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. 06, 2010
Filed:
Oct. 22, 2008
Applicants:
Klaus Bohnert, Oberrohrdorf, CH;
Andreas Frank, Zurich, CH;
Hubert Brandle, Oberengstringen, CH;
Inventors:
Assignee:
ABB Research Ltd., , CH;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R 31/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
The current in a conductor is measured by exploiting the Faraday effect in a sensing fiber. The light returning from the sensing fiber is split into at least two parts, at least one of which is analyzed by a first circular analyzer for generating a first signal. A second part may e.g. be analyzed by a second circular analyzer, and a third part may be analyzed by a linear analyzer. By combining the signals obtained in this way, the current induced phase delay in the returning light can be measured efficiently and accurately.