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

Liang Mei; Sune Svanberg; Gabriel Somesfalean

doi:10.1364/OE.20.016942

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

Optics Express
Vol. 20,
Issue 15,
pp. 16942-16954
(2012)
•https://doi.org/10.1364/OE.20.016942

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Liang Mei, Sune Svanberg, and Gabriel Somesfalean, "Combined optical porosimetry and gas absorption spectroscopy in gas-filled porous media using diode-laser-based frequency domain photon migration," Opt. Express 20, 16942-16954 (2012)

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Related Topics
Table of Contents Category
- Spectroscopy
Optics & Photonics Topics
?

The topics in this list come from the OSA Optics and Photonics Topics applied to this article.
Previously assigned OCIS codes
- Multiple scattering (290.4210)
- Absorption (300.1030)

About this Article
History
- Original Manuscript: April 9, 2012
- Revised Manuscript: May 26, 2012
- Manuscript Accepted: May 27, 2012
- Published: July 11, 2012
Virtual Issues
Virtual Journal for Biomedical Optics Vol. 7, Iss. 9

Accessible

Open Access

Abstract

A combination method of frequency domain photon migration (FDPM) and gas in scattering media absorption spectroscopy (GASMAS) is used for assessment of the mean optical path length (MOPL) and the gas absorption in gas-filled porous media, respectively. Polystyrene (PS) foams, with extremely high physical porosity, are utilized as sample materials for proof-of-principle demonstration. The optical porosity, defined as the ratio between the path length through the pores and the path length through the medium, is evaluated in PS foam and found consistent with the measured physical porosity. The method was also utilized for the study of balsa and spruce wood samples.

