光纤倏逝波化学传感器灵敏度特性研究

Research on the sensitivity of optic fiber evanescent wave chemical sensor

为了克服传统光纤化学传感器的不足,运用宽光谱分析法设计一种基于倏逝波原理的光纤化学传感器,研究了传感器的几何结构参数,溶液浓度与灵敏度的关系。运用光束传播法(BPM)分析传感器几何结构参数与灵敏度的关系;通过化学腐蚀方法制备出不同参数结构的传感器,并用不同浓度亚甲基蓝溶液对这些传感器进行实验验证。实验结果表明,模拟结果与实验结果相符,溶液浓度越大,传感区纤芯越细、越长,灵敏度越高;文章提出的光纤倏逝波化学传感器在水质检测方面有着潜在的应用。

In order to overcome some deficiencies of the traditional optic fiber chemical sensor,an optic fiber chemical sensor based on evanescent wave theory is designed with broadband spectrum analysis. The relationship between sensitivity and geometrical structure parameters,the concentration of solution is investigated. The relationship between sensitivity and geometrical structure parameters is analyzed by the beam propagation method （BPM）. The sensors of different structure parameters were fabricated with chemical corrosion method. The test was carried out for these sensors using the different concentration methylene blue solutions. Experimental results show that the results of simulation and experiment are accordant,and when the concentration of the solution is greater,the core of the sensing region is thinner and longer,the sensitivity of the sensors is higher. The optic fiber chemical sensor has a potential application in the detection of water quality.