Three-Dimensional-Printed Fabrication of POFs Using Different Filaments and Their Characterization for Sensing Applications

This paper presents the development and sensor applications of 3D-printed polymer optical fibers (POFs) using commercially available filaments. The well-known intensity variation sensor was developed using this fiber for temperature and curvature sensing, where the results indicate a linear response in the curvature analysis, with a coefficient of determination (R [Formula: see text]) of 0.97 and sensitivity of 4.407 × 10 [Formula: see text] mW/ [Formula: see text] , whereas the temperature response was fitted to an R [Formula: see text] of 0.956 with a sensitivity of 5.718 × 10 [Formula: see text] mW/ [Formula: see text] C. Then, the POF was used in the development of a modal interferometer by splicing the POF in-between two single-mode fibers (SMFs), which result in a single-mode-multimode-single-mode (SMS) configuration. The such interferometer was tested for temperature and axial strain responses, where the temperature response presented a linear trend R [Formula: see text] of around 0.98 with a sensitivity of −78.8 pm/ [Formula: see text] C. The negative value of the sensitivity is related to the negative thermo-optic coefficient commonly obtained in POFs. Furthermore, the strain response of the SMS interferometer showed a high sensitivity (9.5 pm/ [Formula: see text]) with a quadratic behavior in which the R [Formula: see text] of around 0.99 was obtained. Therefore, the proposed approach is a low-cost, environmentally friendly and straightforward method for the production of highly sensitive optical fiber sensors.