Highly sensitive temperature measurement based on polymer-coated single-mode, multimode, single-mode, fiber structure

摘要

We propose a way to enhance the temperature sensitivity of single-mode-multimode-single-mode (SMS) fiber structure, by replacing the cladding of silica multimode fiber with a polymer coating. Based on the mode expansion method, we analyze transmission characteristics of the polymer-coated SMS fiber structure and optimize design parameters for sensing. Then we do experiments and verify theoretical analysis. By using the optimized parameters in sample fabrication, a temperature sensor is obtained with an easily detected and demodulated transmission spectrum; and then by monitoring valley wavelength shifts, a measuring sensitivity of about 706 pm/°C is achieved.