分析和仿真了含两段保偏光纤的光纤Sagnac干涉仪输出光谱特性,获得消除两段双折射光纤交叉敏感的条件。提出了一种基于保偏光子晶体光纤Sagnac干涉仪的温度不敏感压力传感技术。采用实心保偏光子晶体光纤作为传感光纤,搭建了基于双段保偏光子晶体光纤Sagnac干涉仪的侧向压力传感系统,分别进行侧向压力测试及温度影响实验。实验结果表明,侧向压力灵敏度可以达到的0.287 7 nm/N,同时由温度变化引起的漂移量小于0.1 pm/℃。
The transmission spectrum characteristic of two-segment polarization maintaining fibers Sagnac interferometer was investigated and simulated in detail and the optimal parameters for eliminating the crosstalk between the two polarization maintaining fibers was obtained. A temperature-insensitive pressure sensing technology was proposed. An experimental Sagnac interferometer was built and the solid core polarization maintaining photonic crystal fibers were taken as the sensing probe. The side pressure sensitive coefficients and the temperature crosstalk drift were measured and compared. The experimental results show that the side pressure sensitive coefficient was about 0.287 7 nm/N and the temperature drift was less than 0.1 pm/℃.