Abstract

Simultaneous assessment of the spectroscopic absorption signal of gas enclosed in a scattering medium and the corresponding optical path length of the probing light is demonstrated using a single setup. Sensitive gas absorption measurements are performed by a tunable diode laser using wavelength-modulation spectroscopy, while the path length is evaluated by the frequency-modulated cw technique commonly used in the field of telecommunication. Proof-of-principle measurements are demonstrated with water vapor as the absorbing gas and using polystyrene foam as an inhomogeneously scattering medium. The combination of these techniques opens up new possibilities for straightforward evaluation of gas presence and exchange in scattering media.

© 2011 Optical Society of America

Combined optical porosimetry and gas absorption spectroscopy in gas-filled porous media using diode-laser-based frequency domain photon migration

Liang Mei, Sune Svanberg, and Gabriel Somesfalean
Opt. Express 20(15) 16942-16954 (2012)

Concentration measurement of gas embedded in scattering media by employing absorption and time-resolved laser spectroscopy

Gabriel Somesfalean, Mikael Sjöholm, Janis Alnis, Claes af Klinteberg, Stefan Andersson-Engels, and Sune Svanberg
Appl. Opt. 41(18) 3538-3544 (2002)

Assessment of photon migration in scattering media using heterodyning techniques with a frequency modulated diode laser

Zuguang Guan, Patrik Lundin, and Sune Svanberg
Opt. Express 17(18) 16291-16299 (2009)

Analysis of gas dispersed in scattering media

M. Sjöholm, G. Somesfalean, J. Alnis, S. Andersson-Engels, and S. Svanberg
Opt. Lett. 26(1) 16-18 (2001)

Optical path-length spectroscopy of wave propagation in random media

G. Popescu and A. Dogariu
Opt. Lett. 24(7) 442-444 (1999)