Abstract

We report on a dual-diode laser spectroscopic system for simultaneous detection of two gases. The technique is demonstrated by performing gas measurements on absorbing samples such as an air distance, and on absorbing and scattering porous samples such as human tissue. In the latter it is possible to derive the concentration of one gas by normalizing to a second gas of known concentration. This is possible if the scattering and absorption of the bulk material is equal or similar for the two wavelengths used, resulting in a common effective pathlength. Two pigtailed diode lasers are operated in a wavelength modulation scheme to detect molecular oxygen 760nm and water vapor 935nm within the tissue optical window (600nm to 1.3μm). Different modulation frequencies are used to distinguish between the two wavelengths. No crosstalk can be observed between the gas contents measured in the two gas channels. The system is made compact by using a computer board and performing software-based lock-in detection. The noise floor obtained corresponds to an absorption fraction of approximately 6×10-5 for both oxygen and water vapor, yielding a minimum detection limit of 2mm for both gases in ambient air. The power of the technique is illustrated by the preliminary results of a clinical trial, nonintrusively investigating gas in human sinuses.

© 2008 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |

  1. J. Faist, F. Capasso, D. Sivco, C. Sirtori, A. Hutchinson, and A. Cho, “Quantum cascade laser,” Science 264, 553-556 (1994).
    [CrossRef] [PubMed]
  2. G. Wysocki, M. McCurdu, S. So, D. Weidmann, C. Roller, R. Curl, and F. Tittel, “Pulsed quantum-cascade laser-based sensor for trace-gas detection of carbonyl sulfide,” Appl. Opt. 43, 6040-6046 (2004).
    [CrossRef] [PubMed]
  3. M. Silva, D. Sonnenfroh, D. Rosen, M. Allen, and A. O'Keefe, “Integrated cavity output spectroscopy measurements of nitric oxide levels in breath with a pulsed room-temperature quantum cascade laser,” Appl. Phys. B 81, 705-710 (2005).
    [CrossRef]
  4. J. Parrish, “New concepts in therapeutic photomedicine: photochemistry, optical targeting and the therapeutic window,” J. Investigative Dermatol. 77, 45-50 (1981).
    [CrossRef]
  5. J. Boulnois, “Photophysical processes in recent medical laser developments: a review,” Lasers Med. Sci. 1, 47-66 (1986).
    [CrossRef]
  6. G. Somesfalean, Z. Zhang, M. Sjöholm, and S. Svanberg, “All-diode-laser ultraviolet absorption spectroscopy for sulfur dioxide detection,” Appl. Phys. B 80, 1021-1025 (2005).
    [CrossRef]
  7. U. Gustafsson, J. Sandsten, and S. Svanberg, “Simultaneous detection of methane, oxygen and water vapour utilizing near-infrared diode lasers in conjunction with difference frequency generation,” Appl. Phys. B 71, 853-857 (2000).
  8. J. Reid and D. Labrie, “Second-harmonic detection with tunable diode lasers--comparison of experiment and theory,” Appl. Phys. B 26, 203-210 (1981).
    [CrossRef]
  9. 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, 113107 (2007).
    [CrossRef] [PubMed]
  10. L. Persson, F. Andersson, M. Andersson, and S. Svanberg, “Approach to optical interference fringes reduction in diode laser absorption spectroscopy,” Appl. Phys. B 87, 523-530 (2007).
    [CrossRef]
  11. L. Persson, M. Andersson, T. Svensson, M. Cassel-Engquist, K. Svanberg, and S. Svanberg, “Non-intrusive optical study of gas and its exchange in human maxillary sinuses,” Proc. SPIE 6628, 662804-1-7 (2007).
  12. L. Persson, M. Andersson, M. Cassel-Engquist, K. Svanberg, and S. Svanberg, “Gas monitoring in human sinuses using tunable diode laser spectroscopy,” J Biomed. Opt. 12, 054001(2007).
    [CrossRef] [PubMed]

2007 (4)

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, 113107 (2007).
[CrossRef] [PubMed]

L. Persson, F. Andersson, M. Andersson, and S. Svanberg, “Approach to optical interference fringes reduction in diode laser absorption spectroscopy,” Appl. Phys. B 87, 523-530 (2007).
[CrossRef]

L. Persson, M. Andersson, T. Svensson, M. Cassel-Engquist, K. Svanberg, and S. Svanberg, “Non-intrusive optical study of gas and its exchange in human maxillary sinuses,” Proc. SPIE 6628, 662804-1-7 (2007).

