@article{(Open Science Index):https://publications.waset.org/pdf/9999737,
	  title     = {Short-Path Near-Infrared Laser Detection of Environmental Gases by Wavelength-Modulation Spectroscopy},
	  author    = {Isao Tomita},
	  country	= {},
	  institution	= {},
	  abstract     = {The detection of environmental gases, 12CO2, 13CO2,
and CH4, using near-infrared semiconductor lasers with a short
laser path length is studied by means of wavelength-modulation
spectroscopy. The developed system is compact and has high
sensitivity enough to detect the absorption peaks of isotopic 13CO2
of a 3-% CO2 gas at 2 μm with a path length of 2.4 m, where
its peak size is two orders of magnitude smaller than that of the
ordinary 12CO2 peaks. In addition, the detection of 12CO2 peaks of
a 385-ppm (0.0385-%) CO2 gas in the air is made at 2 μm with a
path length of 1.4 m. Furthermore, in pursuing the detection of an
ancient environmental CH4 gas confined to a bubble in ice at the
polar regions, measurements of the absorption spectrum for a trace
gas of CH4 in a small area are attempted. For a 100-% CH4 gas
trapped in a ∼ 1 mm3 glass container, the absorption peaks of CH4
are obtained at 1.65 μm with a path length of 3 mm, and also the
gas pressure is extrapolated from the measured data.
},
	    journal   = {International Journal of Electrical and Computer Engineering},
	  volume    = {8},
	  number    = {11},
	  year      = {2014},
	  pages     = {1251 - 1254},
	  ee        = {https://publications.waset.org/pdf/9999737},
	  url   	= {https://publications.waset.org/vol/95},
	  bibsource = {https://publications.waset.org/},
	  issn  	= {eISSN: 1307-6892},
	  publisher = {World Academy of Science, Engineering and Technology},
	  index 	= {Open Science Index 95, 2014},
	}