Influence of Optical Fiber Coatings on the Long-term Accuracy of Interferometric Fiber-optic Current Sensors

We conducted accelerated ageing tests of different types of acrylate-coated elliptical-core polarization maintaining fibers that are used in fiber-optic current sensors. In particular, we determined how exposure to elevated temperatures affects the polarization extinction ratio of the fibers and, as a consequence, the sensor scale factor. The results show that the proper choice of the fiber coating is imperative for maintaining the sensor's long-term accuracy and reliability.