Diode Laser Detection of Greenhouse Gases in the Near-Infrared Region by Wavelength Modulation Spectroscopy: Pressure Dependence of the Detection Sensitivity

Sensors

Takashi Asakawa¹  Nozomu Kanno² 

[1] Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan; E-Mail:;Department of Micro-Nano Systems Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan; E-Mail:

关键词: gas sensing;    wavelength modulation spectroscopy;    near-infrared absorption spectroscopy;   

DOI  :  10.3390/s100504686

来源: mdpi

【 摘 要 】

We have investigated the pressure dependence of the detection sensitivity of CO₂, N₂O and CH₄ using wavelength modulation spectroscopy (WMS) with distributed feed-back diode lasers in the near infrared region. The spectral line shapes and the background noise of the second harmonics (2f) detection of the WMS were analyzed theoretically. We determined the optimum pressure conditions in the detection of CO₂, N₂O and CH₄, by taking into consideration the background noise in the WMS. At the optimum total pressure for the detection of CO₂, N₂O and CH₄, the limits of detection in the present system were determined.

【 授权许可】

CC BY   
© 2010 by the authors; licensee MDPI, Basel, Switzerland.