介绍了可调谐二极管激光吸收光谱法测量煤矿瓦斯气体的基本原理 ,给出了测量系统的结构框图。该方法是利用可调谐二极管发出激光 ,经准直后 ,再经过一段距离的传输 ,由望远镜来接受 ,在传输中 ,由于瓦斯气体分子对光在一定波段有吸收特性 ,使光谱反映了瓦斯的特性。通过与光源发出的光进行比较 ,反演瓦斯气体在矿井中的浓度。该方法克服了传统方法如气相色谱法实时性差的缺点 ,实现了完全非接触在线自动监测 ,真实反映矿井瓦斯的浓度。

In this paper,principles of measuring gas on coal mine according to tunable diode laser abaorption spectroscopy are introduced and outline of this measuring system is given.In this system,laser is sent from tunable diode firstly,then will be collimated by a telescope,and then after a distance of propagation will be received by the telescope.After the spectrum propagation will reflect the character of gas because gas absorbs light in some bands,The density of gas can be reflected by comparing the received light and the original one.In this system,weakness of poor real-time character of traditional methods such as Chromatogram of Gas Plase is eliminated,and also complete untouched online automonitoring is realized.So the densith of gas can be reflected accurately.