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:
May. 12, 1981
Filed:
Oct. 31, 1978
Applicant:
Inventors:
Koji Suzuki, Yokohama, JP;
Takehiko Shibata, Kokubunji, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
324458 ;
Abstract
A surface potentiometer having a measuring electrode disposed at a predetermined distance from a surface to be measured and in which the electric field between the measuring electrode and the surface to be measured is intermittently shielded by a rotatable chopper to thereby induce an AC signal in the measuring electrode and the AC signal is clamped at a timing corresponding to the position of the chopper relative to the electrode to thereby accurately measure the potential of the surface to be measured.