物理学报2018，Vol.67Issue(2)：144-151,8.DOI:10.7498/aps.67.20171677
基于光纤锥和纤芯失配的Mach-Zehnder干涉湿度传感器
Mach-Zehnder interferometer based on fiber taper and fiber core mismatch for humidity sensing
摘要
Abstract
A simple and high sensitivity optical fiber relative humidity (RH) sensor based on Mach-Zehnder interferometer (MZI) is proposed and demonstrated in this paper. A single-mode fiber and a graded-index multimode fiber are con-nected by a fiber taper to form a section. Then an uncoated dispersion compensation fiber is sandwiched between two short sections of the graded-index multimode fiber.Therefore, a sensing structure is set up as a single-mode fiber-taper fiber-graded-index multimode fiber-dispersion compensation fiber-graded-index multimode fiber-taper laser-single-mode fiber. The taper fiber is used to augment the energy of the cladding mode. The two nodes of the graded-index multi-mode fiber can be looked as a mode coupler. Thus an MZI is constructed. Since the external RH change can make the transmission spectrum energy changed,we can obtain the RH by detecting the peak energy variation of the interference pattern induced by the evanescent-field interaction. The experimental results show that the peak energy changes lin-early with surrounding relative humidity. Under the condition of 35%Rh–85%RH, the sensitivity of the sensor with a 20 mm dispersion compensation fiber is ?0.0668 dB/%RH and the linearity is 0.995. Moreover, temperature response characteristics are investigated. Experimental results suggest that the transmission spectrum energy of the sensor is insensitive to temperature. With temperature increasing, the transmission spectrum presents obviously a red-shift, yet the peak energy of the monitoring point barely moves, which demonstrates its potential for measuring simultaneously RH and temperature. The proposed sensor has a small size and simple manufacturing process,which can make it widely used to measure RH.关键词
湿度传感器/色散补偿光纤/多模渐变光纤/Mach-Zehnder干涉仪Key words
humidity sensors/dispersion compensation fiber/graded-index multimode fiber/Mach-Zehnder interferometer引用本文复制引用
程君妮..基于光纤锥和纤芯失配的Mach-Zehnder干涉湿度传感器[J].物理学报,2018,67(2):144-151,8.基金项目
陕西省榆林科学技术局产学研基金(批准号:2015cxy-22)和陕西省榆林学院校内项目(批准号:JG-1527)资助的课题. Project supported by the Research Foundation of Science and Technology Board of Yulin, Shaanxi, China (Grant No. 2015cxy-22) and the Fundamental Research Funds for Yulin University, China (Grant No. JG-1527). （批准号:2015cxy-22）
