Faraday fiber-optic magnetic field sensor

The configuration of a fiber-optic magnetic field sensor of the distributed type was investigated. A planar configuration of the sensitive element overcame the principal shortcomings of a cylindrical distribution of the fiber in a sensor: it made it possible to tune the sensitive element to a selected wavelength of light and to increase the fiber length. A study of the temperature stability of the sensor indicated that it was sufficiently stable at room and higher temperatures. However, at low temperatures the influence of an external plastic cladding of the fiber waveguide was observed. An experimental prototype of a sensor with a sensitivity of ~ 5 X 10^–2 Oe was constructed and studied.