{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T18:11:16Z","timestamp":1774030276991,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,1,21]],"date-time":"2020-01-21T00:00:00Z","timestamp":1579564800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51676105"],"award-info":[{"award-number":["51676105"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["11972213"],"award-info":[{"award-number":["11972213"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51906120"],"award-info":[{"award-number":["51906120"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Key R&amp;D Program of China","award":["2016YFC0201104"],"award-info":[{"award-number":["2016YFC0201104"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A wide-range, calibration-free tunable diode laser spectrometer is established by combining wavelength modulation and direct absorption spectroscopy (WM-DAS) with continuous wave cavity ringdown spectroscopy (CW-CRDS). This spectrometer combines the benefits of absolute concentration measurements, wide range, and high speed, using WM-DAS with enhanced noise reduction in CW-CRDS. The accurate baseline ringdown time, \u03c40, is calculated by the absorption peak (measured by WM-DAS) and the ringdown time containing gas absorption information (measured by CW-CRDS at the center wavelength of the spectral line). The gas concentration is obtained without measuring \u03c40 in real time, thus, greatly improving the measuring speed. A WM-DAS\/CW-CRDS spectrometer at 1.57 \u03bcm for CO detection was assembled for experimental validation of the multiplexing scheme over a concentration ranging from 4 ppm to 1.09% (0.1 MPa, 298 K). The measured concentration of CO at 6374.406 cm\u22121 shows that the dynamic range of this tunable diode laser absorption spectrometer is extendable up to five orders of magnitude and the corresponding precision is improved. The measurement speed of this spectrometer can extend up to 10 ms, and the detection limit can reach 35 ppb within 25 s.<\/jats:p>","DOI":"10.3390\/s20030585","type":"journal-article","created":{"date-parts":[[2020,1,21]],"date-time":"2020-01-21T11:25:59Z","timestamp":1579605959000},"page":"585","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["A Wide-Range and Calibration-Free Spectrometer Which Combines Wavelength Modulation and Direct Absorption Spectroscopy with Cavity Ringdown Spectroscopy"],"prefix":"10.3390","volume":"20","author":[{"given":"Zhen","family":"Wang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Power Systems, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanjun","family":"Du","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Power Systems, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanjun","family":"Ding","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Power Systems, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhimin","family":"Peng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Power Systems, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2428","DOI":"10.1364\/OL.38.002428","article-title":"Time-resolved tunable diode laser absorption spectroscopy of pulsed plasma","volume":"38","author":"Kment","year":"2013","journal-title":"Opt. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"132","DOI":"10.1016\/j.pecs.2016.12.002","article-title":"Infrared laser-absorption sensing for combustion gases","volume":"60","author":"Goldenstein","year":"2017","journal-title":"Prog. Energy Combust."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3653","DOI":"10.1016\/j.proci.2014.06.038","article-title":"Calibration-free, high-speed, in-cylinder laser absorption sensor for cycle-resolved, absolute H2O measurements in a production IC engine","volume":"35","author":"Witzel","year":"2015","journal-title":"Proc. Combust. Inst."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"111124","DOI":"10.1117\/1.3498782","article-title":"Wood E Application of quantum cascade lasers to high-precision atmospheric trace gas measurements","volume":"49","author":"McManus","year":"2010","journal-title":"Opt. Eng."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1007\/s00340-015-6033-0","article-title":"Recent progress in laser-based trace gas instruments: Performance and noise analysis","volume":"119","author":"McManus","year":"2015","journal-title":"Appl. Phys. B"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Zhao, G., Tan, W., Jia, M., Hou, J., Ma, W., Dong, L., Zhang, L., Feng, X., Wu, X., and Yin, W. (2016). Intensity-stabilized fast-scanned direct absorption spectroscopy instrumentation based on a distributed feedback laser with detection sensitivity down to 4 \u00d7 10\u22126. Sensors, 16.","DOI":"10.3390\/s16091544"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"7570","DOI":"10.3390\/s130607570","article-title":"Aspects of the Application of Cavity Enhanced Spectroscopy to Nitrogen Oxides Detection","volume":"13","author":"Wojtas","year":"2013","journal-title":"Sensors"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"3300","DOI":"10.1364\/OL.35.003300","article-title":"Optical parametric oscillator based off-axis integrated cavity output spectroscopy for rapid chemical sensing","volume":"35","author":"Arslanov","year":"2010","journal-title":"Opt. