Mid-infrared (MIR) supercontinuum (SC) lasers are an attractive new option in the field of IR spectroscopy, especially for standoff detection. Supercontinuum radiation unites high brightness, high spatial coherence, and broadband spectral coverage, thereby surpassing thermal IR sources and challenging quantum cascade lasers. The employed SC source operates in the spectral region of 1.2–4.6 µm, filling the spectral gap where quantum cascade lasers lack broader availability. In this work, the SC radiation was recorded by compact Fabry–Pérot filter spectrometers ideally suited for sensitive standoff detection with real-time capability. The noise performance of the setup and measurements of different substances at standoff distances are presented, e.g., of different paints on a metal surface and an explosive precursor. Furthermore, the real-time capability of the setup is demonstrated by monitoring the evaporation of liquid 2-propanol.
AlfanoR.R.The Supercontinuum Laser Source: The Ultimate White Light, New York: Springer Science and Business Media, 2016.
2.
HeiseB.SchausbergerS.E.HäuserS.PlankB.et al.“Full-Field Optical Coherence Microscopy with a Sub-Nanosecond Supercontinuum Light Source for Material Research”. Opt. Fiber Technol. 2012. 18(5): 403–410.
3.
HumbertG.WadsworthW.Leon-SavalS.KnightJ.et al.“Supercontinuum Generation System for Optical Coherence Tomography Based on tapered Photonic Crystal Fibre”. Opt. Express. 2006. 14(4): 1596.
4.
PetersenC.R.MøllerU.KubatI.ZhouB.et al.“Mid-Infrared Supercontinuum Covering the 1.4–13.3 µm Molecular Fingerprint Region Using Ultra-High NA Chalcogenide Step-Index Fibre”. Nat. Photonics. 2014. 8(11): 830–834.
5.
ZhaoZ.WuB.WangX.PanZ.et al.“Mid-infrared Supercontinuum Covering 2.0-16 µm in a Low-Loss Telluride Single-Mode Fiber”. Laser Photon. Rev. 2017. 11(2): 1770023.
6.
KedenburgS.StrutynskiC.KiblerB.FroidevauxP.et al.“High Repetition Rate Mid-Infrared Supercontinuum Generation from 13 to 53 µm in Robust Step-Index Tellurite Fibers”. J. Opt. Soc. Am. B. 2017. 34(3): 601–607.
7.
SalemR.JiangZ.LiuD.PafchekR.et al.“Mid-Infrared Supercontinuum Generation Spanning 18 Octaves Using Step-Index Indium Fluoride Fiber Pumped by a Femtosecond Fiber Laser Near 2 µm”. Opt. Express. 2015. 23(24): 30592–30602.
8.
LiuK.LiuJ.ShiH.TanF.et al.“High Power Mid-Infrared Supercontinuum Generation in a Single-Mode ZBLAN Fiber with up to 218 W Average Output Power”. Opt. Express. 2014. 22(20): 24384.
9.
J. Kilgus, P. Müller, P.M. Moselund, M. Brandstetter. “Application of Supercontinuum Radiation for Mid-Infrared Spectroscopy”. In: F. Berghmans, A.G. Mignani, editors. Proc. SPIE 9899, Optical Sensing and Detection IV, 98990K (29 April 2016).
10.
SwiderskiJ.“High-Power Mid-Infrared Supercontinuum Sources: Current Status and Future Perspectives”. Prog. Quantum Electron. 2014. 38(5): 189–235.
11.
TittelF.K.RichterD.FriedA.“Mid-Infrared Laser Applications in Spectroscopy”. In: SorokinaI.T.VodpyanovK.L. (eds). Solid-State Mid-Infrared Laser Sources. Topics in Applied Physics, Berlin; Heidelberg: Springer-Verlag, 2003, pp. 458–529.
12.
BrownD.M.BrownA.M.EdwardsP.S.LiuZ.et al.“Measurement of Atmospheric Oxygen Using Long-Path Supercontinuum Absorption Spectroscopy”. J. Appl. Remote Sens. International Society for Optics and Photonics. 2014. 8(1): 83557.
13.
G.G.C. Amiot, P. Ryczkowski, A. Aalto, J. Toivonen. “Multi-Component Gas Detection in the Mid-IR”. SPIE Newsroom, 2016. DOI: 10.1117/2.1201510.006199.
14.
KumarM.IslamM.N.TerryF.L.FreemanM.J.et al.“Stand-Off Detection of Solid Targets with Diffuse Reflection Spectroscopy Using a High-Power Mid-Infrared Supercontinuum Source”. Appl. Opt. 2012. 51(15): 2794.
15.
SkvortsovL.A.“Laser Methods for detecting Explosive Residues on Surfaces of Distant Objects”. Quantum Electron. 2012. 42(1): 1–11.
16.
WallinS.PetterssonA.ÖstmarkH.HobroA.“Laser-Based Standoff Detection of Explosives: A Critical Review”. Anal. Bioanal. 2009. 395(2): 259–274.
17.
