Abstract

Spectral depth-profiling of optically turbid samples is of high interest to a broad range of applications. We present a method for measuring spatially-offset Raman spectroscopy (SORS) over a range of length scales by incorporating a digital micro-mirror device (DMD) into a sample-conjugate plane in the detection optical path. The DMD can be arbitrarily programmed to collect/reject light at spatial positions in the 2D sample-conjugate plane, allowing spatially offset Raman measurements. We demonstrate several detection geometries, including annular and simultaneous multi-offset modalities, for both macro- and micro-SORS measurements, all on the same instrument. Compared to other SORS modalities, DMD-based SORS provides more flexibility with only minimal additional experimental complexity for subsurface Raman collection.

Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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References

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    [Crossref]
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    [Crossref]
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    [Crossref] [PubMed]

2016 (2)

P. Matousek and N. Stone, “Development of deep subsurface Raman spectroscopy for medical diagnosis and disease monitoring,” Chem. Soc. Rev. 45(7), 1794–1802 (2016).
[Crossref] [PubMed]

J. Qin, M. S. Kim, W. F. Schmidt, B.-K. Cho, Y. Peng, and K. Chao, “A line-scan hyperspectral Raman system for spatially offset Raman spectroscopy,” J. Raman Spectrosc. 47(4), 437–443 (2016).
[Crossref]

2015 (4)

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

C. Conti, C. Colombo, M. Realini, and P. Matousek, “Subsurface analysis of painted sculptures and plasters using micrometre-scale spatially offset Raman spectroscopy (micro-SORS),” J. Raman Spectrosc. 46(5), 476–482 (2015).
[Crossref]

C. Conti, M. Realini, C. Colombo, and P. Matousek, “Comparison of key modalities of micro-scale spatially offset Raman spectroscopy,” Analyst (Lond.) 140(24), 8127–8133 (2015).
[Crossref] [PubMed]

J.-L. H. Demers, F. W. L. Esmonde-White, K. A. Esmonde-White, M. D. Morris, and B. W. Pogue, “Next-generation Raman tomography instrument for non-invasive in vivo bone imaging,” Biomed. Opt. Express 6(3), 793–806 (2015).
[Crossref] [PubMed]

2014 (1)

2013 (3)

G. M. Gibson, M. Dienerowitz, P. A. Kelleher, A. R. Harvey, and M. J. Padgett, “A multi-object spectral imaging instrument,” J. Opt. 15(8), 085302 (2013).
[Crossref]

M. Bloomfield, D. Andrews, P. Loeffen, C. Tombling, T. York, and P. Matousek, “Non-invasive identification of incoming raw pharmaceutical materials using Spatially Offset Raman Spectroscopy,” J. Pharm. Biomed. Anal. 76, 65–69 (2013).
[Crossref] [PubMed]

B. Sharma, K. Ma, M. R. Glucksberg, and R. P. Van Duyne, “Seeing through bone with surface-enhanced spatially offset Raman spectroscopy,” J. Am. Chem. Soc. 135(46), 17290–17293 (2013).
[Crossref] [PubMed]

2011 (3)

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

D. T. Yang and Y. B. Ying, “Applications of Raman spectroscopy in agricultural products and food analysis: a review,” Appl. Spectrosc. Rev. 46(7), 539–560 (2011).
[Crossref]

W. J. Olds, E. Jaatinen, P. Fredericks, B. Cletus, H. Panayiotou, and E. L. Izake, “Spatially offset Raman spectroscopy (SORS) for the analysis and detection of packaged pharmaceuticals and concealed drugs,” Forensic Sci. Int. 212(1-3), 69–77 (2011).
[Crossref] [PubMed]

2008 (1)

C. Eliasson, N. A. Macleod, and P. Matousek, “Non-invasive detection of cocaine dissolved in beverages using displaced Raman spectroscopy,” Anal. Chim. Acta 607(1), 50–53 (2008).
[Crossref] [PubMed]

2007 (2)

C. Eliasson, N. A. Macleod, and P. Matousek, “Noninvasive detection of concealed liquid explosives using Raman spectroscopy,” Anal. Chem. 79(21), 8185–8189 (2007).
[Crossref] [PubMed]

C. Eliasson and P. Matousek, “Noninvasive authentication of pharmaceutical products through packaging using spatially offset Raman spectroscopy,” Anal. Chem. 79(4), 1696–1701 (2007).
[Crossref] [PubMed]

2006 (2)

2005 (1)

2004 (1)

I. Notingher and R. E. Imhof, “Mid-infrared in vivo depth-profiling of topical chemicals on skin,” Skin Res. Technol. 10(2), 113–121 (2004).
[Crossref] [PubMed]

2003 (2)

