Applied Physics B

, Volume 116, Issue 4, pp 883–899 | Cite as

Absolute validation of a diode laser hygrometer via intercomparison with the German national primary water vapor standard

  • B. Buchholz
  • N. Böse
  • V. EbertEmail author


Direct tunable diode laser absorption spectroscopy (dTDLAS) is a powerful diagnostic technique for absolute and accurate gas analysis with highest chemical specificity. Due to its first principles approach, dTDLAS is often claimed to be “calibration-free”, but this and the absolute accuracy has not been rigorously validated with respect to a high-accuracy reference. This work describes the first rigorous, side-by-side comparison of a dTDLAS hygrometer—called SEALDH—with a highly accurate, internationally validated, primary reference humidity generator (PHG), which also serves as the German national H2O-standard. This PHG provides a humidified air stream with dew points between −30 °C and +60 °C with an uncertainty of 0.035 K (2σ) (equivalent relative H2O mixing ratio uncertainty: 0.4 %). Without any previous calibration, SEALDH was found to accurately reproduce the PHG reference values over the full range from 600 to 20,000 ppmv investigated in the 1-week lab study. Over this range, the SEALDH–PHG relative deviation was in average −1.45 %, the worst case being −2.5 % at 1,000 ppmv, the best −0.2 % at 600 ppmv. As SEALDH’s relative uncertainty was metrologically determined to be 4.3 % (k = 2), these deviations are for all concentration steps in full compliance with the PHG reference. Systematic contributions to the relative deviation could be correlated with line shape deviations between the measured line profile and the fitted Voigt line shape. Using this information, SEALDHs absolute accuracy can be improved further to down to an average relative deviation to the PHG of +0.21 %.


Line Strength Transfer Standard Tunable Diode Laser Absorption Spectroscopy Water Vapor Partial Pressure Humidity Generator 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. 1.
    M. Zöger, A. Afchine, N. Eicke, M.-T. Gerhards, E. Klein, D.S. McKenna, U. Mörschel, U. Schmidt, V. Tan, F. Tuitjer, T. Woyke, C. Schiller, Fast in situ stratospheric hygrometers: A new family of balloon-borne and airborne Lyman photofragment fluorescence hygrometers t VUV-A. J. Geophys. Res. 104(D1), 1807–1816 (1999)ADSCrossRefGoogle Scholar
  2. 2.
    C. Schulz, A. Dreizler, V. Ebert, J. Wolfrum, Combustion diagnostics, in Handbook of Experimental Fluid Mechanics, ed. by C. Tropea, A.L. Yarin, J.F. Foss (Springer, Berlin, 2007), pp. 1241–1316CrossRefGoogle Scholar
  3. 3.
    J. Wolfrum, T. Dreier, V. Ebert, C. Schulz, Laser-based combustion diagnostics, in Encyclopedia of Analytical Chemistry, 2nd edn., ed. by R.A. Meyers (Wiley, Chichester, 2011), p. 33. doi: 10.1002/9780470027318.a0715.pub2 Google Scholar
  4. 4.
    J.A. Silver, Frequency-modulation spectroscopy for trace species detection: theory and comparison among experimental methods: errata. Appl. Opt. 31(24), 707–717 (1992)ADSCrossRefGoogle Scholar
  5. 5.
    J. Reid, D. Labrie, Second-harmonic detection with tunable diode lasers—comparison of experiment and theory. Appl. Phys. B 26(3), 203–210 (1981)ADSCrossRefGoogle Scholar
  6. 6.
    V. Ebert, J. Wolfrum, Absorption spectroscopy, in Optical Measurements—Techniques and Applications, 2nd edn., ed. by F. Mayinger, O. Feldmann (Springer, München, 2001), pp. 227–265Google Scholar
  7. 7.