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References

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Publication

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[Crossref] [PubMed]
A. G. Hendricks, U. Vandsburger, W. R. Saunders, and W. T. Baumann, “The use of tunable diode laser absorption spectroscopy for the measurement of flame dynamics,” Meas. Sci. Technol. 17(1), 139–144 (2006).
[Crossref]
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[Crossref]
G. Somesfalean, J. Alnis, U. Gustafsson, H. Edner, and S. Svanberg, “Long-path monitoring of NO2 with a 635 nm diode laser using frequency-modulation spectroscopy,” Appl. Opt. 44(24), 5148–5151 (2005).
[Crossref] [PubMed]
A. Puiu, G. Giubileo, and C. Bangrazi, “Laser sensors for trace gases in human breath,” Int. J. Environ. an. Ch. 85(12-13), 1001–1012 (2005).
[Crossref]
P. C. Kamat, C. B. Roller, K. Namjou, J. D. Jeffers, A. Faramarzalian, R. Salas, and P. J. McCann, “Measurement of acetaldehyde in exhaled breath using a laser absorption spectrometer,” Appl. Opt. 46(19), 3969–3975 (2007).
[Crossref] [PubMed]
P. Werle, “A review of recent advances in semiconductor laser based gas monitors,” Spectrochim. Acta [A] 54(2), 197–236 (1998).
[Crossref]
M. Sjöholm, G. Somesfalean, J. Alnis, S. Andersson-Engels, and S. Svanberg, “Analysis of gas dispersed in scattering media,” Opt. Lett. 26(1), 16–18 (2001).
[Crossref] [PubMed]
M. Lewander, Z. G. Guan, L. Persson, A. Olsson, and S. Svanberg, “Food monitoring based on diode laser gas spectroscopy,” Appl. Phys. B 93(2-3), 619–625 (2008).
[Crossref]
M. Andersson, L. Persson, M. Sjöholm, and S. Svanberg, “Spectroscopic studies of wood-drying processes,” Opt. Express 14(8), 3641–3653 (2006).
[Crossref] [PubMed]
M. Lewander, Z. G. Guan, K. Svanberg, S. Svanberg, and T. Svensson, “Clinical system for non-invasive in situ monitoring of gases in the human paranasal sinuses,” Opt. Express 17(13), 10849–10863 (2009).
[Crossref] [PubMed]
T. Svensson and Z. J. Shen, “Laser spectroscopy of gas confined in nanoporous materials,” Appl. Phys. Lett. 96(2), 021107 (2010).
[Crossref]
T. Svensson, M. Lewander, and S. Svanberg, “Laser absorption spectroscopy of water vapor confined in nanoporous alumina: wall collision line broadening and gas diffusion dynamics,” Opt. Express 18(16), 16460–16473 (2010).
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[Crossref] [PubMed]
G. Somesfalean, M. Sjöholm, J. Alnis, C. Klinteberg, S. Andersson-Engels, and S. Svanberg, “Concentration measurement of gas embedded in scattering media by employing absorption and time-resolved laser spectroscopy,” Appl. Opt. 41(18), 3538–3544 (2002).
[Crossref] [PubMed]
T. Svensson, E. Alerstam, J. Johansson, and S. Andersson-Engels, “Optical porosimetry and investigations of the porosity experienced by light interacting with porous media,” Opt. Lett. 35(11), 1740–1742 (2010).
[Crossref] [PubMed]
T. Svensson, M. Andersson, L. Rippe, S. Svanberg, S. Andersson-Engels, J. Johansson, and S. Folestad, “VCSEL-based oxygen spectroscopy for structural analysis of pharmaceutical solids,” Appl. Phys. B 90(2), 345–354 (2008).
[Crossref]
T. Svensson, E. Adolfsson, M. Lewander, C. T. Xu, and S. Svanberg, “Disordered, strongly scattering porous materials as miniature multipass gas cells,” Phys. Rev. Lett. 107(14), 143901 (2011).
[Crossref] [PubMed]
L. Mei, H. Jayaweera, P. Lundin, S. Svanberg, and G. Somesfalean, “Gas spectroscopy and optical path-length assessment in scattering media using a frequency-modulated continuous-wave diode laser,” Opt. Lett. 36(16), 3036–3038 (2011).
[Crossref] [PubMed]
J. K. Link, “Measurement of radiative lifetimes of first excited states of Na, K, Rb, and Cs by means of phase-shift method,” J. Opt. Soc. Am. 56(9), 1195–1199 (1966).
[Crossref]
G. Jönsson, C. Levinson, and S. Svanberg, “Natural radiative lifetimes and Stark-shift parameters in the 4p2 configuration in Ca I,” Phys. Scr. 30(1), 65–69 (1984).
[Crossref]
B. J. Tromberg, O. Coquoz, J. B. Fishkin, T. Pham, E. R. Anderson, J. Butler, M. Cahn, J. D. Gross, V. Venugopalan, and D. Pham, “Non-invasive measurements of breast tissue optical properties using frequency-domain photon migration,” Philos. Trans. R. Soc. Lond. B Biol. Sci. 352(1354), 661–668 (1997).
[Crossref] [PubMed]
S. J. Erickson and A. Godavarty, “Hand-held based near-infrared optical imaging devices: A review,” Med. Eng. Phys. 31(5), 495–509 (2009).
[Crossref] [PubMed]
Z. G. Sun, Y. Q. Huang, and E. M. Sevick-Muraca, “Precise analysis of frequency domain photon migration measurement for characterization of concentrated colloidal suspensions,” Rev. Sci. Instrum. 73(2), 383–393 (2002).
[Crossref]
S. R. Arridge, M. Cope, and D. T. Delpy, “The theoretical basis for the determination of optical pathlengths in tissue - temporal and frequency analysis,” Phys. Med. Biol. 37(7), 1531–1560 (1992).
[Crossref] [PubMed]
R. Coquard and D. Baillis, “Modeling of heat transfer in low-density EPS foams,” J. Heat Trans. 128(6), 538–549 (2006).
[Crossref]
J. Alnis, B. Anderson, M. Sjöholm, G. Somesfalean, and S. Svanberg, “Laser spectroscopy of free molecular oxygen dispersed in wood materials,” Appl. Phys. B 77, 691–695 (2003).
[Crossref]
B. Chance, M. Cope, E. Gratton, N. Ramanujam, and B. Tromberg, “Phase measurement of light absorption and scatter in human tissue,” Rev. Sci. Instrum. 69(10), 3457–3481 (1998).
[Crossref]
Y. S. Yang, H. L. Liu, X. D. Li, and B. Chance, “Low-cost frequency-domain photon migration instrument for tissue spectroscopy, oximetry, and imaging,” Opt. Eng. 36(5), 1562–1569 (1997).
[Crossref]
P. Kluczynski and O. Axner, “Theoretical description based on Fourier analysis of wavelength-modulation spectrometry in terms of analytical and background signals,” Appl. Opt. 38(27), 5803–5815 (1999).
[Crossref] [PubMed]
T. Fernholz, H. Teichert, and V. Ebert, “Digital, phase-sensitive detection for in situ diode-laser spectroscopy under rapidly changing transmission conditions,” Appl. Phys. B 75(2-3), 229–236 (2002).
[Crossref]
M. Andersson, L. Persson, T. Svensson, and S. Svanberg, “Flexible lock-in detection system based on synchronized computer plug-in boards applied in sensitive gas spectroscopy,” Rev. Sci. Instrum. 78(11), 113107 (2007).
[Crossref] [PubMed]
M. Yamauchi, Y. Yamada, and Y. Hasegawa, “Frequency-domain measurements of diffusing photon propagation in solid phantoms,” Opt. Rev. 4(5), 620–621 (1997).
[Crossref]
D. Contini, F. Martelli, and G. Zaccanti, “Photon migration through a turbid slab described by a model based on diffusion approximation. I. Theory,” Appl. Opt. 36(19), 4587–4599 (1997).
[Crossref] [PubMed]
L. Mei, P. Lundin, S. Andersson-Engels, S. Svanberg, and G. Somesfalean, “Characterization and validation of the frequency-modulated continuous-wave technique for assessment of photon migration in solid scattering media,” Appl. Phys. B DOI 10.1007/s00340-00012-05103-00349 (2012).
N. Ramanujam, C. Du, H. Y. Ma, and B. Chance, “Sources of phase noise in homodyne and heterodyne phase modulation devices used for tissue oximetry studies,” Rev. Sci. Instrum. 69(8), 3042–3054 (1998).
[Crossref]
K. Alford and Y. Wickramasinghe, “Phase-amplitude crosstalk in intensity modulated near infrared spectroscopy,” Rev. Sci. Instrum. 71(5), 2191–2195 (2000).
[Crossref]
S. P. Morgan and K. Y. Yong, “Elimination of amplitude-phase crosstalk in frequency domain near-infrared spectroscopy,” Rev. Sci. Instrum. 72(4), 1984–1987 (2001).
[Crossref]
J. Carlsson, P. Hellentin, L. Malmqvist, A. Persson, W. Persson, and C. G. Wahlström, “Time-resolved studies of light propagation in paper,” Appl. Opt. 34(9), 1528–1535 (1995).
[Crossref] [PubMed]
S. N. Kasarova, N. G. Sultanova, C. D. Ivanov, and I. D. Nikolov, “Analysis of the dispersion of optical plastic materials,” Opt. Mater. 29(11), 1481–1490 (2007).
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A. Da Silva and S. Kyriakides, “Compressive response and failure of balsa wood,” Int. J. Solids Struct. 44(25-26), 8685–8717 (2007).
[Crossref]
J. G. Rivas, D. H. Dau, A. Imhof, R. Sprik, B. P. J. Bret, P. M. Johnson, T. W. Hijmans, and A. Lagendijk, “Experimental determination of the effective refractive index in strongly scattering media,” Opt. Commun. 220(1-3), 17–21 (2003).
[Crossref]
K. Yoshitani, M. Kawaguchi, T. Okuno, T. Kanoda, Y. Ohnishi, M. Kuro, and M. Nishizawa, “Measurements of optical pathlength using phase-resolved spectroscopy in patients undergoing cardiopulmonary bypass,” Anesth. Analg. 104(2), 341–346 (2007).
[Crossref] [PubMed]