W. Faubel, S. Heissler, and R. A. Palmer, “Quantitative analysis of corroded copper patina by step scan and rapid scan photoacoustic Fourier transform infrared spectroscopy,” Rev. Sci. Instrum. 74(1), 331–333 (2003).
[Crossref]

I. Notingher, R. E. Imhof, P. Xiao, and F. C. Pascut, “Spectral depth profiling of arbitrary surfaces by thermal emission decay-Fourier transform infrared spectroscopy,” Appl. Spectrosc. 57(12), 1494–1501 (2003).
[Crossref] [PubMed]

2002 (1)

2001 (1)

P. J. Caspers, G. W. Lucassen, E. A. Carter, H. A. Bruining, and G. J. Puppels, “In vivo confocal Raman microspectroscopy of the skin: noninvasive determination of molecular concentration profiles,” J. Invest. Dermatol. 116(3), 434–442 (2001).
[Crossref] [PubMed]

2000 (2)

1999 (1)

1997 (1)

Afseth, N. K.

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

Allison, C. L.

Andrews, D.

M. Bloomfield, D. Andrews, P. Loeffen, C. Tombling, T. York, and P. Matousek, “Non-invasive identification of incoming raw pharmaceutical materials using Spatially Offset Raman Spectroscopy,” J. Pharm. Biomed. Anal. 76, 65–69 (2013).
[Crossref] [PubMed]

Bertasa, M.

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

Bi, X.

Bloomfield, M.

M. Bloomfield, D. Andrews, P. Loeffen, C. Tombling, T. York, and P. Matousek, “Non-invasive identification of incoming raw pharmaceutical materials using Spatially Offset Raman Spectroscopy,” J. Pharm. Biomed. Anal. 76, 65–69 (2013).
[Crossref] [PubMed]

Botteon, A.

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

C. Conti, M. Realini, C. Colombo, A. Botteon, and P. Matousek, “Contrasting confocal with defocusing microscale spatially offset Raman spectroscopy,” J. Raman Spectrosc.in press.

Bruining, H. A.

P. J. Caspers, G. W. Lucassen, E. A. Carter, H. A. Bruining, and G. J. Puppels, “In vivo confocal Raman microspectroscopy of the skin: noninvasive determination of molecular concentration profiles,” J. Invest. Dermatol. 116(3), 434–442 (2001).
[Crossref] [PubMed]

Carter, E. A.

P. J. Caspers, G. W. Lucassen, E. A. Carter, H. A. Bruining, and G. J. Puppels, “In vivo confocal Raman microspectroscopy of the skin: noninvasive determination of molecular concentration profiles,” J. Invest. Dermatol. 116(3), 434–442 (2001).
[Crossref] [PubMed]

Caspers, P. J.

P. J. Caspers, G. W. Lucassen, E. A. Carter, H. A. Bruining, and G. J. Puppels, “In vivo confocal Raman microspectroscopy of the skin: noninvasive determination of molecular concentration profiles,” J. Invest. Dermatol. 116(3), 434–442 (2001).
[Crossref] [PubMed]

Chao, K.

J. Qin, M. S. Kim, W. F. Schmidt, B.-K. Cho, Y. Peng, and K. Chao, “A line-scan hyperspectral Raman system for spatially offset Raman spectroscopy,” J. Raman Spectrosc. 47(4), 437–443 (2016).
[Crossref]

Cho, B.-K.

J. Qin, M. S. Kim, W. F. Schmidt, B.-K. Cho, Y. Peng, and K. Chao, “A line-scan hyperspectral Raman system for spatially offset Raman spectroscopy,” J. Raman Spectrosc. 47(4), 437–443 (2016).
[Crossref]

Clark, I. P.

Cletus, B.

W. J. Olds, E. Jaatinen, P. Fredericks, B. Cletus, H. Panayiotou, and E. L. Izake, “Spatially offset Raman spectroscopy (SORS) for the analysis and detection of packaged pharmaceuticals and concealed drugs,” Forensic Sci. Int. 212(1-3), 69–77 (2011).
[Crossref] [PubMed]

Colombo, C.

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

C. Conti, C. Colombo, M. Realini, and P. Matousek, “Subsurface analysis of painted sculptures and plasters using micrometre-scale spatially offset Raman spectroscopy (micro-SORS),” J. Raman Spectrosc. 46(5), 476–482 (2015).
[Crossref]

C. Conti, M. Realini, C. Colombo, and P. Matousek, “Comparison of key modalities of micro-scale spatially offset Raman spectroscopy,” Analyst (Lond.) 140(24), 8127–8133 (2015).
[Crossref] [PubMed]

C. Conti, M. Realini, C. Colombo, A. Botteon, and P. Matousek, “Contrasting confocal with defocusing microscale spatially offset Raman spectroscopy,” J. Raman Spectrosc.in press.

