以1 330 nm波段的超辐射发光二极管为光源，利用可调谐光纤法珀滤波器为滤光元件，设计了一套光纤煤矿瓦斯传感系统.该系统采用了参考测量方法和差分吸收技术：一路参考光被引出用以消除光源波动的影响；扫描光纤法珀滤波器获得信号光波长和参考光波长，在实现差分吸收测量的同时，避免了不同滤光元件性能差异和中心波长漂移的影响.实验结果表明，所设计的光纤煤矿瓦斯传感系统的最低可探测甲烷浓度为0.15%.

Utilizing a super-luminescent diode (SLD) in 1 330 nm band and a fiber Fabry-Perot tunable filter (FFP-TF), an optical fiber methane sensing system is experimentally demonstrated. The differential absorption technique and a reference method are employed: a reference channel is introduced to eliminate the fluctuation of light source spectrum, and the two wavelengths are acquired by tuning the FFP-TF. The influence of the light source, loss of leading fiber, and the filters′ variations are all avoided. A minimum detectable methane concentration of 0.15% achieved.