Magneto-optic current sensor using a highly-linear birefringent optical fibre

Current sensing utilising a highly-linear birefringence (HiBi) fibre has been investigated. The research is aimed at developing a practical device which will be free from the noise caused by the environmental disturbances. The principle of the sensor is based on the resonance nature of Faraday coupling in HiBi fibre, where constructive coupling between the eigenmodes of the fibre only occurs when the magnetic field is periodic with a period equal, to close, to the fibre beat length. The characteristics of the Faraday coupling in a HiBi optical fibre and its use as in a current sensor is presented