2012 (1)

L. Mei, P. Lundin, S. Andersson-Engels, S. Svanberg, and G. Somesfalean, “Characterization and validation of the frequency-modulated continuous-wave technique for assessment of photon migration in solid scattering media,” Appl. Phys. B DOI 10.1007/s00340-00012-05103-00349 (2012).

2011 (2)

T. Svensson, E. Adolfsson, M. Lewander, C. T. Xu, and S. Svanberg, “Disordered, strongly scattering porous materials as miniature multipass gas cells,” Phys. Rev. Lett. 107(14), 143901 (2011).
[Crossref] [PubMed]

L. Mei, H. Jayaweera, P. Lundin, S. Svanberg, and G. Somesfalean, “Gas spectroscopy and optical path-length assessment in scattering media using a frequency-modulated continuous-wave diode laser,” Opt. Lett. 36(16), 3036–3038 (2011).
[Crossref] [PubMed]

2010 (3)

T. Svensson, E. Alerstam, J. Johansson, and S. Andersson-Engels, “Optical porosimetry and investigations of the porosity experienced by light interacting with porous media,” Opt. Lett. 35(11), 1740–1742 (2010).
[Crossref] [PubMed]

T. Svensson, M. Lewander, and S. Svanberg, “Laser absorption spectroscopy of water vapor confined in nanoporous alumina: wall collision line broadening and gas diffusion dynamics,” Opt. Express 18(16), 16460–16473 (2010).
[Crossref] [PubMed]

