基于波分复用的长周期光纤光栅光化学多参量传感技术研究  

Multi-Parameter Photochemical Sensing Technology of Long-Period Fiber Grating and Wavelength Division Multiplexing

作　　者：陈海云[1,2,3] 顾铮■ 高侃[4] 

机构地区：[1]上海理工大学光电信息与计算机工程学院,上海200093 [2]浙江师范大学信息光学研究所,浙江金华321004 [3]上海理工大学理学院光电功能薄膜实验室,上海200093 [4]中国电子科技集团第二十三研究所,上海201900

出　　处：《中国激光》2014年第2期264-271,共8页Chinese Journal of Lasers

基　　金：国家自然科学基金(60777035);教育部科学技术研究重点项目(208040);上海市教育委员会科研项目(11ZZ131);上海市重点学科建设项目(S30502)

摘　　要：提出一种基于波分复用(WDM)的长周期光纤光栅(LPFG)光化学多参量传感技术。利用均匀LPFG相邻级次包层模耦合谐振峰间的波长间隔,通过设计不同传感单元LPFG的光栅周期,进一步通过包层腐蚀或镀膜调整各LPFG特征峰位置,使各LPFG的特征峰在观察波长范围内相互错位。前一个LPFG激发的包层模不能传输到下一个LPFG,不同参量变化引起的各LPFG特征峰移动相互独立,通过考察系统输出复合谱中各特征峰的偏移可得各参量值。实验中利用镀聚炳烯胺盐酸盐/聚丙烯酸(PAH/PAA)薄膜LPFG、薄包层LPFG和镀TiO2/SnO2复合薄膜LPFG组成多参量传感系统,实现了对pH值、NaCl溶液浓度和相对湿度(RH)三个参量的传感。基于WDM的LPFG光化学多参量传感原理与结构简单,各LPFG的结构设计可独立进行,适用于对多个光化学环境参量的分布式测量。A multi-parameter photochemical sensing technology of long-period fiber gratings （LPFGs） based on wavelength division multiplexing （WDM） is put forward. Utilizing the wide wavelength space between two resonance peaks corresponding to two neighboring cladding modes of a uniform LPFG, the characteristic peaks of respective sensing units in the multi-parameter sensing system are tuned to distribute in the wavelength space discretely by designing grating periods of different sensor units of LPFG, eroding cladding or depositing films on cladding. There is no cladding modes interference between LPFGs and the peak shifts induced by the variations of corresponding parameters are independent, and finally the respective parameters are obtained by directly interrogating the corresponding characteristic peaks. In the experiment, a multi-parameter photochemical sensing system consisting ofLPFG coated with polypropylene amine hydrochloride/polyacrylic acid （PAH/PAA） film, thin cladding LPFG and LPFG coated with TiO2/Sn02 composite film is set up, which can perform the measurements of pH value, concentration of NaC1 solution and relative humidity （RH）, respectively. The sensing mechanism and system structure of this WDM-based LPFG multi-parameter photochemical sensing technology are simple and the design of respective sensing units can be carried out independently, which enables this technology to be applied in the distributed sensing of multiple environmental nararneters.

关 键 词：光纤光学 长周期光纤光栅 波分复用 多参量传感 敏感薄膜 

分 类 号：TN253[电子电信—物理电子学]