| 摘要 |
Disclosed is an optical fibre birefringence compensation mirror which as well as being easy to align and assemble, compensates for the birefringence generated by a sensor optical fibre, particularly in current sensors, increases the vibration resistance of a current sensor, and enables large current detection by a current sensor. Also disclosed is a current sensor wherein vibration resistance has been increased due to the optical connection of the optical fibre birefringence compensation mirror. The optical fibre birefringence compensation mirror comprises: an optical fibre, a birefringence element, a lens, a magnet, a Faraday rotator, and a mirror. From the light incidence/emission end surface of the optical fibre, the birefringence element, Faraday rotator, and mirror are arranged in said order, and the optical fibre is a single mode type optical fibre. Light comes in from the optical fibre, and is separated into two linearly polarised lights by the birefringence element. The polarisation planes of the two linearly polarised lights are rotated by 45 degrees by the Faraday rotator, and the two linearly polarised lights are point-symmetrically reflected at one point by the mirror, then once again rotated by 45 degrees by the Faraday rotator, then re-combined to be one light by the birefringence element and made to enter the optical fibre. |
