Near-infrared diode laser wavelength modulation-based photoacoustic spectrometer.
An inexpensive resonant photoacoustic spectrometer based on a low-power distributed feedback diode laser and wavelength modulation spectroscopy is developed. This sensor has been applied to the detection of acetylene (C2H2) using a properly designed photoacoustic cell operating on its second longitudinal mode. The minimum detectable limit of about 10 parts-per-million volume (signal to noise ratio=1) is achieved at atmospheric pressure, and the pressure and laser power linear dependence of the photoacoustic signal is also investigated. Moreover, in this paper we also describe some basic theory of gas photoacoustic spectroscopy.
Li
Jingsong
J
Environmental Spectroscopy Laboratory, Anhui Institute of Optics & Fine Mechanics, Chinese Academy Sciences, P.O. Box 1125, Hefei 230031, PR China. ljs0625@126.com
Gao
Xiaoming
X
Li
Weizheng
W
Cao
Zhensong
Z
Deng
Lunhua
L
Zhao
Weixiong
W
Huang
Mingqiang
M
Zhang
Weijun
W
D000162:Acoustics; D005030:Ethylenes / Q000737:chemistry; D007834:Lasers; D010783:Photometry; D012680:Sensitivity and Specificity; D019265:Spectroscopy, Near-Infrared / Q000295:instrumentation*
D005030:Ethylenes; C036216:ethylene