Optical fiber temperature sensor based on Fabry-Perot interferometer with photopolymer material

Abstract

We propose and demonstrate a new method for fabricating a Fabry-Perot interferometer sensor. This work uses photopolymerizable materials to construct Fabry-Perot interference structures, making the fabrication process more straightforward and less expensive than other methods. We put a 532 nm laser into the single-mode fiber (SMF) to fabricate photopolymer probes on the face of the fiber. The end face of the probe and the end face of the SMF will form a Fabry-Perot interferometer (FPI). At the same time, to demonstrate its ability to be easily fabricated for sensing various parameters, we incorporated PDMS into the photopolymer material and conducted temperature sensing experiments. The relationship between the concentration of the PDMS and the temperature sensitivity is studied. The experimental results show that the higher the concentration of PDMS, the higher the temperature sensitivity. In the case of ensuring other capabilities, the sensitivity has reached − 1.18 nm/°C in the temperature range of 20–110 °C. We propose and demonstrate a new method for fabricating a Fabry-Perot interferometer sensor. This work uses photopolymerizable materials to construct Fabry-Perot interference structures, making the fabrication process more straightforward and less expensive than other methods. We put a 532 nm laser into the single-mode fiber (SMF) to fabricate photopolymer probes on the face of the fiber. The end face of the probe and the end face of the SMF will form a Fabry-Perot interferometer (FPI). At the same time, to demonstrate its ability to be easily fabricated for sensing various parameters, we incorporated PDMS into the photopolymer material and conducted temperature sensing experiments. The relationship between the concentration of the PDMS and the testing sensitivity is studied. The experimental results show that the higher the concentration of PDMS, the higher the testing sensitivity. In the case of ensuring other capabilities, the sensitivity has reached − 1.20507 nm/°C in the temperature range of 20–80 °C. • This work uses a free-radical photopolymerizable formulation is sensitive between 450 and 550 nm and converted through a free-radical cross-linking polymerization under green light irradiation, which can easily fabricate waveguide structure on the fiber end face. • This photopolymeriazble formulation allows us to add different sensitive materials for the purpose of making different sensors. • We add PDMS into the photopolymeriazble formulation to measure the temperature. In the temperature range of 20–80 °C, the sensitivity reached − 1.20507 nm/°C and demonstrates good stability.