Conti, C.

C. Conti, M. Realini, C. Colombo, and P. Matousek, “Comparison of key modalities of micro-scale spatially offset Raman spectroscopy,” Analyst (Lond.) 140(24), 8127–8133 (2015).
[Crossref] [PubMed]

C. Conti, C. Colombo, M. Realini, and P. Matousek, “Subsurface analysis of painted sculptures and plasters using micrometre-scale spatially offset Raman spectroscopy (micro-SORS),” J. Raman Spectrosc. 46(5), 476–482 (2015).
[Crossref]

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

C. Conti, M. Realini, C. Colombo, A. Botteon, and P. Matousek, “Contrasting confocal with defocusing microscale spatially offset Raman spectroscopy,” J. Raman Spectrosc.in press.

de Matos Granja, N.

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

Demers, J.-L. H.

Di Stefano, F.

Dienerowitz, M.

G. M. Gibson, M. Dienerowitz, P. A. Kelleher, A. R. Harvey, and M. J. Padgett, “A multi-object spectral imaging instrument,” J. Opt. 15(8), 085302 (2013).
[Crossref]

Ding, H.

Draper, E. R. C.

Ekgasit, S.

Eliasson, C.

C. Eliasson, N. A. Macleod, and P. Matousek, “Non-invasive detection of cocaine dissolved in beverages using displaced Raman spectroscopy,” Anal. Chim. Acta 607(1), 50–53 (2008).
[Crossref] [PubMed]

C. Eliasson, N. A. Macleod, and P. Matousek, “Noninvasive detection of concealed liquid explosives using Raman spectroscopy,” Anal. Chem. 79(21), 8185–8189 (2007).
[Crossref] [PubMed]

C. Eliasson and P. Matousek, “Noninvasive authentication of pharmaceutical products through packaging using spatially offset Raman spectroscopy,” Anal. Chem. 79(4), 1696–1701 (2007).
[Crossref] [PubMed]

Esmonde-White, F. W. L.

Esmonde-White, K. A.

Everall, N.

Everall, N. J.

Faubel, W.

W. Faubel, S. Heissler, and R. A. Palmer, “Quantitative analysis of corroded copper patina by step scan and rapid scan photoacoustic Fourier transform infrared spectroscopy,” Rev. Sci. Instrum. 74(1), 331–333 (2003).
[Crossref]

Finney, W. F.

Fredericks, P.

W. J. Olds, E. Jaatinen, P. Fredericks, B. Cletus, H. Panayiotou, and E. L. Izake, “Spatially offset Raman spectroscopy (SORS) for the analysis and detection of packaged pharmaceuticals and concealed drugs,” Forensic Sci. Int. 212(1-3), 69–77 (2011).
[Crossref] [PubMed]

Gibson, G. M.

G. M. Gibson, M. Dienerowitz, P. A. Kelleher, A. R. Harvey, and M. J. Padgett, “A multi-object spectral imaging instrument,” J. Opt. 15(8), 085302 (2013).
[Crossref]

Glucksberg, M. R.

B. Sharma, K. Ma, M. R. Glucksberg, and R. P. Van Duyne, “Seeing through bone with surface-enhanced spatially offset Raman spectroscopy,” J. Am. Chem. Soc. 135(46), 17290–17293 (2013).
[Crossref] [PubMed]

Goodship, A. E.

Harvey, A. R.

G. M. Gibson, M. Dienerowitz, P. A. Kelleher, A. R. Harvey, and M. J. Padgett, “A multi-object spectral imaging instrument,” J. Opt. 15(8), 085302 (2013).
[Crossref]

Heissler, S.

W. Faubel, S. Heissler, and R. A. Palmer, “Quantitative analysis of corroded copper patina by step scan and rapid scan photoacoustic Fourier transform infrared spectroscopy,” Rev. Sci. Instrum. 74(1), 331–333 (2003).
[Crossref]

Imhof, R. E.

Ishida, H.

Izake, E. L.

W. J. Olds, E. Jaatinen, P. Fredericks, B. Cletus, H. Panayiotou, and E. L. Izake, “Spatially offset Raman spectroscopy (SORS) for the analysis and detection of packaged pharmaceuticals and concealed drugs,” Forensic Sci. Int. 212(1-3), 69–77 (2011).
[Crossref] [PubMed]

Jaatinen, E.

W. J. Olds, E. Jaatinen, P. Fredericks, B. Cletus, H. Panayiotou, and E. L. Izake, “Spatially offset Raman spectroscopy (SORS) for the analysis and detection of packaged pharmaceuticals and concealed drugs,” Forensic Sci. Int. 212(1-3), 69–77 (2011).
[Crossref] [PubMed]

Johnson, G. L.