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"467","DOI":"10.1007\/s00340-008-3137-9","article-title":"Design considerations in high-sensitivity off-axis integrated cavity output spectroscopy","volume":"92","author":"Moyer","year":"2008","journal-title":"Appl. Phys. B"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1016\/S0009-2614(96)01351-6","article-title":"CW cavity ring down spectroscopy","volume":"264","author":"Romanini","year":"1997","journal-title":"Chem. Phys. Lett."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3154","DOI":"10.1364\/AO.39.003154","article-title":"Doppler-free nonlinear absorption in ethylene by use of continuous-wave cavity ring down spectroscopy","volume":"39","author":"Bucher","year":"2000","journal-title":"Appl. Opt."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"4599","DOI":"10.1021\/ac0343073","article-title":"Trace moisture detection using continuous-wave cavity ring-down spectroscopy","volume":"75","author":"Dudek","year":"2003","journal-title":"Anal. Chem."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"511","DOI":"10.5194\/amt-6-511-2013","article-title":"Long-term greenhouse gas measurements from aircraft","volume":"6","author":"Karion","year":"2013","journal-title":"Atmos. Meas. Tech."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1007\/s00340-012-5242-z","article-title":"Absolute, spatially resolved, in situ CO profiles in atmospheric laminar counter-flow diffusion flames using 2.3 \u03bcm TDLAS","volume":"109","author":"Wagner","year":"2012","journal-title":"Appl. Phys. B"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1453","DOI":"10.1016\/j.proci.2018.06.182","article-title":"In situ sensor for cycle-resolved measurement of temperature and mole fractions in IC engine exhaust gases","volume":"37","author":"Diemel","year":"2019","journal-title":"Proc. Combust. Inst."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"095013","DOI":"10.1088\/1361-6595\/aadf01","article-title":"HO2 reaction kinetics in an atmospheric pressure plasma jet determined by cavity ring-down spectroscopy","volume":"27","author":"Gianella","year":"2018","journal-title":"Plasma Sources Sci. Technol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1612","DOI":"10.1364\/OL.41.001612","article-title":"Ultra-sensitive cavity ring down spectroscopy in the mid-infrared spectral region","volume":"41","author":"Long","year":"2016","journal-title":"Opt. Lett."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"29086","DOI":"10.1364\/OE.26.029086","article-title":"Step-modulated decay cavity ring-down detection for double resonance spectroscopy","volume":"26","author":"Karhu","year":"2018","journal-title":"Opt. Express"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5523","DOI":"10.1364\/OE.24.005523","article-title":"Open-path cavity ring-down spectroscopy for trace gas measurements in ambient air","volume":"24","author":"McHale","year":"2016","journal-title":"Opt. Express"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5408","DOI":"10.1364\/AO.46.005408","article-title":"Simple, stable, and compact multiple-reflection optical cell for very long optical paths","volume":"46","author":"Robert","year":"2007","journal-title":"Appl. Opt."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"105702","DOI":"10.1088\/1555-6611\/aad0d8","article-title":"A continuous-wave quantum cascade laser near 7.5 \u03bcm combined with 2f-wavelength modulation spectroscopy for trace monitoring of ambient CH4 concentrations","volume":"28","author":"Pal","year":"2018","journal-title":"Laser Phys."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1767","DOI":"10.5194\/amt-12-1767-2019","article-title":"Adaptation and performance assessment of a quantum and interband cascade laser spectrometer for simultaneous airborne in situ observation of CH4, C2H6, CO2, CO and N2O","volume":"12","author":"Kostinek","year":"2019","journal-title":"Atmos. Meas. Tech."},{"key":"ref_23","first-page":"811","article-title":"Recovery of absolute gas absorption line shapes using tunable diode laser spectroscopy with wavelength modulation-part 1: Theoretical analysis","volume":"29","author":"Stewart","year":"2011","journal-title":"J. Lightwave Technol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"23724","DOI":"10.1364\/OE.21.023724","article-title":"First harmonic with wavelength modulation spectroscopy to measure integrated absorbance under low absorption","volume":"21","author":"Peng","year":"2013","journal-title":"Opt. Express"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"543","DOI":"10.1007\/s00340-014-5866-2","article-title":"Multi-harmonic measurements of line shape under low absorption conditions","volume":"117","author":"Lan","year":"2014","journal-title":"Appl. Phys. B"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"21497","DOI":"10.3390\/s141121497","article-title":"Rapid, Time-Division Multiplexed, Direct Absorption- and Wavelength Modulation-Spectroscopy","volume":"14","author":"Klein","year":"2014","journal-title":"Sensors"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1911","DOI":"10.5194\/amt-10-1911-2017","article-title":"Evaluation of the accuracy of thermal dissociation CRDS and LIF techniques for atmospheric measurement of reactive nitrogen species","volume":"10","author":"Womack","year":"2017","journal-title":"Atmos. Meas. Tech."},{"key":"ref_28","first-page":"131","article-title":"Intercomparison of in situ CRDS and CEAS for measurements of atmospheric N2O5 in Beijing, China","volume":"613\u2013614","author":"Li","year":"2018","journal-title":"Sci. Total Environ."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"9263","DOI":"10.1364\/OE.26.009263","article-title":"Wavelength modulation spectroscopy for recovering absolute absorbance","volume":"26","author":"Du","year":"2018","journal-title":"Opt. Express"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/j.jqsrt.2018.11.014","article-title":"Measurements of spectroscopic parameters of CO2 transitions for Voigt, Rautian, galatry and speed-dependent voigt profiles near 1.43 \u03bcm using the WM-DAS method","volume":"224","author":"Li","year":"2019","journal-title":"J. Quant. Spectrosc. Radiat. Transf."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"29550","DOI":"10.1364\/OE.26.029550","article-title":"High-accuracy sinewave-scanned direct absorption spectroscopy","volume":"26","author":"Du","year":"2018","journal-title":"Opt. Express"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"704","DOI":"10.1364\/OL.32.000704","article-title":"Precise multipass Herriott cell design: Derivation of controlling design equations","volume":"32","author":"Engel","year":"2007","journal-title":"Opt. Lett."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1007\/s00340-005-1834-1","article-title":"Fast Fourier transform analysis in cavity ring-down spectroscopy: Application to an optical detector for atmospheric NO2","volume":"81","author":"Mazurenka","year":"2005","journal-title":"Appl. Phys. B"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1016\/j.jqsrt.2014.11.008","article-title":"Diode-laser measurements of linestrength and temperature-dependent lineshape parameters for H2O transitions near 1.4\u03bcm using Voigt, Rautian, Galatry, and speed-dependent Voigt profiles","volume":"152","author":"Goldenstein","year":"2015","journal-title":"J. Quant. Spectrosc. Radiat. Transf."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"A74","DOI":"10.1364\/AO.50.000A74","article-title":"Dual quantum cascade laser trace gas instrument with astigmatic Herriott cell at high pass number","volume":"50","author":"McManus","year":"2011","journal-title":"Appl. Opt."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1109\/PROC.1966.4634","article-title":"Statistics of Atomic Frequency Standards","volume":"54","author":"Allan","year":"1966","journal-title":"Proc. IEEE"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1016\/j.jqsrt.2017.06.034","article-title":"Line shape parameters of helium-broadened 12C16O transitions in the 3\u21920 overtone band near 1.57 \u03bcm","volume":"203","author":"Reed","year":"2017","journal-title":"J. Quant. Spectrosc. Radiat. Transf."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1016\/j.jqsrt.2017.03.001","article-title":"Spectral shapes of rovibrational lines of CO broadened by He, Ar, Kr and SF6: A test case of the Hartmann-Tran profile","volume":"203","author":"Ngo","year":"2017","journal-title":"J. Quant. Spectrosc. Radiat. Transf."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1366\/10-06074","article-title":"Simultaneous Measurements of CO2 and CO Using a Single Distributed-Feedback (DFB) Diode Laser Near 1.57 \u03bcm at Elevated Temperatures","volume":"65","author":"Cai","year":"2011","journal-title":"Appl. Spectrosc."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"723","DOI":"10.1016\/j.snb.2016.03.089","article-title":"Simultaneous atmospheric CO, N2O and H2O detection using a singlequantum cascade laser sensor based on dual-spectroscopy techniques","volume":"231","author":"Li","year":"2016","journal-title":"Sensor Actuat. B Chem."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/3\/585\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T13:20:28Z","timestamp":1760361628000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/3\/585"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,1,21]]},"references-count":40,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2020,2]]}},"alternative-id":["s20030585"],"URL":"https:\/\/doi.org\/10.3390\/s20030585","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,1,21]]}}}