Efficiency improvement of an optical fiber fluorescent temperature sensor using a spherical fiber probe design

摘要

This paper presents a sphere fiber probe design for fluorescence temperature sensor based on lifetime measurement and focuses on the structural and coupling analysis of the stimulated fluorescence to light-source and optic fiber. A theoretical model taking advantage of geometric optics is built to estimate the effectiveness of the probe design. A standard 62.5/125μm multimode fiber with a spherical end and the least squares fitting method are adopted in the sensing system for the fluorescence lifetime demodulation. Experiment results of temperature range from 17°C to 77 °C demonstrate an efficiency increment of 82.36%, which matches well with the simulation.