Characterization study of Optical Fiber Refractive Index Sensor Based on Fabry-Perot Interferometer

Abstract

In this work, an optical fiber refractive index sensor based on the Fabry-Perot interferometer technique is submitted. Single-mode fibers with different diameters (125, 60, and 50) μm were used. The chemical etching technique is used to reduce the fiber diameters. The sensor heads were immersed into liquids of different refractive indices. Two types of liquids were tested, salty and sugary liquids with different refractive indices. From the obtained results all the sensors have a high linearity and good wavelength and intensity sensitivity. For all tested sensors, the wavelength sensitivity was higher for sensors immersed in salty liquids. The sensitivity is 34338 pm/RIU for sensors with a diameter of 50 μm. The response of changing the intensity is also observed the higher intensity sensitivity is 1116.859 μW/RIU for sensors with a diameter of 125 μm immersed into sugary liquids.