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:
Oct. 08, 2002
Filed:
Jun. 06, 2001
Naoji Moriya, Nara, JP;
Masahiro Ihara, Kyoto, JP;
Shimadzu Corporation, Kyoto, JP;
Abstract
Light with a plane of polarization rotated during transmission is converted to parallel light by a collimating lens. The parallel light is transmitted through a first birefringent plate to be separated into two polarized rays orthogonal to each other regardless of the rotation of the plane of polarization. The two polarized rays have planes of polarization rotated by the strength of a magnetic field in the course of transmission through a Faraday element. The polarized rays are reflected by a mirror at a downstream stage, each ray returning along the same optical path and transmitted through the birefringent plate again. At this time, the polarized rays are separated into four polarized rays with different ratios of light intensity according to the rotation of the planes of polarization. From these rays, the collimating lens selects only two orthogonal polarized rays to be detected. The selected rays are detected by a photodetector at a downstream stage. An arithmetic operation is carried out based on the two light intensities, thereby measuring the magnetic field with high sensitivity.