T. Svensson and Z. J. Shen, “Laser spectroscopy of gas confined in nanoporous materials,” Appl. Phys. Lett. 96(2), 021107 (2010).
[Crossref]

2009 (3)

T. Svensson, E. Alerstam, D. Khoptyar, J. Johansson, S. Folestad, and S. Andersson-Engels, “Near-infrared photon time-of-flight spectroscopy of turbid materials up to 1400 nm,” Rev. Sci. Instrum. 80(6), 063105 (2009).
[Crossref] [PubMed]

S. J. Erickson and A. Godavarty, “Hand-held based near-infrared optical imaging devices: A review,” Med. Eng. Phys. 31(5), 495–509 (2009).
[Crossref] [PubMed]

M. Lewander, Z. G. Guan, K. Svanberg, S. Svanberg, and T. Svensson, “Clinical system for non-invasive in situ monitoring of gases in the human paranasal sinuses,” Opt. Express 17(13), 10849–10863 (2009).
[Crossref] [PubMed]

2008 (2)

M. Lewander, Z. G. Guan, L. Persson, A. Olsson, and S. Svanberg, “Food monitoring based on diode laser gas spectroscopy,” Appl. Phys. B 93(2-3), 619–625 (2008).
[Crossref]

T. Svensson, M. Andersson, L. Rippe, S. Svanberg, S. Andersson-Engels, J. Johansson, and S. Folestad, “VCSEL-based oxygen spectroscopy for structural analysis of pharmaceutical solids,” Appl. Phys. B 90(2), 345–354 (2008).
[Crossref]

2007 (5)

M. Andersson, L. Persson, T. Svensson, and S. Svanberg, “Flexible lock-in detection system based on synchronized computer plug-in boards applied in sensitive gas spectroscopy,” Rev. Sci. Instrum. 78(11), 113107 (2007).
[Crossref] [PubMed]

S. N. Kasarova, N. G. Sultanova, C. D. Ivanov, and I. D. Nikolov, “Analysis of the dispersion of optical plastic materials,” Opt. Mater. 29(11), 1481–1490 (2007).
[Crossref]

A. Da Silva and S. Kyriakides, “Compressive response and failure of balsa wood,” Int. J. Solids Struct. 44(25-26), 8685–8717 (2007).
[Crossref]

K. Yoshitani, M. Kawaguchi, T. Okuno, T. Kanoda, Y. Ohnishi, M. Kuro, and M. Nishizawa, “Measurements of optical pathlength using phase-resolved spectroscopy in patients undergoing cardiopulmonary bypass,” Anesth. Analg. 104(2), 341–346 (2007).
[Crossref] [PubMed]

P. C. Kamat, C. B. Roller, K. Namjou, J. D. Jeffers, A. Faramarzalian, R. Salas, and P. J. McCann, “Measurement of acetaldehyde in exhaled breath using a laser absorption spectrometer,” Appl. Opt. 46(19), 3969–3975 (2007).
[Crossref] [PubMed]

2006 (3)

M. Andersson, L. Persson, M. Sjöholm, and S. Svanberg, “Spectroscopic studies of wood-drying processes,” Opt. Express 14(8), 3641–3653 (2006).
[Crossref] [PubMed]

A. G. Hendricks, U. Vandsburger, W. R. Saunders, and W. T. Baumann, “The use of tunable diode laser absorption spectroscopy for the measurement of flame dynamics,” Meas. Sci. Technol. 17(1), 139–144 (2006).
[Crossref]

R. Coquard and D. Baillis, “Modeling of heat transfer in low-density EPS foams,” J. Heat Trans. 128(6), 538–549 (2006).
[Crossref]

2005 (2)

A. Puiu, G. Giubileo, and C. Bangrazi, “Laser sensors for trace gases in human breath,” Int. J. Environ. an. Ch. 85(12-13), 1001–1012 (2005).
[Crossref]

G. Somesfalean, J. Alnis, U. Gustafsson, H. Edner, and S. Svanberg, “Long-path monitoring of NO2 with a 635 nm diode laser using frequency-modulation spectroscopy,” Appl. Opt. 44(24), 5148–5151 (2005).
[Crossref] [PubMed]

2003 (2)

J. Alnis, B. Anderson, M. Sjöholm, G. Somesfalean, and S. Svanberg, “Laser spectroscopy of free molecular oxygen dispersed in wood materials,” Appl. Phys. B 77, 691–695 (2003).
[Crossref]