    M.R. Sargent, D.S. Sayres, J.B. Smith, M. Witinski, N.T. Allen, J.N. Demusz, M. Rivero, C. Tuozzolo, J.G. Anderson, A new direct absorption tunable diode laser spectrometer for high precision measurement of water vapor in the upper troposphere and lower stratosphere. Rev. Sci. Instrum. 84(7), 074102 (2013). doi: 10.1063/1.4815828 ADSCrossRefGoogle Scholar
  8. 8.
    A.K. Vance, A. Woolley, R. Cotton, K. Turnbull, S. Abel, C. Harlow, Final report on the WVSS-II sensors fitted to the FAAM BAe 146. Met Office, no. November, pp. 0–31, 2011Google Scholar
  9. 9.
    J. Silver, D. Hovde, Near-infrared diode laser airborne hygrometer. Rev. Sci. Instrum. 65(5), 1691–1694 (1994)ADSCrossRefGoogle Scholar
  10. 10.
    C. Webster, G. Flesch, K. Mansour, Mars laser hygrometer. Appl. Opt. 43(22), 4436–4445 (2004)ADSCrossRefGoogle Scholar
  11. 11.
    W. Gurlit, R. Zimmermann, C. Giesemann, T. Fernholz, V. Ebert, J. Wolfrum, U.U. Platt, J.P. Burrows, Lightweight diode laser spectrometer ‘CHILD’ for balloon-borne measurements of water vapor and methane. Appl. Opt. 44(1), 91–102 (2005)ADSCrossRefGoogle Scholar
  12. 12.
    G.S. Diskin, J.R. Podolske, G.W. Sachse, T.A. Slate, Open-path airborne tunable diode laser hygrometer. Proc. SPIE 4817, 196–204 (2002)ADSCrossRefGoogle Scholar
  13. 13.
    M. Zondlo, M.E. Paige, S.M. Massick, J. Silver, Vertical cavity laser hygrometer for the National Science Foundation Gulfstream-V aircraft. J. Geophys. Res. 115(D20) (2010). doi: 10.1029/2010JD014445
  14. 14.
    J. Podolske, G. Sachse, G. Diskin, Calibration and data retrieval algorithms for the NASA Langley/Ames Diode Laser Hygrometer for the NASA transport and chemical evolution over the Pacific (TRACE-P) mission. J. Geophys. Res. 108(D20), 8792 (2003). doi: 10.1029/2002JD003156 CrossRefGoogle Scholar
  15. 15.
    B. Lins, R. Engelbrecht, B. Schmauss, Software-switching between direct absorption and wavelength modulation spectroscopy for the investigation of ADC resolution requirements. Appl. Phys. B 106(4), 999–1008 (2012). doi: 10.1007/s00340-011-4827-2 ADSCrossRefGoogle Scholar
  16. 16.
    V. Ebert, T. Fernholz, H. Pitz, In-situ monitoring of water vapour and gas temperature in a coal fired power-plant using near-infrared diode lasers, in Laser Applications to Chemical and Environmental Analysis, pp. 4–6 (2000)Google Scholar
  17. 17.
    S. Hunsmann, K. Wunderle, S. Wagner, Absolute, high resolution water transpiration rate measurements on single plant leaves via tunable diode laser absorption spectroscopy (TDLAS) at 1.37 μm. Appl. Phys. B 92(3), 393–401 (2008). doi: 10.1007/s00340-008-3095-2 ADSCrossRefGoogle Scholar
  18. 18.
    B.A. Paldus, A. Kachanov, An historical overview of cavity-enhanced methods. Can. J. Phys. 83(10), 975–999 (2005)ADSCrossRefGoogle Scholar
  19. 19.
    D. Atkinson, Cavity ring-down spectroscopy: techniques and applications. J. Am. Chem. Soc. 132(13), 4972 (2010)CrossRefGoogle Scholar
  20. 20.
    A. Farooq, J. Jeffries, R. Hanson, In situ combustion measurements of H2O and temperature near 2.5 μm using tunable diode laser absorption. Meas. Sci. Technol. 19(7), 075604 (2008). doi: 10.1088/0957-0233/19/7/075604 ADSCrossRefGoogle Scholar
  21. 21.
