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:
Jan. 26, 1993
Filed:
Jul. 10, 1991
Takashi Nakazawa, Ibaraki, JP;
Minoru Ohshima, Ibaraki, JP;
Masami Ishikawa, Ibaraki, JP;
Tsukasa Ogawa, Ibaraki, JP;
Tohru Miyasaka, Ibaraki, JP;
Takao Umeda, Ibaraki, JP;
Hitachi Koki Co., Ltd., Tokyo, JP;
Hitachi Ltd., Tokyo, JP;
Abstract
A device for measuring a surface potential at a photosensitive body including: a potential sensor for measuring surface potentials at a plurality of positions on the photosensitive body; a plurality of sample hold circuits; and an adder for adding each measured surface potential held in each sample hold circuit, or an adder which adds up each measured surface potential and average the sum. The addition or averaging of the measured values serves to eliminate eccentricity-induced errors and noise in the surface potential measurements, thereby allowing a correct surface potential to be obtained.