J. G. Rivas, D. H. Dau, A. Imhof, R. Sprik, B. P. J. Bret, P. M. Johnson, T. W. Hijmans, and A. Lagendijk, “Experimental determination of the effective refractive index in strongly scattering media,” Opt. Commun. 220(1-3), 17–21 (2003).
[Crossref]

2002 (3)

T. Fernholz, H. Teichert, and V. Ebert, “Digital, phase-sensitive detection for in situ diode-laser spectroscopy under rapidly changing transmission conditions,” Appl. Phys. B 75(2-3), 229–236 (2002).
[Crossref]

Z. G. Sun, Y. Q. Huang, and E. M. Sevick-Muraca, “Precise analysis of frequency domain photon migration measurement for characterization of concentrated colloidal suspensions,” Rev. Sci. Instrum. 73(2), 383–393 (2002).
[Crossref]

G. Somesfalean, M. Sjöholm, J. Alnis, C. Klinteberg, S. Andersson-Engels, and S. Svanberg, “Concentration measurement of gas embedded in scattering media by employing absorption and time-resolved laser spectroscopy,” Appl. Opt. 41(18), 3538–3544 (2002).
[Crossref] [PubMed]

2001 (2)

S. P. Morgan and K. Y. Yong, “Elimination of amplitude-phase crosstalk in frequency domain near-infrared spectroscopy,” Rev. Sci. Instrum. 72(4), 1984–1987 (2001).
[Crossref]

M. Sjöholm, G. Somesfalean, J. Alnis, S. Andersson-Engels, and S. Svanberg, “Analysis of gas dispersed in scattering media,” Opt. Lett. 26(1), 16–18 (2001).
[Crossref] [PubMed]

2000 (1)

K. Alford and Y. Wickramasinghe, “Phase-amplitude crosstalk in intensity modulated near infrared spectroscopy,” Rev. Sci. Instrum. 71(5), 2191–2195 (2000).
[Crossref]

1999 (1)

P. Kluczynski and O. Axner, “Theoretical description based on Fourier analysis of wavelength-modulation spectrometry in terms of analytical and background signals,” Appl. Opt. 38(27), 5803–5815 (1999).
[Crossref] [PubMed]

1998 (3)

N. Ramanujam, C. Du, H. Y. Ma, and B. Chance, “Sources of phase noise in homodyne and heterodyne phase modulation devices used for tissue oximetry studies,” Rev. Sci. Instrum. 69(8), 3042–3054 (1998).
[Crossref]

B. Chance, M. Cope, E. Gratton, N. Ramanujam, and B. Tromberg, “Phase measurement of light absorption and scatter in human tissue,” Rev. Sci. Instrum. 69(10), 3457–3481 (1998).
[Crossref]

P. Werle, “A review of recent advances in semiconductor laser based gas monitors,” Spectrochim. Acta [A] 54(2), 197–236 (1998).
[Crossref]

1997 (4)

Y. S. Yang, H. L. Liu, X. D. Li, and B. Chance, “Low-cost frequency-domain photon migration instrument for tissue spectroscopy, oximetry, and imaging,” Opt. Eng. 36(5), 1562–1569 (1997).
[Crossref]

B. J. Tromberg, O. Coquoz, J. B. Fishkin, T. Pham, E. R. Anderson, J. Butler, M. Cahn, J. D. Gross, V. Venugopalan, and D. Pham, “Non-invasive measurements of breast tissue optical properties using frequency-domain photon migration,” Philos. Trans. R. Soc. Lond. B Biol. Sci. 352(1354), 661–668 (1997).
[Crossref] [PubMed]

M. Yamauchi, Y. Yamada, and Y. Hasegawa, “Frequency-domain measurements of diffusing photon propagation in solid phantoms,” Opt. Rev. 4(5), 620–621 (1997).
[Crossref]

D. Contini, F. Martelli, and G. Zaccanti, “Photon migration through a turbid slab described by a model based on diffusion approximation. I. Theory,” Appl. Opt. 36(19), 4587–4599 (1997).
[Crossref] [PubMed]

1996 (2)

R. G. Daniel, K. L. McNesby, and A. W. Miziolek, “Application of tunable diode laser diagnostics for temperature and species concentration profiles of inhibited low-pressure flames,” Appl. Opt. 35(21), 4018–4025 (1996).
[Crossref] [PubMed]

H. Fischer, P. Bergamaschi, F. G. Wienhold, T. Zenker, and G. W. Harris, “Development and application of multi-laser TDLAS-instruments for groundbased, shipboard and airborne measurements of trace gas species in the atmosphere,” SPIE 2834, 130–141 (1996).
[Crossref]