    R. Mihalcea, D. Baer, R. Hanson, Diode laser sensor for measurements of CO, CO2, and CH4 in combustion flows. Appl. Opt. 36(33), 8745–8752 (1997)ADSCrossRefGoogle Scholar
  22. 22.
    T. Peter, C. Marcolli, P. Spichtinger, T. Corti, When dry air is too humid. Science 314, December (2006)Google Scholar
  23. 23.
    A. Mangold et al., Intercomparison of water vapour detectors under field and defined conditions, in EGS-AGU-EUG Joint Assembly, vol. 1 (2003)Google Scholar
  24. 24.
    A. Hoff, WVSS-II assessment at the DWD Deutscher Wetterdienst/German Meteorological Service Climate Chamber of the Meteorological Observatory Lindenberg, Deutscher Wetterdienst, September 2009Google Scholar
  25. 25.
    D. Fahey, R. Gao, Summary of the AquaVIT water vapor intercomparison: static experiments., 2009
  26. 26.
    O. Möhler, O. Stetzer, S. Schaefers, C. Linke, M. Schnaiter, R. Tiede, H. Saathoff, M. Krämer, A. Mangold, P. Budz, P. Zink, J. Schreiner, K. Mauersberger, W. Haag, B. Kärcher, U. Schurath, Experimental investigation of homogeneous freezing of sulphuric acid particles in the aerosol chamber AIDA. Atmos. Chem. Phys. 3(1), 211–223 (2003). doi: 10.5194/acp-3-211-2003 ADSCrossRefGoogle Scholar
  27. 27.
    M. Heinonen, A comparison of humidity standards at seven European national standards laboratories. Metrologia 39, 303–308 (2002). doi: 10.1088/0026-1394/39/3/7
  28. 28.
    M. Heinonen, M. Anagnostou, S. Bell, M. Stevens, R. Benyon, R. A. Bergerud, J. Bojkovski, R. Bosma, J. Nielsen, N. Böse, P. Cromwell, A. Kartal Dogan, S. Aytekin, A. Uytun, V. Fernicola, K. Flakiewicz, B. Blanquart, D. Hudoklin, P. Jacobson, A. Kentved, I. Lóio, G. Mamontov, A. Masarykova, H. Mitter, R. Mnguni, J. Otych, A. Steiner, N. Szilágyi Zsófia, D. Zvizdic, Investigation of the equivalence of national dew-point temperature realizations in the −50 °C to +20 °C Range. Int. J. Thermophys. 33(8–9), 1422–1437 (2011). doi: 10.1007/s10765-011-0950-x Google Scholar
  29. 29.
  30. 30.
    R. Busen, A.L. Buck, A high-performance hygrometer for aircraft use: description, installation, and flight data. J. Atmos. Ocean. Technol. 12, 73 (1995)ADSCrossRefGoogle Scholar
  31. 31.
    J.A. Nwaboh, O. Werhahn, P. Ortwein, D. Schiel, V. Ebert, Laser-spectrometric gas analysis: CO2—TDLAS at 2 μm. Meas. Sci. Technol. 24, 015202 (2013). doi: 10.1088/0957-0233/24/1/015202 ADSCrossRefGoogle Scholar
  32. 32.
    K. Jousten, G. Padilla-Víquez, T. Bock, Investigation of tunable diode laser absorption spectroscopy for its application as primary standard for partial pressure measurements. J. Phys: Conf. Ser. 100(9), 092005 (2008). doi: 10.1088/1742-6596/100/9/092005 ADSGoogle Scholar
  33. 33.
    H.I. Schiff, G.I. Mackay, J. Bechara, The use of tunable diode laser absorption spectroscopy for atmospheric measurements. Res. Chem. Intermed. 20(3), 525–556 (1994). doi: 10.1163/156856794X00441 CrossRefGoogle Scholar
  34. 34.
