Simulation and Fabrication of Tapered Fiber Optics Hydrogen Sensor

In this paper, we report simulation and fabrication of a gas sensor based on tapered fiber by measuring the output power in the presence of different hydrogen concentrations. The fibers were tapered to 15.5 μm and 26.6 μm by using oxy-butane torch and the output spectrum is obtained using a 1550nm laser source and an optical spectrum analyzer (OSA) and the sensitivities of the tapered fiber sensors were determined. It is shown that by increasing the percentage of the hydrogen in the surrounding environment, the output power is changed by 7% and 2.3% in the presence of 4% hydrogen for tapered fibers of diameter 15.5μm and 26.6 μm respectively. The response time of the aforementioned sensors were 13 and 17.6 seconds respectively. In addition, the repeatability tests of the fabricated sensors demonstrates acceptable results. Simulation of the tapered fiber sensors demonstrates good agreement with experimental results. The obtained sensitivity makes hydrogen detection below 4% easy and accurate.