Zhang Shuai, Dong Feng-Zhong, Zhang Zhi-Rong, Wang Yu, Kan Rui-Feng, Zhang Yu-Jun, Liu Jian-Guo, Liu Wen-Qing
Key Laboratory of Environmental Optics & Technology, Anhui Institute of Optics & Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2009 Oct;29(10):2593-6.
Oxygen is a widely used important gas in the industrial process. It is very meaningful to on-line monitor the oxygen concentration for the enhancement of combustion efficiency and reduction in environmental pollution. Tunable diode laser absorption spectroscopy (TDLAS) is a highly sensitive, highly selective and fast time response trace gas detection technique. With the features of tunability and narrow linewidth of distributed feedback (DFB) diode laser and by precisely tuning the laser output wavelength to a single isolated absorption line of the gas, TDLAS technique can be utilized to accurately implement gas concentration measurement with very high sensitivity. In the present paper, the authors used a DFB laser was used as the light source, and by employing wavelength modulation method and measuring the second harmonic signal of one absorption line near 760 nm of oxygen molecule, the authors built a system for online monitoring of oxygen concentration. The characteristics of the system are as follows: the scope of detection is 0.01%-20%; detection accuracy is 0.1%, long term stability is 1%.
氧气是工业过程中广泛使用的重要气体。在线监测氧气浓度对于提高燃烧效率和减少环境污染具有重要意义。可调谐二极管激光吸收光谱法（TDLAS）是一种高灵敏度、高选择性且时间响应快的痕量气体检测技术。利用分布反馈（DFB）二极管激光器的可调谐性和窄线宽特性，通过将激光输出波长精确调谐到气体的单一孤立吸收线，TDLAS技术可用于以非常高的灵敏度精确实现气体浓度测量。在本文中，作者使用DFB激光器作为光源，采用波长调制方法并测量氧分子760nm附近一条吸收线的二次谐波信号，构建了一个氧气浓度在线监测系统。该系统的特点如下：检测范围为0.01%-20%；检测精度为0.1%，长期稳定性为1%。
