Accession Number : ADD011941

Title :   Triaxial Optical Fiber System for Measuring Magnetic Fields.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Bobb,L C

Report Date : 22 May 1984

Pagination or Media Count : 7

Abstract : This patent discloses an optical system wherein light is transmitted through fiber-optic members orthogonally configured in a triaxial arrangement for measuring the magnetic field vector preset in the environment. In one preferred embodiment, a set of three fiber-optic coils positioned coaxially along respective orthogonal axes and having predetermined lengths and diameters are coupled to a source of polarized light for transmitting the light subject to Faraday rotation of its plane of polarization. In another preferred embodiment, light, not necessarily polarized, is transmitted along respective orthogonal axes through a set of three bifurcated fiber-optic cables each formed having a reference branch on which a magnetostrictive material is intimately connected to produce optical path length changes related to the magnetic field component along the respective axes. Photodetectors are used in both embodiments to produce current signals indicative of characteristic changes in the transmitted light, and the current signals are digitally processed to provide magnitude and directional information regarding the magnetic field vector.

Descriptors :   *PATENTS, *MAGNETIC DETECTORS, *OPTICAL EQUIPMENT, *FIBER OPTICS TRANSMISSION LINES, *MAGNETOSTRICTION, MAGNETIC FIELDS, POLARIZATION, FARADAY EFFECT, COILS, ORTHOGONALITY, PHOTODETECTORS

Subject Categories : Magnetic & Electric Fld Detection & Detectors
      Electricity and Magnetism
      Fiber Optics and Integrated Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE