在对甲烷气体分子近红外吸收光谱分析的基础上,采用1.66 μm分布反馈式半导体激光器作为光源,应用二次谐波检测技术,实现对甲烷气体的浓度检测,检测的灵敏度为7×10^-5/m.大气和工业污染中的其他气体分子的含量也可通过调换光源及相应的光学器件采用类似的方法测量.
Based on analysis of the near infrared spectral absorption of methane, a methane gas test method using 1.66μm DFB LD light source and second-harmonic detection technique is demonstrated. Test sensitivity of 7×10^-5/m was achieved with this method. The concentration of other gases in the atmosphere and industry pollution can also be tested using the same method and just changing light source and optical apparatus corresponding to the target gas.