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Title: Micro-position sensor using faraday effect

A micro-position sensor and sensing system using the Faraday Effect. The sensor uses a permanent magnet to provide a magnetic field, and a magneto-optic material positioned in the magnetic field for rotating the plane of polarization of polarized light transmitted through the magneto-optic material. The magnet is independently movable relative to the magneto-optic material so as to rotate the plane of polarization of the polarized light as a function of the relative position of the magnet. In this manner, the position of the magnet relative to the magneto-optic material may be determined from the rotated polarized light. The sensing system also includes a light source, such as a laser or LED, for producing polarized light, and an optical fiber which is connected to the light source and to the magneto-optic material at a sensing end of the optical fiber. Processing electronics, such as a polarimeter, are also provided for determining the Faraday rotation of the plane of polarization of the back-reflected polarized light to determine the position of the magnet relative to the sensing end of the optical fiber.
Authors:
 [1] ;  [2] ;  [3] ;  [4]
  1. (Livermore, CA)
  2. (Pittsburgh, PA)
  3. (Tracy, CA)
  4. (Brentwood, CA)
Publication Date:
OSTI Identifier:
902642
Report Number(s):
7,183,765
US patent application 10/879,222
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Patent
Research Org:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA
Sponsoring Org:
United States Department of Energy
Country of Publication:
United States
Language:
English