Jones, R. W.

Kelleher, P. A.

G. M. Gibson, M. Dienerowitz, P. A. Kelleher, A. R. Harvey, and M. J. Padgett, “A multi-object spectral imaging instrument,” J. Opt. 15(8), 085302 (2013).
[Crossref]

Keller, M. D.

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

Kelley, M. C.

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

Kim, M. S.

J. Qin, M. S. Kim, W. F. Schmidt, B.-K. Cho, Y. Peng, and K. Chao, “A line-scan hyperspectral Raman system for spatially offset Raman spectroscopy,” J. Raman Spectrosc. 47(4), 437–443 (2016).
[Crossref]

Loeffen, P.

M. Bloomfield, D. Andrews, P. Loeffen, C. Tombling, T. York, and P. Matousek, “Non-invasive identification of incoming raw pharmaceutical materials using Spatially Offset Raman Spectroscopy,” J. Pharm. Biomed. Anal. 76, 65–69 (2013).
[Crossref] [PubMed]

Lu, G.

Lucassen, G. W.

P. J. Caspers, G. W. Lucassen, E. A. Carter, H. A. Bruining, and G. J. Puppels, “In vivo confocal Raman microspectroscopy of the skin: noninvasive determination of molecular concentration profiles,” J. Invest. Dermatol. 116(3), 434–442 (2001).
[Crossref] [PubMed]

Ma, K.

B. Sharma, K. Ma, M. R. Glucksberg, and R. P. Van Duyne, “Seeing through bone with surface-enhanced spatially offset Raman spectroscopy,” J. Am. Chem. Soc. 135(46), 17290–17293 (2013).
[Crossref] [PubMed]

Macleod, N. A.

C. Eliasson, N. A. Macleod, and P. Matousek, “Non-invasive detection of cocaine dissolved in beverages using displaced Raman spectroscopy,” Anal. Chim. Acta 607(1), 50–53 (2008).
[Crossref] [PubMed]

C. Eliasson, N. A. Macleod, and P. Matousek, “Noninvasive detection of concealed liquid explosives using Raman spectroscopy,” Anal. Chem. 79(21), 8185–8189 (2007).
[Crossref] [PubMed]

Mahadevan-Jansen, A.

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

Matousek, P.

P. Matousek and N. Stone, “Development of deep subsurface Raman spectroscopy for medical diagnosis and disease monitoring,” Chem. Soc. Rev. 45(7), 1794–1802 (2016).
[Crossref] [PubMed]

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

C. Conti, C. Colombo, M. Realini, and P. Matousek, “Subsurface analysis of painted sculptures and plasters using micrometre-scale spatially offset Raman spectroscopy (micro-SORS),” J. Raman Spectrosc. 46(5), 476–482 (2015).
[Crossref]

C. Conti, M. Realini, C. Colombo, and P. Matousek, “Comparison of key modalities of micro-scale spatially offset Raman spectroscopy,” Analyst (Lond.) 140(24), 8127–8133 (2015).
[Crossref] [PubMed]

M. Bloomfield, D. Andrews, P. Loeffen, C. Tombling, T. York, and P. Matousek, “Non-invasive identification of incoming raw pharmaceutical materials using Spatially Offset Raman Spectroscopy,” J. Pharm. Biomed. Anal. 76, 65–69 (2013).
[Crossref] [PubMed]

C. Eliasson, N. A. Macleod, and P. Matousek, “Non-invasive detection of cocaine dissolved in beverages using displaced Raman spectroscopy,” Anal. Chim. Acta 607(1), 50–53 (2008).
[Crossref] [PubMed]

C. Eliasson, N. A. Macleod, and P. Matousek, “Noninvasive detection of concealed liquid explosives using Raman spectroscopy,” Anal. Chem. 79(21), 8185–8189 (2007).
[Crossref] [PubMed]

C. Eliasson and P. Matousek, “Noninvasive authentication of pharmaceutical products through packaging using spatially offset Raman spectroscopy,” Anal. Chem. 79(4), 1696–1701 (2007).
[Crossref] [PubMed]

P. Matousek, “Inverse spatially offset Raman spectroscopy for deep noninvasive probing of turbid media,” Appl. Spectrosc. 60(11), 1341–1347 (2006).
[Crossref] [PubMed]

P. Matousek, E. R. C. Draper, A. E. Goodship, I. P. Clark, K. L. Ronayne, and A. W. Parker, “Noninvasive Raman spectroscopy of human tissue in vivo,” Appl. Spectrosc. 60(7), 758–763 (2006).
[Crossref] [PubMed]

P. Matousek, I. P. Clark, E. R. C. Draper, M. D. Morris, A. E. Goodship, N. Everall, M. Towrie, W. F. Finney, and A. W. Parker, “Subsurface probing in diffusely scattering media using spatially offset Raman spectroscopy,” Appl. Spectrosc. 59(4), 393–400 (2005).
[Crossref] [PubMed]

C. Conti, M. Realini, C. Colombo, A. Botteon, and P. Matousek, “Contrasting confocal with defocusing microscale spatially offset Raman spectroscopy,” J. Raman Spectrosc.in press.