    R.D. May, Open-path, near-infrared tunable diode laser spectrometer for atmospheric measurements of H2O. J. Geophys. Res. 103(D15), 19161–19172 (1998)ADSCrossRefGoogle Scholar
  35. 35.
    D. Hovde, J. Hodges, G. Scace, J. Silver, Wavelength-modulation laser hygrometer for ultrasensitive detection of water vapor in semiconductor gases. Appl. Opt. 40(6), 829–839 (2001)ADSCrossRefGoogle Scholar
  36. 36.
    C. Lauer, D. Weber, S. Wagner, V. Ebert, Calibration free measurement of atmospheric methane background via tunable diode laser absorption spectroscopy at 1.6 μm. Laser Applications to Chemical, Security and Environmental Analysis, OSA Technical Digest (CD) (Optical Society of America), vol. LMA2, 2008Google Scholar
  37. 37.
    O. Witzel, A. Klein, C. Meffert, S. Wagner, C. Meffert, C. Schulz, V. Ebert, VCSEL-based, high-speed, in situ TDLAS for in-cylinder water vapor measurements in IC engines. Opt. Express 21(17), 19951–19965 (2013)CrossRefGoogle Scholar
  38. 38.
    K. Wunderle, S. Wagner, I. Pasti, Distributed feedback diode laser spectrometer at 2.7 μm for sensitive, spatially resolved H2O vapor detection. Appl. Opt. 48(4), B172–B182 (2009)ADSCrossRefGoogle Scholar
  39. 39.
    A.R. Awtry, B.T. Fisher, R.A. Moffatt, V. Ebert, J.W. Fleming, Simultaneous diode laser based in situ quantification of oxygen, carbon monoxide, water vapor, and liquid water in a dense water mist environment. Proc. Combust. Inst. 31, 799–806 (2007). doi: 10.1016/j.proci.2006.07.046 CrossRefGoogle Scholar
  40. 40.
    V. Ebert, T. Fernholz, C. Giesemann, H. Pitz, H. Teichert, J. Wolfrum, H. Jaritz, Simultaneous diode-laser-based in situ detection of multiple species and temperature in a gas-fired power plant. Proc. Combust. Inst. 28, 423–430 (2000)CrossRefGoogle Scholar
  41. 41.
    V. Ebert, J. Fitzer, I. Gerstenberg, K.-U. Pleban, H. Pitz, J. Wolfrum, M. Jochem, J. Martin, Simultaneous laser-based in situ detection of oxygen and water in a waste incinerator for active combustion control purposes. Proc. Combust. Inst. 27, 1301–1308 (1998). doi: 10.1016/S0082-0784(98)80534-1 CrossRefGoogle Scholar
  42. 42.
    H.E. Schlosser, T. Fernholz, H. Teichert, V. Ebert, In situ detection of potassium atoms in high-temperature coal-combustion systems using near-infrared-diode lasers. Spectrochim. Acta Part A Mol. Biomol. Spectrosc. 58(11), 2347–2359 (2002)ADSCrossRefGoogle Scholar
  43. 43.
    L.S. Rothman, I.E. Gordon, A. Barbe, D.C. Benner, P.F. Bernath, M. Birk, V. Boudon, L.R. Brown, A. Campargue, J.-P. Champion, The HITRAN 2008 molecular spectroscopic database. J. Quantum Spectrosc. Radiat. Transf. 110(9–10), 533–572 (2009). doi: 10.1016/j.jqsrt.2009.02.013 ADSCrossRefGoogle Scholar
  44. 44.
    S. Hunsmann, S. Wagner, H. Saathoff, O. Möhler, U. Schurath, V. Ebert, Messung der Temperaturabhängigkeit der Linienstärken und Druckverbreiterungskoeffizienten von H2O-Absorptionslinien im 1.4 μm band. VDI Berichte (1959) VDI Verlag, Düsseldorf, pp. 149–164, 2006Google Scholar
  45. 45.
