Study of measuring temperature for a Fabry–Pérot interferometer-based fiber-tip sensor

Optical sensors play a crucial role in many fields today, and their use is becoming increasingly attractive. This is mainly due to their unique properties, which make them more technologically advanced than conventional electrical sensors. Sensors based on IP-Dip polymer in the form of a Fabry–Pérot interferometer (FPI), manufactured using direct laser writing (DLW) lithography and placed on the facet of an optical fiber, are the next step in development. This paper presents information on the analyses and modeling of an FPI using various numerical methods, namely the transfer matrix method (TMM), rigorous coupled-wave analysis (RCWA), and finite-difference time-domain (FDTD). It also covers a test facility for investigating issues related to the effect of temperature changes on the spectral range and phase shift. The results of temperature characterization were analyzed using methods devised during the simulation analyses. The results were subsequently compared to the simulated models to describe the underlying physical phenomena resulting in the observed spectral shifts.