Accession Number : ADD009810

Title :   Fiber Optic Magnetic Field Sensor.

Descriptive Note : Patent Application,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Taylor,Henry F

Report Date : 09 Aug 1982

Pagination or Media Count : 27

Abstract : An optical fiber magnetometer uses a birefringment optical fiber in combination with a magnetostrictive block for inducing strains in the fiber in response to an applied magnetic field to thereby cause a change in the degree of briefringence of the fiber. This change in birefringence is measured by directing the light exiting the fiber through a conversion element such as a polarizer or a prism and then detecting the resulting intensity modulation in a photodetector. A variety of inventive features are set out in this disclosure, including the use of spliced fibers with a 90 degree axis rotation to compensate for environmental effects, the use of twisted fiber for gradient field sensing, and the rotation of the sensor fiber to eliminate low-frequency noise and to obtain a vector field and field gradient sensing capability.

Descriptors :   *Patent applications, *Magnetometers, *Fiber optics, Magnetic fields, Gradients, Birefringence, Intensity, Modulation, Photodetectors, Inventions

Subject Categories : Test Facilities, Equipment and Methods
      Electricity and Magnetism
      Fiber Optics and Integrated Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE