Journal of Atmospheric and Environmental Optics ›› 2011, Vol. 6 ›› Issue (2): 95-.

• 论文 • Previous Articles     Next Articles

Atmospheric Water Vapor Concentration Measurement Method Based on Tunable Diode Laser Absorption Spectroscopy

XU Zhen-yu, LIU Wen-qing, KAN Rui-feng, ZHANG Yu-jun, ZHANG Shuai, SHU Xiao-wen, HE Ying, ZHANG Liang, TANG Yuan-yuan   

  1. (Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Science, Hefei 230031, China)
  • Received:2010-05-04 Published:2011-03-29

Abstract:

A water vapor concentration measurement method was studied based on direct absorption spectroscopy techniques. Using DFB diode laser as light source, the concentration of water vapor is obtained through the integrated absorbance inversion. First a low-order polynomial baseline fitting was carried out on sub-regions of the transmitted signal to eliminate the effect of diode-laser output power fluctuation and the absorbance curve was obtained. Then integrated absorbance can be inverted through line-shape fitting using Levenberg-Marquardt non-linear least-squares fitting method. Two absorption lines for concentration measurement near 1.4 of water vapor were selected to verify the method.

Key words: atmospheric water vapor, direct-absorption spectroscopy, absorbance, non-linear least-squares method

CLC Number: