Magnetic field detector

摘要

There is provided a system (100) for magnetic field detection, comprising a fiber optic interrogator (104) adapted to interrogate a first length of optical fiber (102) with interrogating radiation, detect radiation backscattered from said optical fiber and analyze said detected radiation to provide distributed sensing indicative of mechanical disturbances of said optical, wherein the optic fiber is mechanically coupled to a material whose dimensions vary dependent on applied magnetic field. Changes in dimensions of the optic fiber as can be detected by virtue of changes in back-scattering of light from said fiber using the principles of fiber optic distributed acoustic sensing.

主权项

1. An apparatus for magnetic field detection, comprising:
a first length of optical fibre; a second length of optical fibre deployed alongside the first length of optical fibre; a fibre optic interrogator configured to interrogate said first length of optical fibre with interrogating radiation, detect radiation backscattered from said first length of optical fibre and analyse said detected radiation to provide a first distributed sensing signal indicative of mechanical disturbances of said first length of optical fibre and to interrogate said second length of optical fibre with interrogating radiation, detect radiation backscattered from said second length of optical fibre and analyse said detected radiation to provide a second distributed sensing signal indicative of mechanical disturbances of said second length of optical fibre; wherein the said first length of optical fibre is mechanically coupled to a magnetically responsive material whose dimensions vary dependent on the applied magnetic field; andwherein said second length of optical fibre is configured to be substantially insensitive to any changes in applied magnetic field.