可调谐二极管激光吸收光谱法测量环境空气中的甲烷含量

Absorption measurements of ambient methane with tunable diode laser

可调谐二极管激光吸收光谱法是在二极管激光器与长光程吸收池技术相结合的基础上发展起来的一种新的痕量气体检测方法 .这种方法不仅精度较高、选择性强而且响应速度快 .介绍了一套可调谐二极管激光吸收光谱检测甲烷浓度的实验装置 .这套装置具有灵敏度高、检测限低 (低于 0 0 87mg m3)、易于集成为便携式痕量气体检测仪等优点 ,利用这套装置实现了对环境空气中甲烷含量的检测 .

Tunable diode laser absorption spectroscopy (TDLAS) is a new trace gas detective method developed with the combination of a diode laser source and a long absorption path. It has the significant advantage not only in sensitivity but also in rapidity of response. The concentration of the ambient methane has been measured using a TDLAS system developed in the laboratory. The system has some advantages, such as sensitivity, low detective limit (below 0.087 mg/m(3)) and rapidity of response, and also it is easy to be integrated to a portable apparatus to monitor the methane concentration in the atmosphere.