Fiber Optic Magnetic Field Sensor.
DEPARTMENT OF THE NAVY WASHINGTON DC
Pagination or Media Count:
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.
- Test Facilities, Equipment and Methods
- Electricity and Magnetism
- Fiber Optics and Integrated Optics