McClelland, J. F.

Morris, M. D.

Mycek, M. A.

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

Notingher, I.

Olds, W. J.

W. J. Olds, E. Jaatinen, P. Fredericks, B. Cletus, H. Panayiotou, and E. L. Izake, “Spatially offset Raman spectroscopy (SORS) for the analysis and detection of packaged pharmaceuticals and concealed drugs,” Forensic Sci. Int. 212(1-3), 69–77 (2011).
[Crossref] [PubMed]

Padgett, M. J.

G. M. Gibson, M. Dienerowitz, P. A. Kelleher, A. R. Harvey, and M. J. Padgett, “A multi-object spectral imaging instrument,” J. Opt. 15(8), 085302 (2013).
[Crossref]

Palmer, R. A.

W. Faubel, S. Heissler, and R. A. Palmer, “Quantitative analysis of corroded copper patina by step scan and rapid scan photoacoustic Fourier transform infrared spectroscopy,” Rev. Sci. Instrum. 74(1), 331–333 (2003).
[Crossref]

Panayiotou, H.

W. J. Olds, E. Jaatinen, P. Fredericks, B. Cletus, H. Panayiotou, and E. L. Izake, “Spatially offset Raman spectroscopy (SORS) for the analysis and detection of packaged pharmaceuticals and concealed drugs,” Forensic Sci. Int. 212(1-3), 69–77 (2011).
[Crossref] [PubMed]

Parker, A. W.

Pascut, F. C.

Peng, Y.

J. Qin, M. S. Kim, W. F. Schmidt, B.-K. Cho, Y. Peng, and K. Chao, “A line-scan hyperspectral Raman system for spatially offset Raman spectroscopy,” J. Raman Spectrosc. 47(4), 437–443 (2016).
[Crossref]

Pogue, B. W.

Puppels, G. J.

P. J. Caspers, G. W. Lucassen, E. A. Carter, H. A. Bruining, and G. J. Puppels, “In vivo confocal Raman microspectroscopy of the skin: noninvasive determination of molecular concentration profiles,” J. Invest. Dermatol. 116(3), 434–442 (2001).
[Crossref] [PubMed]

Qin, J.

J. Qin, M. S. Kim, W. F. Schmidt, B.-K. Cho, Y. Peng, and K. Chao, “A line-scan hyperspectral Raman system for spatially offset Raman spectroscopy,” J. Raman Spectrosc. 47(4), 437–443 (2016).
[Crossref]

Realini, M.

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

C. Conti, C. Colombo, M. Realini, and P. Matousek, “Subsurface analysis of painted sculptures and plasters using micrometre-scale spatially offset Raman spectroscopy (micro-SORS),” J. Raman Spectrosc. 46(5), 476–482 (2015).
[Crossref]

C. Conti, M. Realini, C. Colombo, and P. Matousek, “Comparison of key modalities of micro-scale spatially offset Raman spectroscopy,” Analyst (Lond.) 140(24), 8127–8133 (2015).
[Crossref] [PubMed]

C. Conti, M. Realini, C. Colombo, A. Botteon, and P. Matousek, “Contrasting confocal with defocusing microscale spatially offset Raman spectroscopy,” J. Raman Spectrosc.in press.

Ronayne, K. L.

Schmidt, W. F.

J. Qin, M. S. Kim, W. F. Schmidt, B.-K. Cho, Y. Peng, and K. Chao, “A line-scan hyperspectral Raman system for spatially offset Raman spectroscopy,” J. Raman Spectrosc. 47(4), 437–443 (2016).
[Crossref]

Sharma, B.

B. Sharma, K. Ma, M. R. Glucksberg, and R. P. Van Duyne, “Seeing through bone with surface-enhanced spatially offset Raman spectroscopy,” J. Am. Chem. Soc. 135(46), 17290–17293 (2013).
[Crossref] [PubMed]

Sowoidnich, K.

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

Stone, N.

P. Matousek and N. Stone, “Development of deep subsurface Raman spectroscopy for medical diagnosis and disease monitoring,” Chem. Soc. Rev. 45(7), 1794–1802 (2016).
[Crossref] [PubMed]

Tombling, C.

