Current Sensor Based on a Fiber Bragg Grating Coated by Electroplated Magnetostrictive Material

A current sensor based on a ferromagnetic-coated fiber Bragg grating (FBG) embedded in a small dimension coil has been presented and experimentally validated. A 5 mm-long FBG has been coated with a Ni thin film by means of sputtering and electrodeposition methods. The measurements and results reported show that a simple and cost-effective metal-coated FBG can be successfully applied as DC-current sensor. The designed sensor measures DC current up to 10 A with a sensitivity of 2,5 pm/A and a linearity error of 3%.