High-sensitivity quasi-distributed temperature sensors based on weak FBGs Fabry-Perot structure with metal coating

摘要

This letter puts forward weak FBGs Fabry-Perot (FP) structures with copper coating for quasi-distributed temperature measurement. The weak FBGs (-33dB) are fabricated by on-line draw tower. The sensors system exhibits the superiorities of high signal to noise ratio (SNR). At the same time, wavelength/frequency/time multiplexing immensely increases the capacity of the sensing system. In the experiment, the sensors show the high temperature sensitivity, reaching to 24.68 pm/°C because of the sensors deposited metal film. The results imply the feasibility of high-sensitivity quasi-distributed temperature measurement.