Investigation of metal-coated optical fiber in temperature response using TD-BOCDA

In this study, we analyzed the change in Brillouin frequency according to the temperature of metal-coated optical fibers installed in a distributed optical fiber sensor. We used aluminum coated optical fibers for the analysis. The existence of hysteresis was confirmed between the Brillouin frequency changes during the heating and cooling of the metal-coated optical fiber. The Brillouin frequency of the metal-coated optical fiber exhibited a rapid change at an initial 30 °C temperature change region; however, the changes remained constant thereafter. Therefore, the obtained results confirm that metal-coated optical fibers can be used as distributed fiber-optic sensors without hysteresis under continuous heating or cooling conditions.