    R.J. Muecke, B. Scheumann, F. Slemr, P.W. Werle, Calibration procedures for tunable diode laser spectrometers, in SPIE’s International Symposium on Optical Sensing for Environmental Monitoring, pp. 87–98, 1994Google Scholar
  46. 46.
    K. Wunderle, T. Fernholz, V. Ebert, Selection of optimal absorption lines for tunable laser absorption spectrometers. VDI Berichte 1959, 137–148 (2006)Google Scholar
  47. 47.
    S. Wagner, M. Klein, T. Kathrotia, U. Riedel, Absolute, spatially resolved, in situ CO profiles in atmospheric laminar counter-flow diffusion flames using 2.3 μm TDLAS. Appl. Phys. B 109(3), 533–540 (2012). doi: 10.1007/s00340-012-5242-z ADSCrossRefGoogle Scholar
  48. 48.
    B. Buchholz, B. Kühnreich, H.G.J. Smit, V. Ebert, Validation of an extractive, airborne, compact TDL spectrometer for atmospheric humidity sensing by blind intercomparison. Appl. Phys. B 110(2), 249–262 (2013). doi: 10.1007/s00340-012-5143-1 ADSCrossRefGoogle Scholar
  49. 49.
    B. Buchholz, N. Böse, S. Wagner, V. Ebert, Entwicklung eines rückführbaren, selbstkalibrierenden, absoluten TDLAS-Hygrometers in kompakter 19 “Bauweise”, in AMA-Science, 16. GMA/ITG-Fachtagung Sensoren und Messsysteme 2012, pp. 315–323, 2012. doi: 10.5162/sensoren2012/3.2.3
  50. 50.
    V. Ebert, H. Teichert, C. Giesemann, H. Saathoff, U. Schurath, Fasergekoppeltes In-situ-Laserspektrometer für den selektiven Nachweis von Wasserdampfspuren bis in den ppb-Bereich. tm—Tech. Mess. 72(1), 23–30 (2004). doi: 10.1524/teme. Google Scholar
  51. 51.
    A. Seidel, S. Wagner, V. Ebert, TDLAS-based open-path laser hygrometer using simple reflective foils as scattering targets. Appl. Phys. B 109(3), 497–504 (2012). doi: 10.1007/s00340-012-5228-x ADSCrossRefGoogle Scholar
  52. 52.
    O. Witzel, A. Klein, S. Wagner, C. Meffert, C. Schulz, V. Ebert, High-speed tunable diode laser absorption spectroscopy for sampling-free in-cylinder water vapor concentration measurements in an optical IC engine. Appl. Phys. B 109(3), 521–532 (2012). doi: 10.1007/s00340-012-5225-0 ADSCrossRefGoogle Scholar
  53. 53.
    V. Ebert, In situ absorption spectrometers using near-IR diode lasers and rugged multi-path-optics for environmental field measurements, in Laser Applications to Chemical, Security and Environmental Analysis, Technical Digest (Optical Society of America), vol. WB1, 2006Google Scholar
  54. 54.
    K. Wunderle, B. Al-Zaitone, I. Pašti, S. Wagner, S. Hunsmann, C. Tropea, V. Ebert, TDLAS-Spektrometer zur räumlich aufgelösten absoluten Wasserdampfbestimmung um akustisch levitierte Einzeltröpfchen. VDI-Berichte 2047, 103–112 (2008)Google Scholar
  55. 55.
    A. Marenco, V. Thouret, P. Nédélec, Measurement of ozone and water vapor by Airbus in-service aircraft: The MOZAIC airborne program. An overview. J. Geophys. Res. 103(D19), 25631–25725 (1998)ADSCrossRefGoogle Scholar
  56. 56.
    High Altitude and LOng range research aircraft., 2012
  57. 57.
