[1] Yin Jian, Liu Junbo, Li Xuelai. Fiber methane sensor in coal mines［J］. Safety in Coal Mines, 2005, 36(4): 39~41

[2] Yu Hongbo, Liao Yanbiao, Jin Wei et al.. Review of the optical fiber gas sensor［J］. Laser and Infrared, 2002, 23(3): 193~196

[3] Wang Tieyun, Zhang Lei, Dong Lei et al.. Minimum detection limit for methane with single laser remote sensing［J］. Chinese J. Lasers, 2006, 33(3): 405~407

[4] J. Reid. Second-harmonic detection with tunable diode lasers-comparison of experiment and theory［J］. Appl. Phys. B, 1981, 26(3): 203~210

[5] Ruifeng Kan,Wenqing Liu, Yunjun Zhang et al.. A high sensitivity spectrometer with tunable diode laser for ambient methane monitoring［J］. Chin. Opt. Lett., 2007, 5(1): 54~57

[6] Wang Yutian, Liu Jin, Zhang Jingchao et al.. A methane gas sensor with optic fiber based on frequency harmonic detection technique［J］. Measurement and Control Technology, 2003, 22(11): 19~21

[7] B. Culshaw, G. Stewart, F. Dong et al.. Fibre optic techniques for remote spectroscopic methane detection-from concept to system realization［J］. Sensors and Actuators B, 1998, 51(1-3): 25~37

[8] Jiang Desheng, Ran Changyan, Bo Junjie et al.. Demodulation system of spectrum absorptive optical fiber gas sensor［J］. Optics and Optoelectronic Technology, 2005, 3(4): 8~10