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:
Jun. 11, 2013
Filed:
Sep. 24, 2010
Applicants:
Robert Wueest, Zurich, CH;
Andreas Frank, Zurich, CH;
Klaus Bohnert, Oberrohrdorf, CH;
Inventors:
Assignee:
ABB Research Ltd, Zurich, CH;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R 31/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A fiber optic current or magnetic field sensor uses a sensing fiber in a coil for measuring a current or a magnetic field and has a retarder for converting between linearly polarized light and elliptically polarized light. The retardation of the retarder, its temperature dependence as well as its azimuth angle in respect to the plane of the fiber coil are optimized in dependence of the birefringence in the sensing fiber in order to minimize the influence of temperature variations and manufacturing tolerances on the overall scale factor of the sensor.