Lin Weihao, Liu Yibin, Shao Liyang, Vai Mang I
Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Macau 999078, China.
Micromachines (Basel). 2021 May 20;12(5):586. doi: 10.3390/mi12050586.
We demonstrate a highly sensitive and practical fiber-based temperature sensor system. The sensor is constructed based on a fiber ring laser (FRL) as well as a side-polished fiber filled with isopropanol. The laser cavity of the sensing part fiber is polished by the wheel fiber polishing system with residual thickness (RT) is selected to detect the temperature in the FRL. Thanks to the high thermo-optic coefficient of isopropanol, the sensitivity of the proposed temperature sensor could be effectively improved by filling isopropanol in the cost-less side polished single mode fiber. Refractive index (RI) of isopropanol changes with the surrounding temperature variation allowing high-sensitivity temperature sensing. Experimental results demonstrate that the side polished fiber can efficiently excite high-order cladding modes which enhance the modular interference increase the interaction between the evanescent wave and the isopropanol. Besides, the results show that the sensitivity can be as high as 2 nm/°C in the temperature range of 25-35 °C.
我们展示了一种高度灵敏且实用的基于光纤的温度传感器系统。该传感器基于光纤环形激光器（FRL）以及填充有异丙醇的侧面抛光光纤构建而成。传感部分光纤的激光腔由轮式光纤抛光系统进行抛光，通过选择剩余厚度（RT）来检测FRL中的温度。由于异丙醇具有较高的热光系数，通过在成本较低的侧面抛光单模光纤中填充异丙醇，可有效提高所提出的温度传感器的灵敏度。异丙醇的折射率随周围温度变化而改变，从而实现高灵敏度温度传感。实验结果表明，侧面抛光光纤能够有效地激发高阶包层模，增强模间干涉，增加倏逝波与异丙醇之间的相互作用。此外，结果表明在25 - 35°C的温度范围内，灵敏度可高达2 nm/°C。