M. Bloomfield, D. Andrews, P. Loeffen, C. Tombling, T. York, and P. Matousek, “Non-invasive identification of incoming raw pharmaceutical materials using Spatially Offset Raman Spectroscopy,” J. Pharm. Biomed. Anal. 76, 65–69 (2013).
[Crossref] [PubMed]

Towrie, M.

Urban, M. W.

Van Duyne, R. P.

B. Sharma, K. Ma, M. R. Glucksberg, and R. P. Van Duyne, “Seeing through bone with surface-enhanced spatially offset Raman spectroscopy,” J. Am. Chem. Soc. 135(46), 17290–17293 (2013).
[Crossref] [PubMed]

Vargis, E.

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

Wang, Z.

Wilson, R. H.

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

Xiao, P.

Yang, D. T.

D. T. Yang and Y. B. Ying, “Applications of Raman spectroscopy in agricultural products and food analysis: a review,” Appl. Spectrosc. Rev. 46(7), 539–560 (2011).
[Crossref]

Ying, Y. B.

D. T. Yang and Y. B. Ying, “Applications of Raman spectroscopy in agricultural products and food analysis: a review,” Appl. Spectrosc. Rev. 46(7), 539–560 (2011).
[Crossref]

York, T.

M. Bloomfield, D. Andrews, P. Loeffen, C. Tombling, T. York, and P. Matousek, “Non-invasive identification of incoming raw pharmaceutical materials using Spatially Offset Raman Spectroscopy,” J. Pharm. Biomed. Anal. 76, 65–69 (2013).
[Crossref] [PubMed]

Anal. Chem. (3)

C. Eliasson, N. A. Macleod, and P. Matousek, “Noninvasive detection of concealed liquid explosives using Raman spectroscopy,” Anal. Chem. 79(21), 8185–8189 (2007).
[Crossref] [PubMed]

C. Eliasson and P. Matousek, “Noninvasive authentication of pharmaceutical products through packaging using spatially offset Raman spectroscopy,” Anal. Chem. 79(4), 1696–1701 (2007).
[Crossref] [PubMed]

C. Conti, M. Realini, C. Colombo, K. Sowoidnich, N. K. Afseth, M. Bertasa, A. Botteon, and P. Matousek, “Noninvasive analysis of thin turbid layers using microscale spatially offset Raman spectroscopy,” Anal. Chem. 87(11), 5810–5815 (2015).
[Crossref] [PubMed]

Anal. Chim. Acta (1)

C. Eliasson, N. A. Macleod, and P. Matousek, “Non-invasive detection of cocaine dissolved in beverages using displaced Raman spectroscopy,” Anal. Chim. Acta 607(1), 50–53 (2008).
[Crossref] [PubMed]

Analyst (Lond.) (1)

C. Conti, M. Realini, C. Colombo, and P. Matousek, “Comparison of key modalities of micro-scale spatially offset Raman spectroscopy,” Analyst (Lond.) 140(24), 8127–8133 (2015).
[Crossref] [PubMed]

Appl. Spectrosc. (9)

P. Matousek, E. R. C. Draper, A. E. Goodship, I. P. Clark, K. L. Ronayne, and A. W. Parker, “Noninvasive Raman spectroscopy of human tissue in vivo,” Appl. Spectrosc. 60(7), 758–763 (2006).
[Crossref] [PubMed]

P. Matousek, I. P. Clark, E. R. C. Draper, M. D. Morris, A. E. Goodship, N. Everall, M. Towrie, W. F. Finney, and A. W. Parker, “Subsurface probing in diffusely scattering media using spatially offset Raman spectroscopy,” Appl. Spectrosc. 59(4), 393–400 (2005).
[Crossref] [PubMed]

I. Notingher, R. E. Imhof, P. Xiao, and F. C. Pascut, “Spectral depth profiling of arbitrary surfaces by thermal emission decay-Fourier transform infrared spectroscopy,” Appl. Spectrosc. 57(12), 1494–1501 (2003).
[Crossref] [PubMed]

P. Matousek, “Inverse spatially offset Raman spectroscopy for deep noninvasive probing of turbid media,” Appl. Spectrosc. 60(11), 1341–1347 (2006).
[Crossref] [PubMed]

R. W. Jones and J. F. McClelland, “Quantitative depth profiling using saturation-equalized photoacoustic spectra,” Appl. Spectrosc. 56(4), 409–418 (2002).
[Crossref]

N. J. Everall, “Confocal Raman microscopy: why the depth resolution and spatial accuracy can be much worse than you think,” Appl. Spectrosc. 54(10), 1515–1520 (2000).
[Crossref]