1995 (1)

J. Carlsson, P. Hellentin, L. Malmqvist, A. Persson, W. Persson, and C. G. Wahlström, “Time-resolved studies of light propagation in paper,” Appl. Opt. 34(9), 1528–1535 (1995).
[Crossref] [PubMed]

1992 (1)

S. R. Arridge, M. Cope, and D. T. Delpy, “The theoretical basis for the determination of optical pathlengths in tissue - temporal and frequency analysis,” Phys. Med. Biol. 37(7), 1531–1560 (1992).
[Crossref] [PubMed]

1984 (1)

G. Jönsson, C. Levinson, and S. Svanberg, “Natural radiative lifetimes and Stark-shift parameters in the 4p2 configuration in Ca I,” Phys. Scr. 30(1), 65–69 (1984).
[Crossref]

1966 (1)

J. K. Link, “Measurement of radiative lifetimes of first excited states of Na, K, Rb, and Cs by means of phase-shift method,” J. Opt. Soc. Am. 56(9), 1195–1199 (1966).
[Crossref]

Adolfsson, E.

Alerstam, E.

Alford, K.

K. Alford and Y. Wickramasinghe, “Phase-amplitude crosstalk in intensity modulated near infrared spectroscopy,” Rev. Sci. Instrum. 71(5), 2191–2195 (2000).
[Crossref]

Alnis, J.

J. Alnis, B. Anderson, M. Sjöholm, G. Somesfalean, and S. Svanberg, “Laser spectroscopy of free molecular oxygen dispersed in wood materials,” Appl. Phys. B 77, 691–695 (2003).
[Crossref]

M. Sjöholm, G. Somesfalean, J. Alnis, S. Andersson-Engels, and S. Svanberg, “Analysis of gas dispersed in scattering media,” Opt. Lett. 26(1), 16–18 (2001).
[Crossref] [PubMed]

Anderson, B.

J. Alnis, B. Anderson, M. Sjöholm, G. Somesfalean, and S. Svanberg, “Laser spectroscopy of free molecular oxygen dispersed in wood materials,” Appl. Phys. B 77, 691–695 (2003).
[Crossref]

Anderson, E. R.

Andersson, M.

M. Andersson, L. Persson, M. Sjöholm, and S. Svanberg, “Spectroscopic studies of wood-drying processes,” Opt. Express 14(8), 3641–3653 (2006).
[Crossref] [PubMed]

Andersson-Engels, S.

M. Sjöholm, G. Somesfalean, J. Alnis, S. Andersson-Engels, and S. Svanberg, “Analysis of gas dispersed in scattering media,” Opt. Lett. 26(1), 16–18 (2001).
[Crossref] [PubMed]

Arridge, S. R.

Axner, O.

Baillis, D.

R. Coquard and D. Baillis, “Modeling of heat transfer in low-density EPS foams,” J. Heat Trans. 128(6), 538–549 (2006).
[Crossref]

Bangrazi, C.

A. Puiu, G. Giubileo, and C. Bangrazi, “Laser sensors for trace gases in human breath,” Int. J. Environ. an. Ch. 85(12-13), 1001–1012 (2005).
[Crossref]

Baumann, W. T.

Bergamaschi, P.

Bret, B. P. J.

Butler, J.

Cahn, M.

Carlsson, J.

Chance, B.

B. Chance, M. Cope, E. Gratton, N. Ramanujam, and B. Tromberg, “Phase measurement of light absorption and scatter in human tissue,” Rev. Sci. Instrum. 69(10), 3457–3481 (1998).
[Crossref]

Contini, D.

Cope, M.

B. Chance, M. Cope, E. Gratton, N. Ramanujam, and B. Tromberg, “Phase measurement of light absorption and scatter in human tissue,” Rev. Sci. Instrum. 69(10), 3457–3481 (1998).
[Crossref]

Coquard, R.

R. Coquard and D. Baillis, “Modeling of heat transfer in low-density EPS foams,” J. Heat Trans. 128(6), 538–549 (2006).
[Crossref]

Coquoz, O.

Da Silva, A.

A. Da Silva and S. Kyriakides, “Compressive response and failure of balsa wood,” Int. J. Solids Struct. 44(25-26), 8685–8717 (2007).
[Crossref]

Daniel, R. G.

Dau, D. H.

Delpy, D. T.

Du, C.

Ebert, V.

Edner, H.

Erickson, S. J.