ZachhuberB.GasserC.RamerG.ChrysostomE.t.H.et al.“Depth Profiling for the Identification of Unknown Substances and Concealed Content at Remote Distances Using Time-Resolved Stand-Off Raman Spectroscopy”. Appl. Spectrosc. 2012. 66(8): 875–881.
18.
MiziolekA.W.MunsonC.A.De LuciaF.C.GottfriedJ.L.“Standoff Detection of Chemical and Biological Threats Using Laser-Induced Breakdown Spectroscopy”. Appl. Spectrosc. 2008. 62(4): 353–363.
19.
BauerC.GeiserP.BurgmeierJ.HollG.et al.“Pulsed Laser Surface Fragmentation and Mid-Infrared Laser Spectroscopy for Remote Detection of Explosives”. Appl. Phys. B. 2006. 85(2–3): 251–256.
20.
N.A. MacLeod, D. Weidmann. “Active Coherent Laser Spectrometer for Remote Detection and Identification of Chemicals”. Proceedings Volume 8546, Optics and Photonics for Counterterrorism, Crime Fighting, and Defence VIII; 85460H (2012); doi: 10.1117/12.974521.
21.
BererT.BrandstetterM.HochreinerA.LangerG.et al.“Remote Mid-Infrared Photoacoustic Spectroscopy with a Quantum Cascade Laser”. Opt. Lett. 2015. 40(15): 3476–3479.
22.
Van NesteC.W.SenesacL.R.ThundatT.“Standoff Spectroscopy of Surface Adsorbed Chemicals”. Anal. Chem. 2009. 81(5): 1952–1956.
23.
SharmaR.C.KumarD.BhardwajN.GuptaS.et al.“Portable Detection System for Standoff Sensing of Explosives and Hazardous Materials”. Opt. Commun. 2013. 309: 44–49.
24.
LiJ.S.YuB.FischerH.ChenW.et al.“Quantum Cascade Laser Based Photoacoustic Detection of Explosives”. Rev. Sci. Instrum. 2015. 86(3): 31501.
25.
SuterJ.D.BernackiB.PhillipsM.C.“Spectral and Angular Dependence of Mid-Infrared Diffuse Scattering from Explosives Residues for Standoff Detection Using External Cavity Quantum Cascade Lasers”. Appl. Phys. B. 2012. 108(4): 965–974.
26.
IwataT.“Fabry–Perot Interferometers for Mid-Infrared Spectroscopy”. In: GriffithsP.R. (ed). Handbook of Vibrational Spectroscopy, Chichester, UK: John Wiley and Sons, Ltd, 2006.
27.
N. Neumann, S. Kurth, K. Hiller. “Tunable Infrared Detector with Integrated Micromachined Fabry–Perot Filter”. Proc. SPIE 6466, MOEMS and Miniaturized Systems VI, 646606 (22 January 2007). DOI: 10.1117/12.698871.
28.
P.M. Moselund, L. Huot, C.D. Brooks. “All-Fiber Mid-IR Supercontinuum: A Powerful New Tool for IR-Spectroscopy”. Proceedings Volume 9703, Optical Biopsy XIV: Toward Real-Time Spectroscopic Imaging and Diagnosis. 2016. 97030B. DOI: 10.1117/12.2213129.
29.
P. Moselund, C. Petersen, L. Leick, J. Seidelin Dam, et al. “Highly Stable, All-fiber, High Power ZBLAN Supercontinuum Source Reaching 4.75 µm Used for Nanosecond Mid-IR Spectroscopy”. Paper presented at: Advanced Solid-State Lasers Congress. Paris, France, 27 October–1 November 2013. P. JTh5A.9.
P.R. Griffiths, J.A. De Haseth. Fourier Transform Infrared Spectrometry. Hoboken, NJ: Wiley-Interscience, 2007.
35.
MichaelsC.A.MasielloT.ChuP.M.“Fourier Transform Spectrometry with a Near Infrared Supercontinuum Source”. Appl. Spectrosc. 2009. 63(5): 538–543.
36.
RamsayJ.DupontS.KeidingS.R.“Pulse-to-Pulse Noise Reduction in Infrared Supercontinuum Spectroscopy: Polarization and Amplitude Fluctuations”. Laser Phys. Lett. 2014. 11(9): 95702.
37.
AllanD.W.“Statistics of Atomic Frequency Standards”. Proc. IEEE. 1966. 54(2): 221–230.
38.
WerleP.MückeR.SlemrF.“The Limits of Signal Averaging in Atmospheric Trace-Gas Monitoring by Tunable Diode-Laser Absorption Spectroscopy (TDLAS)”. Appl. Phys. B: Photophys. Laser Chem. 1993. 57(2): 131–139.
39.
BrownW.J.KimS.WaxA.“Noise Characterization of Supercontinuum Sources for Low-Coherence Interferometry Applications”. J. Opt. Soc. Am. A. 2014. 31(12): 2703–10.
40.
ThéorêtA.SandorfyC.“Infrared Spectra and Crystalline Phase Transitions of Ammonium Nitrate”. Can. J. Chem. 1964. 42(1): 57–62.
41.
ChalmersJ.M.GriffithsP.R.Handbook of Vibrational Spectroscopy, New York: John Wiley and Sons, 2002.
