内嵌Sagnac干涉结构的光纤环形激光器弯曲传感研究  

Research of curvature sensor based on fiber ring laser with Sagnac interference structure

作　　者：杨帆 吴亚杰 石嘉 徐伟[1] 郭翠娟[1] 白华[1] 张珊珊 徐德刚[2] 姚建铨[2] YANG Fan;WU Ya-jie;SHI Jia;XU Wei;GUO Cui-juan;BAI Hua;ZHANG Shan-shan;XU De-gang;YAO Jian-quan(Tianjin Key Laboratory of Optoelectronic Detection Technology and System,Shool of Electronics and Imformation Engineering,Tiangong University,Tianjin 300387,China;Key Laboratory of Opto-Electronics InformationTechnology(Ministry of Education),School of Precision Instruments and Opto-Electronic Engineering Tianjin University,Tianjin 300072,China)

机构地区：[1]天津市光电检测技术与系统重点实验室,天津工业大学电子与信息工程学院,天津300387 [2]光电信息技术教育部重点实验室,天津大学精密仪器与光电子工程学院,天津300072

出　　处：《光电子．激光》2020年第11期1124-1130,共7页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(61905177,61735010,61771332,61675147);天津市自然科学基金(19JCQNJC01400,14JCQNJC01800);天津市重点研发计划科技支撑重点项目(18YFZNGX00040);陆军军医大学电磁辐射医学防护教育部重点实验室开放基金资助(2018DCKF002);中国博士后科学基金(2019M651035,2019M661013)资助项目。

摘　　要：本文报道了一种基于光纤环形激光器的弯曲传感器,将基于单模-保偏-单模的光纤Sagnac干涉结构作为弯曲传感元件和滤波器插入到光纤环形激光器中。光纤Sagnac干涉光谱的滤波特性受保偏光纤弯曲曲率调制﹐在激光器环型腔内形成了曲率可调谐的滤波器,通过测量激光输出能量实现光纤激光器内腔弯曲传感。本文从理论上分析了传感系统的工作原理,并通过实验验证了高分辨率弯曲传感的可行性。实验结果表明,在0 m^-1-5.6865 m^-1曲率范围内,传感器可达到的最大分辨率为6.5×10^-8m^-1。采用激光器内腔强度调制方式,曲率分辨水平从10^-4m^-1提高到了10^-8m^-1。该传感器具有结构简单,易于制造的特点,在建筑结构健康监测、结构微弯曲角度测量等领域有潜在的应用前景。A curvature sensor based on fiber ring laser is reported in this paper.The Sagnac loop based onsingle-mode-polarization-maintaining-single-mode is inserted into a fiber ring laser served as the curva-ture sensing element and the filter.The spectrum of the Sagnac loop is modulated by the curvature,which formed a curvature tunable filter in the laser cavity.The intracavitary fiber ring laser is used tonarrow the corresponding 3 dB bandwidth and enhance the resolution of the curvature sensor.The curva-ture will be measured by detecting the output power of this system.The working mechanism of the sens-ing system is analyzed theoretically,and the feasibility of the high-resolution curvature sensor is verifiedthrough experiments.The experimental results show that the highest curvature resolution of 6.5×10^-8m^-1is obtained within the curvature range from 0 m^-1to 5.6865 m^-1.With the method based on intra-cavity sensing,the curvature resolution level of the sensing system has been improved from 10^-4m^-1 to 10^-8m^-1.At the same time the system stability and measurement error are measured in the experiment.Due to its advantages of simple structure,easy to manufacture and low cost,the sensor has a potential application prospect in the field of building structure health monitoring and micro-bending angle measurement.

关 键 词：弯曲传感器 光纤激光器 高分辨率 光纤Sagnac干涉结构 

分 类 号：TN253[电子电信—物理电子学]