An Optical Fiber Fabry–Perot Pressure Sensor With Optimized Manufacturing Parameters

This work reports a low-cost and easy manufactured optical fiber bubble Fabry–Perot (FP) interferometer (FPI) sensor with optimized manufacturing parameters. The microbubble sensor is fabricated by welding a multimode fiber (MMF) to a single-mode fiber (SMF), followed by hydrofluoric acid (HF) corroded and discharge treatment at the end of the MMF. The manufacturing process is explored and optimized. The optical power of the interference light was increased and forming stability of the bubbles was improved by controlling the corrosion time, type of arc discharge, discharge intensity, discharge time, and number of discharges. To study the relationship between the optical power and the subjected pressure and temperature, a theoretical model of sensing principle is established, and finite element simulation is carried out to analyze the deformation of bubbles under the influence of the external environment. Experimental results show that the sensor has a pressure sensitivity of
$- 1\times 10^{-{1}}$
dBm/MPa and a temperature sensitivity of
$1.52\,\,{\times }\,\,10^{-{2}}$
dBm/°C. The study gives the influence of multiple preparation parameters on the quality of the sensor, which has good scientific value. The sensor has good prospects in pressure measurement.