An optical sensor for hydrogen sulfide detection in open path using WMS-2f/1f technique  

作　　者：宋丽梅 刘力文 杨燕罡 郭庆华 习江涛 

机构地区：[1]Key Laboratory of Advanced Electrical Engineering and Energy Technology, Tianjin Polytechnic University, Tianjin 300387, China [2]Tianjin University of Technology and Education, Tianjin 300222, China [3]School of Electrical, Computer and Telecommunications Engineering, University of Wollongong, Wollongong 2500, Australia

出　　处：《Optoelectronics Letters》2016年第6期465-468,共4页光电子快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.60808020 and 61078041);the Natural Science Foundation of Tianjin(Nos.16JCQNJC02100,15JCYBJC51700 and 16JCYBJC15400);the National Science and Technology Support(No.2014BAH03F01)

摘　　要：An optical hydrogen sulfide(H_2S) sensor based on wavelength modulation spectroscopy with the second harmonic(2f) corrected by the first harmonic(1f) signal(WMS-2f/1f) is developed using a distributed feedback(DFB) laser emitting at 1.578 μm and a homemade gas cell with 1-m-long optical path length. The novel sensor is constructed by an electrical cabinet and an optical reflecting and receiving end. The DFB laser is employed for targeting a strong H_2S line at 6 336.62 cm^(-1) in the fundamental absorption band of H_2S. The sensor performance, including the minimum detection limit and the stability, can be improved by reducing the laser intensity drift and common mode noise by means of the WMS-2f/1f technique. The experimental results indicate that the linearity and response time of the sensor are 0.999 26 and 6 s(in concentration range of 15.2—45.6 mg/m^3), respectively. The maximum relative deviation for continuous detection(60 min) of 30.4 mg/m^3 H_2S is 0.48% and the minimum detection limit obtained by Allan variance is 79 μg/m^3 with optimal integration time of 32 s. The optical H_2S sensor can be applied to environmental monitoring and industrial production, and it has significance for real-time online detection in many fields.

关 键 词：corrected sulfide deviation Allan reflecting harmonic targeting drift linearity length 

分 类 号：TH744.4[机械工程—光学工程]