甲烷气体近红外光声光谱及痕量探测技术研究

Study of Near-infrared Photoacoustic Spectroscopy and Trace Detection Technology of CH_4

介绍了一种基于1.653μm分布反馈式(DFB)半导体激光器的共振光声光谱系统。该系统具有结构简单、操作方便、价格低廉等优点。对光声光谱系统的响应特性进行了实验研究,对光声光谱系统进行振幅调制和波长调制两种方法进行了实验对比研究。并用此系统对室外空气中的甲烷(CH_4)进行了测量,探测灵敏度可达100 ppbv。

The resonant photoacoustic spectroscopy gas sensor based on distributed feedback(DFB)diode laser operating at 1.65μm was described.The sensor had many advantages such as high selectivity and sensitivity, on-line and real time measurements,compact size and low cost and so on.The response characterizations of the sensor were experimentally investigated.The comparison of the two approaches,amplitude modulation and wavelength modulation,were carried out.The methane(CH_4)in air was measured with this sensor and the detection sensitivity of 100 ppbv was obtained.