Tapered Fiber Bragg Grating Sensor Coated with Zinc Oxide Nanostructures for Humidity Measurement

A new approach to measure relative humidity changes by using fiber Bragg grating (FBG) is presented. Etching method is used to fabricate an FBG taper, which is then coated with zinc oxide (ZnO) nanostructures. The performance of the ZnO coated FBG is compared to its uncoated version and the experimental results produced a sensitivity of 2.51 pm/% and 1.36 pm/% respectively. The results demonstrate the ability of ZnO coatings in enhancing the performance of the sensor for the measurement of relative humidity.