基于光纤内双开口F-P干涉腔的折射率传感器  

Refractive index sensor based on F-P interferometer cavity in optical fiber with double-openings

作　　者：阙如月 刘一[1] 孙慧慧[1] 曲士良[1] 

机构地区：[1]哈尔滨工业大学理学院,威海264209

出　　处：《激光技术》2014年第6期780-784,共5页Laser Technology

基　　金：国家自然科学基金资助项目(11374077);山东省攻关资助项目(2012GGX10308)

摘　　要：为了实现高灵敏度液体折射率传感器的高效制备,采用飞秒激光直写技术,在光纤末端刻蚀出矩形凹槽,辅以光纤熔接方法,制备出一种基于光纤内双开口法布里-珀罗(F-P)干涉腔的折射率传感器。该传感器的液体折射率传感灵敏度达到1107.76nm/RIU。讨论了温度对该传感器性能的影响,温度串扰小于0.0025nm/℃;基于海水含盐浓度与折射率的线性关系,探讨了该传感器在海水含盐浓度传感测量方面的应用,灵敏度为0.171nm/(mg·mL-1)。结果表明,基于光纤内双开口F-P干涉腔的折射率传感器具有干涉谱对比度高、线性响应良好、灵敏度高、不易受温度串扰、结构紧凑、制备简单高效等优点,在生物、医疗、化学、环境等领域中有着广泛的应用前景。In order to achieve a high sensitive fiber sensor for liquid refractive index （ RI ） measurement through a simple and efficient method , a Fabry-P＆#233;rot interferometer （ F-PI） cavity in fiber with double-openings was fabricated by femtosecond laser micromachining followed by fiber fusion .Firstly a rectangular groove was ablated at the end of fiber by femtosecond laser direct writing .Then the fiber end with the groove was spliced with another fiber end to form the F -PI cavity with double-openings .The responses of the fiber sensor based on the F-PI cavity with double-openings to the liquid RI and temperature were investigated .The experiment results show that the sensitivity of the sensor for RI measurement can achieve 1107.76nm/RIU, and the crosstalk by temperature is less than 0.0025nm/℃.The application of the sensor for seawater salinity measurement was also discussed and its sensitivity achieves 0.171nm/（mg＆#183; mL-1）.This liquid RI fiber sensor based on the F-PI cavity with double-openings can have great application in the fields of biology , medicine, chemistry and environment due to its advantages of high constrast of the reflection spectrum , linear response , high sensitivity, low crosstalk of temperature , small size and simple fabrication .

关 键 词：光学器件 光纤传感器 飞秒激光 法布里-珀罗干涉 折射率 含盐浓度 

分 类 号：TN253[电子电信—物理电子学] TP212.14[自动化与计算机技术—检测技术与自动化装置]