N. J. Everall, “Modeling and measuring the effect of refraction on the depth resolution of confocal Raman microscopy,” Appl. Spectrosc. 54(6), 773–782 (2000).
[Crossref]

M. W. Urban, C. L. Allison, G. L. Johnson, and F. Di Stefano, “Stratification of butyl acrylate/polyurethane (BA/PUR) latexes: ATR and step-scan photoacoustic studies,” Appl. Spectrosc. 53(12), 1520–1527 (1999).
[Crossref]

S. Ekgasit and H. Ishida, “New optical depth-profiling technique by use of the multiple-frequency approach with single ATR FT-IR spectrum: theoretical development,” Appl. Spectrosc. 51(10), 1488–1495 (1997).
[Crossref]

Appl. Spectrosc. Rev. (1)

D. T. Yang and Y. B. Ying, “Applications of Raman spectroscopy in agricultural products and food analysis: a review,” Appl. Spectrosc. Rev. 46(7), 539–560 (2011).
[Crossref]

Biomed. Opt. Express (1)

Chem. Soc. Rev. (1)

P. Matousek and N. Stone, “Development of deep subsurface Raman spectroscopy for medical diagnosis and disease monitoring,” Chem. Soc. Rev. 45(7), 1794–1802 (2016).
[Crossref] [PubMed]

Forensic Sci. Int. (1)

W. J. Olds, E. Jaatinen, P. Fredericks, B. Cletus, H. Panayiotou, and E. L. Izake, “Spatially offset Raman spectroscopy (SORS) for the analysis and detection of packaged pharmaceuticals and concealed drugs,” Forensic Sci. Int. 212(1-3), 69–77 (2011).
[Crossref] [PubMed]

J. Am. Chem. Soc. (1)

B. Sharma, K. Ma, M. R. Glucksberg, and R. P. Van Duyne, “Seeing through bone with surface-enhanced spatially offset Raman spectroscopy,” J. Am. Chem. Soc. 135(46), 17290–17293 (2013).
[Crossref] [PubMed]

J. Biomed. Opt. (1)

M. D. Keller, E. Vargis, N. de Matos Granja, R. H. Wilson, M. A. Mycek, M. C. Kelley, and A. Mahadevan-Jansen, “Development of a spatially offset Raman spectroscopy probe for breast tumor surgical margin evaluation,” J. Biomed. Opt. 16(7), 077006 (2011).
[Crossref] [PubMed]

J. Invest. Dermatol. (1)

P. J. Caspers, G. W. Lucassen, E. A. Carter, H. A. Bruining, and G. J. Puppels, “In vivo confocal Raman microspectroscopy of the skin: noninvasive determination of molecular concentration profiles,” J. Invest. Dermatol. 116(3), 434–442 (2001).
[Crossref] [PubMed]

J. Opt. (1)

G. M. Gibson, M. Dienerowitz, P. A. Kelleher, A. R. Harvey, and M. J. Padgett, “A multi-object spectral imaging instrument,” J. Opt. 15(8), 085302 (2013).
[Crossref]

J. Pharm. Biomed. Anal. (1)

M. Bloomfield, D. Andrews, P. Loeffen, C. Tombling, T. York, and P. Matousek, “Non-invasive identification of incoming raw pharmaceutical materials using Spatially Offset Raman Spectroscopy,” J. Pharm. Biomed. Anal. 76, 65–69 (2013).
[Crossref] [PubMed]

J. Raman Spectrosc. (2)

C. Conti, C. Colombo, M. Realini, and P. Matousek, “Subsurface analysis of painted sculptures and plasters using micrometre-scale spatially offset Raman spectroscopy (micro-SORS),” J. Raman Spectrosc. 46(5), 476–482 (2015).
[Crossref]

J. Qin, M. S. Kim, W. F. Schmidt, B.-K. Cho, Y. Peng, and K. Chao, “A line-scan hyperspectral Raman system for spatially offset Raman spectroscopy,” J. Raman Spectrosc. 47(4), 437–443 (2016).
[Crossref]

Opt. Lett. (1)

Rev. Sci. Instrum. (1)

W. Faubel, S. Heissler, and R. A. Palmer, “Quantitative analysis of corroded copper patina by step scan and rapid scan photoacoustic Fourier transform infrared spectroscopy,” Rev. Sci. Instrum. 74(1), 331–333 (2003).
[Crossref]

Skin Res. Technol. (1)

I. Notingher and R. E. Imhof, “Mid-infrared in vivo depth-profiling of topical chemicals on skin,” Skin Res. Technol. 10(2), 113–121 (2004).
[Crossref] [PubMed]

Other (2)

Cobalt, Airport security. www.cobaltlight.com/security/ (Accessed February 2016)

C. Conti, M. Realini, C. Colombo, A. Botteon, and P. Matousek, “Contrasting confocal with defocusing microscale spatially offset Raman spectroscopy,” J. Raman Spectrosc.in press.

