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. 27, 2007
Filed:
Feb. 14, 2005
Akihito Mori, Toride, JP;
Hajime Kaji, Abiko, JP;
Naoto Yamada, Kawasaki, JP;
Yoshitaka Yamazaki, Toride, JP;
Junichi Noguchi, Toride, JP;
Hajime Motoyama, Moriya, JP;
Satoshi Ogawara, Abiko, JP;
Yushi Oka, Abiko, JP;
Takayuki Kawakami, Nagoya, JP;
Akihito Mori, Toride, JP;
Hajime Kaji, Abiko, JP;
Naoto Yamada, Kawasaki, JP;
Yoshitaka Yamazaki, Toride, JP;
Junichi Noguchi, Toride, JP;
Hajime Motoyama, Moriya, JP;
Satoshi Ogawara, Abiko, JP;
Yushi Oka, Abiko, JP;
Takayuki Kawakami, Nagoya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
An image forming apparatus which is capable of eliminating density irregularities of an image formed caused by potential irregularities of the photosensitive member when the drum is irradiated by a beam of constant luminous intensity. A laser driver irradiates a beam modulated based on an image signal onto a photosensitive member. A current controller variably controls a driving current for driving the laser driver. A PWM pulse width converter modulates a pulse width of the beam based on the image signal. A potential sensor measures the potential of the photosensitive member after the photosensitive member is irradiated by a beam having a predetermined luminous intensity. A selector causes the current controller to correct the driving current based on low frequency components of irregularities of the potential and changes a modulation coefficient used for modulating the pulse width based on high frequency components of the irregularities of the potential.