L. Persson, M. Andersson, M. Cassel-Engquist, K. Svanberg, and S. Svanberg, “Gas monitoring in human sinuses using tunable diode laser spectroscopy,” J Biomed. Opt. 12, 054001(2007).
[CrossRef] [PubMed]

2005 (2)

M. Silva, D. Sonnenfroh, D. Rosen, M. Allen, and A. O'Keefe, “Integrated cavity output spectroscopy measurements of nitric oxide levels in breath with a pulsed room-temperature quantum cascade laser,” Appl. Phys. B 81, 705-710 (2005).
[CrossRef]

G. Somesfalean, Z. Zhang, M. Sjöholm, and S. Svanberg, “All-diode-laser ultraviolet absorption spectroscopy for sulfur dioxide detection,” Appl. Phys. B 80, 1021-1025 (2005).
[CrossRef]

2004 (1)

2000 (1)

U. Gustafsson, J. Sandsten, and S. Svanberg, “Simultaneous detection of methane, oxygen and water vapour utilizing near-infrared diode lasers in conjunction with difference frequency generation,” Appl. Phys. B 71, 853-857 (2000).

1994 (1)

J. Faist, F. Capasso, D. Sivco, C. Sirtori, A. Hutchinson, and A. Cho, “Quantum cascade laser,” Science 264, 553-556 (1994).
[CrossRef] [PubMed]

1986 (1)

J. Boulnois, “Photophysical processes in recent medical laser developments: a review,” Lasers Med. Sci. 1, 47-66 (1986).
[CrossRef]

1981 (2)

J. Reid and D. Labrie, “Second-harmonic detection with tunable diode lasers--comparison of experiment and theory,” Appl. Phys. B 26, 203-210 (1981).
[CrossRef]

J. Parrish, “New concepts in therapeutic photomedicine: photochemistry, optical targeting and the therapeutic window,” J. Investigative Dermatol. 77, 45-50 (1981).
[CrossRef]

Appl. Opt. (1)

Appl. Phys. B (5)

M. Silva, D. Sonnenfroh, D. Rosen, M. Allen, and A. O'Keefe, “Integrated cavity output spectroscopy measurements of nitric oxide levels in breath with a pulsed room-temperature quantum cascade laser,” Appl. Phys. B 81, 705-710 (2005).
[CrossRef]

G. Somesfalean, Z. Zhang, M. Sjöholm, and S. Svanberg, “All-diode-laser ultraviolet absorption spectroscopy for sulfur dioxide detection,” Appl. Phys. B 80, 1021-1025 (2005).
[CrossRef]

U. Gustafsson, J. Sandsten, and S. Svanberg, “Simultaneous detection of methane, oxygen and water vapour utilizing near-infrared diode lasers in conjunction with difference frequency generation,” Appl. Phys. B 71, 853-857 (2000).

J. Reid and D. Labrie, “Second-harmonic detection with tunable diode lasers--comparison of experiment and theory,” Appl. Phys. B 26, 203-210 (1981).
[CrossRef]

L. Persson, F. Andersson, M. Andersson, and S. Svanberg, “Approach to optical interference fringes reduction in diode laser absorption spectroscopy,” Appl. Phys. B 87, 523-530 (2007).
[CrossRef]

J Biomed. Opt. (1)

L. Persson, M. Andersson, M. Cassel-Engquist, K. Svanberg, and S. Svanberg, “Gas monitoring in human sinuses using tunable diode laser spectroscopy,” J Biomed. Opt. 12, 054001(2007).
[CrossRef] [PubMed]

J. Investigative Dermatol. (1)

J. Parrish, “New concepts in therapeutic photomedicine: photochemistry, optical targeting and the therapeutic window,” J. Investigative Dermatol. 77, 45-50 (1981).
[CrossRef]

Lasers Med. Sci. (1)

J. Boulnois, “Photophysical processes in recent medical laser developments: a review,” Lasers Med. Sci. 1, 47-66 (1986).
[CrossRef]

Proc. SPIE (1)

L. Persson, M. Andersson, T. Svensson, M. Cassel-Engquist, K. Svanberg, and S. Svanberg, “Non-intrusive optical study of gas and its exchange in human maxillary sinuses,” Proc. SPIE 6628, 662804-1-7 (2007).