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Anesth. Analg. (1)

Appl. Opt. (7)

Appl. Phys. B (5)

J. Alnis, B. Anderson, M. Sjöholm, G. Somesfalean, and S. Svanberg, “Laser spectroscopy of free molecular oxygen dispersed in wood materials,” Appl. Phys. B 77, 691–695 (2003).
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Appl. Phys. Lett. (1)

T. Svensson and Z. J. Shen, “Laser spectroscopy of gas confined in nanoporous materials,” Appl. Phys. Lett. 96(2), 021107 (2010).
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Int. J. Environ. an. Ch. (1)

A. Puiu, G. Giubileo, and C. Bangrazi, “Laser sensors for trace gases in human breath,” Int. J. Environ. an. Ch. 85(12-13), 1001–1012 (2005).
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A. Da Silva and S. Kyriakides, “Compressive response and failure of balsa wood,” Int. J. Solids Struct. 44(25-26), 8685–8717 (2007).
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Meas. Sci. Technol. (1)

Med. Eng. Phys. (1)

S. J. Erickson and A. Godavarty, “Hand-held based near-infrared optical imaging devices: A review,” Med. Eng. Phys. 31(5), 495–509 (2009).
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Opt. Commun. (1)

Opt. Eng. (1)

Opt. Express (3)

M. Andersson, L. Persson, M. Sjöholm, and S. Svanberg, “Spectroscopic studies of wood-drying processes,” Opt. Express 14(8), 3641–3653 (2006).
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Opt. Lett. (3)

M. Sjöholm, G. Somesfalean, J. Alnis, S. Andersson-Engels, and S. Svanberg, “Analysis of gas dispersed in scattering media,” Opt. Lett. 26(1), 16–18 (2001).
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Opt. Mater. (1)

S. N. Kasarova, N. G. Sultanova, C. D. Ivanov, and I. D. Nikolov, “Analysis of the dispersion of optical plastic materials,” Opt. Mater. 29(11), 1481–1490 (2007).
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Opt. Rev. (1)

M. Yamauchi, Y. Yamada, and Y. Hasegawa, “Frequency-domain measurements of diffusing photon propagation in solid phantoms,” Opt. Rev. 4(5), 620–621 (1997).
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Philos. Trans. R. Soc. Lond. B Biol. Sci. (1)

Phys. Med. Biol. (1)

Phys. Rev. Lett. (1)

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B. Chance, M. Cope, E. Gratton, N. Ramanujam, and B. Tromberg, “Phase measurement of light absorption and scatter in human tissue,” Rev. Sci. Instrum. 69(10), 3457–3481 (1998).
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Fig. 1 Setup scheme: the rectangular dotted components are for the FDPM measurements and the rectangular rounded components are for the GASMAS measurements. The two subsystems can be switched manually.

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Fig. 2 Measurement geometry and parameters illustration of the extrapolated boundary condition.

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Fig. 3 Simulation results: Phase shift vs modulation frequency (dot); _{$Δ ϕ' = 2 π f_{0} L_{m} / c$} (dashed line). The optical properties used in the simulation (_{$μ_{s}'$} = 3410, _{$μ_{a}$} = 0.17 and _{$n_{s m}$} = 1.01) are typical values for PS foam. The sample thickness is 30 mm, and the source-detector separation (_$ξ$) is 0.

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Fig. 4 Recorded raw signals: the reference signal is sampled from the RF source directly, the instrument response is detected without any sample, while the scattered light signal is detected after the sample.

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Fig. 5 Recorded phase shifts at 5, 10, 20, 30, 40 and 50 MHz modulation frequency for PS foams. The dashed lines are the fittings of the recorded phase shifts, _{$n_{s m}$} = 1.01.

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Fig. 6 Recorded phase shifts at 5, 10, 20, 30, 40 and 50 MHz modulation frequency for balsa (10.3 mm) and spruce (8.6 mm) wood samples. The dashed lines are the fittings of the recorded phase shifts, _{$n_{s m}$} = 1.40.

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Tables (3)

Table 1 Optical properties and the MOPL of PS foam samples as calculated from the fitting procedure and by using a 10-MHz modulation frequency, $n_{s m}$ =1.01.

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Table 2 Path lengths through the gas-filled pores ( $L_{g a s}$ ), physical path lengths ( $L_{p h y s i c a l}$ ) through the medium, as well as optical and physical porosities of PS foams, $n_{s o l i d}$ = 1.58.