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Figures (7)

Fig. 1
Fig. 1

Schematic of the DMD-based SORS instrument. Abbreviations: OBJ, objective; IOM, inverted optical microscope; MSC, microscope side-port camera; DCM, dichroic mirror; LCF, laser clean filter; NDL, 20mW 532nm Nd:YAG diode laser; DMD, digital micro-mirror device; DRC, DMD inspection camera; NF, notch filter; SP, spectrometer; CCD, charge couple device detector. The red circles in the magnified images denote the position corresponding to the focused laser on the sample, and on the sample-conjugate plane of the DMD (equivalent to zero spatial offset). (i) shows a DMD pattern for a standard confocal Raman measurement (essentially a reflective pinhole), and (ii) shows one possible SORS configuration (semi-annulus).

Fig. 2
Fig. 2

(a) Semi-annulus pattern with radius of S displayed on DMD screen as collection zone and detection stripes imaged on the CCD camera using semi-circle collection geometry, 20s acquisition time. (b) Raman spectra of PS from the 16 collection lines shown in Fig. 2(a), each spectrum is the sum of 5 tracks. (c) The average spectrum from the measurement is shown in Fig. 2(b). The spectra are horizontally shifted to zero-offset position before averaging.

Fig. 3
Fig. 3

(a) Full-annular collection geometry for SORS spectra and Raman spectra captured on the spectrometer CCD; (b) Raman spectra corresponding to selected rows on the CCD, as indicated by 1, 2, 3, 4, 5. (c) Mean SORS spectra obtained by averaging the spectra from semi-annular geometry (top) and full-annular geometry (bottom). Overlapped spectra, such as row 2 in (b), were excluded. Laser power: 14 mW, acquisition time 5 seconds.

Fig. 4
Fig. 4

(a) Schematic description of the two-layer polymer samples used in the experiment for SORS demonstration. (b) The semi-annulus collection geometry displayed on DMD and used for collection of SORS spectra. (c) A set of spatial offset Raman spectra acquired from the two-layer structure consisting of d = 0.9 mm layer of PMMA sheet and 1.0 mm of PS sheet. The acquisition time was 20 s for each spectrum. Spatial offset is indicated next to each Raman spectrum. All the spectra are shown as raw without any post processing. (d) The ratio of Raman band intensity corresponding to the bottom layer (PS) and top layer (PMMA) as a function of the spatial offset. Red eye-guiding curves are exponential fittings to the data points.

Fig. 5
Fig. 5

(a) Two-layer sample structure of PMMA sheet and PS sheet for the multiple spatial offsets measurements. (b) The chevron pattern displayed on DMD. Each point in the arm represents a distinct spatial offset. (c) Stripes imaged on the CCD sensor using the chevron collection geometry. (d) A set of SORS spectra acquired from the two-layer polymer structure with PMMA thickness of 0.9 mm. The acquisition time was 20 s. Spatial offset is indicated next to the spectra. The spectra from pure PMMA and PS that obtained in separate measurements are also shown for comparison. (e) Ratio of Raman intensity of bottom layer (PS) to top layer (PMMA) as a function of spatial offset. Red curve is exponential fitting to the data points.

Fig. 6
Fig. 6

(a) Two-layer sample structure of PMMA sheet and PS sheet for micro-SORS measurements. (b) Raman spectra of a two-layer sample consisting of a 200 μm thick PMMA film on thick PS substrate, acquired using the DMD-based micro-SORS system. The acquisition time was 20s for each spectrum. Reference Raman spectra from pure PS and PMMA are also displayed in the top and bottom for comparison. (c) Raman intensity ratio of PS (1001 cm−1) to PMMA (809 cm−1) as a function of spatial offset, calculated from the spectra shown in Fig. 6(b). The data points are fitted with exponential decay function, shown as red curve in the plot.

Fig. 7
Fig. 7

(a) Schematic of a three-layer sample for micro-SORS experiment. (b) SORS spectra acquired using the semi-annulus collection geometry. The acquisition time for each spectrum was 20 s. Spatial offset is indicated next to the spectra. The spectra from pure PMMA, PS and HA (obtained in separate measurements) are also shown for comparison. (c) Raman intensity ratio of PS (1001 cm−1, black squares) and HA (961 cm−1, blue dots) to PMMA (809 cm−1) as a function of spatial offset, calculated from the spectra shown in Fig. 7(b). The data points are fitted with exponential decay function, shown as red curves in the plot.

Equations (3)

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Δx=S f 0 f m
Δλ dy dλ Δx f sp f o
ΔλΔx a f o

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