Polymer Comparison on Temperature Sensors Based on Fiber-Optic Fabry-Perot Interferometer

We compare the behavior of three temperature sensors based on fiber optic Fabry-Perot interferometers (FPI). The length of the cavities were 30 ± 2 µm and they were filled with polydimethylsiloxane (PDMS), poly(methyl methacrylate) (PMMA), and the optical adhesive NOA61. The sensitivities for each sensor were 2.20 nm/°C, 0.42 nm/°C, and 0.57 nm/°C, respectively. The refractive index (RI) sensitivity showed by these devices was caused by an integrated consequence of the thermo-optical and expansion coefficients.