Rev. Sci. Instrum. (1)

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, 113107 (2007).
[CrossRef] [PubMed]

Science (1)

J. Faist, F. Capasso, D. Sivco, C. Sirtori, A. Hutchinson, and A. Cho, “Quantum cascade laser,” Science 264, 553-556 (1994).
[CrossRef] [PubMed]

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (7)

Fig. 1
Fig. 1

Schematic of the experimental arrangement for simultaneous detection of molecular oxygen ( 760 nm ) and water vapor ( 935 nm ) using tunable diode laser gas absorption spectroscopy. The sample can either be an absorbing sample such as an air distance or an absorbing and scattering sample such as human tissue.

Fig. 2
Fig. 2

Typical recorded oxygen and water vapor signals after background subtraction for measurements over an air distance of 20 mm . Insets can be seen in the 1 f signal plots enhancing the intensity region of interest for signals due to gas imprint. The balanced-detection 2 f signal is shown (black) together with a fitted experimental ideal line shape (gray line). The relative frequency range for both gases corresponds to 35 GHz .

Fig. 3
Fig. 3

Recorded laser relative intensity noise (RIN) expressed in relative dB, to investigate possible crosstalk between the two modulation frequencies used to detect two gases simultaneously. The fiber and the sample detector have been separated with an air distance of 25 mm . To the right the frequency regions of interest are plotted. (a) Both lasers on. (b) Only laser for oxygen detection on. (c) Only laser for water vapor detection on. (d) No laser on.

Fig. 4
Fig. 4

Investigation of possible crosstalk between the two modulation frequencies used to detect two gases simultaneously. The balanced-detection signals are recorded from measurements over an air distance of 25 mm . The balanced-detection 2 f signals are shown (black line) together with a fitted experimental ideal line shape (gray line). The relative frequency range for both gases corresponds to 35 GHz .

Fig. 5
Fig. 5

(a) CT image of human frontal sinuses of a patient participating in the clinical trial; transversal section. (b) Corresponding recorded balanced-detection signals (black line) from the left frontal sinus of the patient with CT image shown in Fig. 5a, together with fitted ideal signal (gray line). The oxygen signal corresponds to L eq = 22 mm and the water vapor signal to L eq = 123 mm . (c) Recorded balanced-detection control signal through the cheek. The relative frequency range for both gases corresponds to 35 GHz .

Fig. 6
Fig. 6

(a) CT image of human maxillary sinuses of a patient participating in the clinical trial; transversal section. (b) Corresponding recorded balanced-detection signals (black line) from the right maxillary sinus of the patient with CT image shown in Fig. 6a, together with fitted ideal signal (gray line). The oxygen signal corresponds to L eq = 30 mm and the water vapor signal to L eq = 185 mm . (c) Recorded balanced-detection control signal through the cheek. The relative frequency range for both gases corresponds to 35 GHz .

Fig. 7
Fig. 7

Ventilation study between nasal cavity and maxillary sinus. (a)  L eq for oxygen (solid dots) measured as a function of time with N 2 flushing together with a curve drawn for guidance of the eye (dashed line). (b)  L eq for water vapor (solid dots) measured as a function of time with N 2 flushing. (c) Ratio between measured oxygen signal and water vapor signal (solid dots) as a function of time with N 2 flushing together with a curve drawn for guidance of the eye (dashed line). (d) Recorded balanced-detection 2 f signal (black line) together with a fitted experimental ideal line shape (gray line). The numbers correspond to those indicated in (a) and (b). The relative frequency range for both gases corresponds to 35 GHz .

Tables (1)

Tables Icon

Table 1 Average L eq from Ten Recordings over an Air Distance of ~ 25 mm to Investigate Possible Crosstalk between the Two Modulation Frequencies Used to Study Two Gases Simultaneously a

Metrics