    R. Petersen, L. Cronce, W. Feltz, E. Olson, D. Helms, WVSS-II moisture observations: a tool for validating and monitoring satellite moisture data. EUMETSAT Meteorological Satellite Conference, vol. 22, pp. 67–77, (2010)Google Scholar
  58. 58.
    P. Mackrodt, A new attempt on a coulometric trace humidity generator. Int. J. Thermophys. 33(8–9), 1520–1535 (2012). doi: 10.1007/s10765-012-1348-0 ADSCrossRefGoogle Scholar
  59. 59.
    D. Sonntag, Important new values of the physical constants of 1968, vapour pressure formulations based on the ITS-90, and psychrometer formulae. Z Meteorol 40, 340–344 (1990)Google Scholar
  60. 60.
    D.M. Murphy, T. Koop, Review of the vapour pressures of ice and supercooled water for atmospheric applications. Q. J. R. Meteorolog. Soc. 131(608), 1539–1565 (2005). doi: 10.1256/qj.04.94 CrossRefGoogle Scholar
  61. 61.
    J. Marti, K. Mauersberger, A survey and new measurements of ice vapor pressure at temperatures between 170 and 250 K. Geophys. Res. Lett. 20(5), 363–366 (1993)ADSCrossRefGoogle Scholar
  62. 62.
    A. Wexler, Vapor pressure formulation for water in range 0 to 100 C. A revision. J. Res. Natl. Bur. Stand. Sect. A: Phys. Chem. 80A(5–6), 775 (1976). doi: 10.6028/jres.080A.071 CrossRefGoogle Scholar
  63. 63.
    A. Wexler, Vapor pressure formulation for ice. J. Res. Natl. Bur. Stand. Sect. A: Phys. Chem. 81(1), 5–19 (1977)CrossRefGoogle Scholar
  64. 64.
    R.W. Hyland, A. Wexter, Formulations for the thermodynamic properties of the saturated phases of H2O from 173.15 K to 473.15 K. ASHRAE Trans. 89(2A), 500–519 (1983)Google Scholar
  65. 65.
    L. Greenspan, Functional equations for the enhancement factors for CO2-free moist air. J. Res. NBS: A Phys. Chem. 80A(1), 41–44 (1976)CrossRefGoogle Scholar
  66. 66.
    Evaluation of measurement data—an introduction to the ‘Guide to the expression of uncertainty in measurement’ and related documents. Joint Committee for Guides in Metrology, JCGM no. 104, 2009Google Scholar
  67. 67.
    BIPM, Evaluation of measurement data—guide to the expression of uncertainty in measurement. Joint Committee for Guides in Metrology, JCGM no. 100, 2008.
  68. 68.
    D.W. Allan, Statistics of atomic frequency standards. Proc. IEEE 54(2), 221–230 (1966). doi: 10.1109/PROC.1966.4634 CrossRefGoogle Scholar
  69. 69.
    P. Werle, R. Mücke, F. Slemr, The limits of signal averaging in atmospheric trace-gas monitoring by tunable diode-laser absorption spectroscopy (TDLAS). Appl. Phys. B 57(2), 131–139 (1993)ADSCrossRefGoogle Scholar
  70. 70.
    P. Maddaloni, P. Malara, P. De Natale, Simulation of Dicke-narrowed molecular spectra recorded by off-axis high-finesse optical cavities. Mol. Phys. 06, 749–755 (2010)ADSCrossRefGoogle Scholar
  71. 71.
    A.W. Rollins, T.D. Thornberry, R.-S. Gao, B.D. Hall, D.W. Fahey, Catalytic oxidation of H2 on platinum: a robust method for generating low mixing ratio H2O standards. Atmos. Meas. Tech. 4(10), 2059–2064 (2011). doi: 10.5194/amt-4-2059-2011 CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Physikalisch-Technische Bundesanstalt (PTB)BrunswickGermany
  2. 2.Center of Smart Interfaces (CSI)Technische Universität DarmstadtDarmstadtGermany

Personalised recommendations