively using colored particles of different kinds are performed by normal development and reversal development on two potential levels Vc and Vr excluding the intermediate potential level Vw. The apparatus has an auxiliary exposing unit for forming a fringe development preventing potential in an edge of an image forming region in order to prevent fringe development from occurring. The auxiliary exposing unit sets an auxiliary exposure amount by performing pulse-width modulation on a laser driver.