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Table 3 Optical properties, MOPLs, path lengths through the gas-filled pores ( $L_{g a s}$ ), physical path lengths ( $L_{p h y s i c a l}$ ) through the medium, optical and physical porosities of a balsa (10.3 mm) and a spruce (8.6 mm) samples, $n_{s m}$ = 1.40 and $n_{s o l i d}$ = 1.47.

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Equations (9)

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G_{s l a b} (ξ, z_{0}, f_{0}, t') = \frac{- e^{- i 2 π f_{0} t'}}{{(2 π)}^{3 / 2}} \sum_{m = - \infty}^{\infty} [\frac{(d - z_{+ m})}{ρ_{+ m}^{3}} (1 + α ρ_{+ m}) e^{- α ρ_{+ m}} - \frac{(d - z_{- m})}{ρ_{- m}^{3}} (1 + α ρ_{- m}) e^{- α ρ_{- m}}] .

{\begin{cases} z_{+, m} = 2 m d + 4 m z_{b} + z_{0} \\ z_{-, m} = 2 m d + (4 m - 2) z_{b} - z_{0} \end{cases},

ρ_{\pm m} = \sqrt{ξ^{2} + {(d - z_{\pm, m})}^{2}},

α = \sqrt{(μ_{a} c' + i 2 π f_{0}) / D c'} .

\begin{array}{l} T (τ) = \frac{c'}{2} (^{4 π D) - 3 / 2} (^{c' τ) - 5 / 2} \exp (- μ_{a} c' τ) \exp (\frac{- ξ^{2}}{4 D c' τ}) \\ \sum_{m = - \infty}^{+ \infty} {(d - z_{+, m}) \exp [- \frac{{(d - z_{+, m})}^{2}}{4 D c' τ}] - (d - z_{-, m}) \exp [- \frac{{(d - z_{-, m})}^{2}}{4 D c' τ}]} . \end{array}

L_{m} = n_{s m} c' \int T (τ) τ d τ / \int T (τ) τ d τ .

Δ ϕ' = 2 π f_{0} L_{m} / c .

S (t) = p_{0} + p_{1} t + p_{2} t^{2} + χ S_{r e f} (t - t_{0}) .

L_{p h y s i c a l} = L_{g a s} + (L_{m} - L_{g a s}) / n_{s o l i d} .

Sample thickness (_{$m m$})	19	24	29	35	39
_{$μ_{s}'$}(_{$c m^{- 1}$})	39.0	34.0	30.4	35.2	31.8
_{$μ_{a}$}(_{$c m^{- 1}$})	0.03	0.00	0.00	0.00	0.00
MOPL – fitting (_{$c m$})	36	74	96	156	182
MOPL @ 10 MHz (_{$c m$})	36	74	96	154	179

	_{$μ_{s}'$}(_{$c m^{- 1}$})	_{$μ_{a}$}(_{$c m^{- 1}$})	MOPL -fitting (_{$c m$})	MOPL@ 10 MHz (_{$c m$})	_{$L_{g a s}$} (_{$c m$})	_{$L_{p h y s i c a l}$} (_{$c m$})	Optical porosity (%)	Physical porosity (%)
Balsa	35.1	0.01	22	22	11	19	58	92
Spruce	69.9	0.00	29	30	8	22	36	67

Sample thickness (_{$m m$})	19	24	29	35	39
_{$μ_{s}'$}(_{$c m^{- 1}$})	39.0	34.0	30.4	35.2	31.8
_{$μ_{a}$}(_{$c m^{- 1}$})	0.03	0.00	0.00	0.00	0.00
MOPL – fitting (_{$c m$})	36	74	96	156	182
MOPL @ 10 MHz (_{$c m$})	36	74	96	154	179

	_{$μ_{s}'$}(_{$c m^{- 1}$})	_{$μ_{a}$}(_{$c m^{- 1}$})	MOPL -fitting (_{$c m$})	MOPL@ 10 MHz (_{$c m$})	_{$L_{g a s}$} (_{$c m$})	_{$L_{p h y s i c a l}$} (_{$c m$})	Optical porosity (%)	Physical porosity (%)
Balsa	35.1	0.01	22	22	11	19	58	92
Spruce	69.9	0.00	29	30	8	22	36	67

Sample thickness (_{$m m$})	19	24	29	35	39
_{$L_{g a s}$}(_{$c m$})	36	71	94	145	169
_{$L_{p h y s i c a l}$}(_{$c m$})	36	73	95	152	177
Optical porosity (%)	100	97	99	95	95
Physical porosity (%)	98	98	98	98	98