甲烷红外吸收光谱原理与处理技术分析

28,11Vol128,No111,pp251522519200811SpectroscopyandSpectralAnalysisNovember,2008,3,,,,,,130012,,,2+2323,,,3,;;;;:O65713:ADOI:1013964/j1issn1100020593(2008)1122515205:2007206228,:2007209229:(60477012):,1982,e2mail:[e-mail]3e2mail:[e-mail],,5%,15%,918%20min,[1],,1530,15%1%[2][3],,2070[4],[5],,1111,,,CH44,4,4:1=291310cm-1,2=153313cm-1,3=301819cm-1,4=130519cm-1,3143,6153,3131,7166m13131mFig11AbsorptionspectraofCH4near3131m,1983,TohokuInGaAsPLED2+23,1133mQ,113312m[6]1984,CH423,1166mQ3nm,116654m[7]211661133mFig12AbsorptionspectraofCH4near1166and1133m,3131m11331166m1300160,,1166m,112,Beer2Lambert,II0I=I0e-[g()CL+()](1),c,L,(),g()CH4,,g()=g01+-0()2(2),02,,,,,,,,CH4,211:,,;,,,3Nagali[8]InGaAsPLD100mA100Hz,InGaAsPLD11646m,20cm,,GeA;GeB,300K,CH451010-5Fig13Schematicofsingle2wavelengthanddual2beampathdifferentialsystem,4[9]InGaAsPLED(1161m,80nm)100Hz,,,Ge,,2km,10-4Fig14Schematicofdual2wavelengthandsinglebeampathdifferentialsystem,C=C0Lln1t(3),C0,L,t,,,5,[10]DFBLD(InGaAsP/InP:1165m),()012nm,,,10kHz61522811atm60%40%A,2B,InGaAspin,0;,,,41010-6Fig15Schematicofdual2wavelengthanddual2beampathdifferentialsystem212(WMS),,,,(2),,,[11](DFBLD),,6[12]1166mDFBLD,5135MHz50cm1cm,1atm/InGaAsp2i2n,,,2,22[13]R21=I2I=01343CLg0m(4),,1,31010-7Fig16SchematicofharmonicmeasurementsystemwithDFBLDLED7LEDF2P[14],LED1164m,50nm(2015m),500mF2P1kHz,d=d0+dxsintF2PI(d)=I0(1-R)/(1+R)-CiIi/[1+Fsin2(i+Xisint)](5)1kHz,2kHz,I2/Idc,1%,2%,5%,10%,20%,50%,,0102%LEL,11010-5Fig17SchematicofharmonicmeasurementsystemwithLEDandF2P213,,,1942White,White[15],83,,S/N12(n+1)Rn/2(6)n,RDoussin1999White,[16],31010-811010-7Fig18Whitecavityschematicdiagram715211,(CEAS)(ICOS),,,[17]II01-R21-L1-R(7)9[18]M1M2,,,30GHz,2030Hz1166m,,61010-7Fig19SchematicofthemeasurementsystemforICOSRingdown(CRDS),Keefe[19],,(Ringdown),=Lc1L-lnR(8),RRingdown,10DFBLD[20],16mW815m,,Ringdown0193s,21510-10Fig110SchematicofthemeasurementsystemforCRDS214(PAS),,,,PASPASRc,RmW()U()=RmRcW()(9)11[21]PAS,,PAS,10cm,5cm10cm2mm,315Hz2,,101Hz(10-3,10-4,210-6):1165m23,11510-7;719m4,31010-9Fig111SchematicofthemeasurementsystemforPAS3(1),,,,,,,,,,,(2),,,(3),815228[1]FranksAR,OptermanJJ,FrielFG,etal.USDepartmentofHealthandHumanServices,ReportofInestigations9640.1997.[2]FrishBM,WainnerTR,EvansSJ,etal.QuantumElectronicsandLaserScienceConference(QELS),2005,3:1941.[3]RellaR,SicilianoP,VasanelliL.J.Appl.Phys.,1998,83(4):2369.[4]InabaH,KobayasiT,HiratnaM.ElectronicsLetters,1979,23:749.[5]KosterevAA,TittlelKF.IEEEJournalofQuantumElectronics,2002,38(6):582.[6]ChanK,ItoH,InabaH.AppliedOptics,1983,22(23):3802.[7]ChanK,ItoH,InabaH.IEEE/OSA.J.Light2WaveTechnol.1984,LT22:234.[8]NagaliV,ChouIS,BaerSD,etal.AppliedOptics,1996,35(21):4026.[9]ChanK,ItoH,InabaH.AppliedOptics,1984,23(19):3415.[10]ShimoseY,OkamotoT,MaruyamaA,etal.IEEEPhotonicsTechnologyLetters,1991,3(1):86.[11]WANGShi2mei,LIUWen2qing,LIUJian2guo,etal(,,,).SpectroscopyandSpectralAnalysis(),2006,26(2):221.[12]UeharaK,TaiH.AppliedOptics,1992,31(6):809.[13]JinW.AppliedOptics,1999,38(29),5290.[14]JinW,StewartG,CulshawB.OpticsLetters,1993,18(16):1364.[15]WhiteUJ.JournalofOpt.Soc.Am.,1942,32:285.[16]DoussinFJ,DominiqueR,PatrickC.AppliedOptics,1999,38(19):4145.[17]BakhirkinAY,KosterevAA,RollerC,etal.AppliedOptics,2004,43(11):2257.[18]BarryRH,CornerL,HancockG,etal.ChemicalPhysicsLetters,2001,333:285.[19]OKeefeA,DeaconGAD.ReviewofScientificInstruments,1988,59:2544.[20]PaldusAB,HarbCC,SpenceGT,etal.Opt.Lett.,2000,25(9):666.[21]GrosselA,ZeninariV,JolyL,etal.SpectrochimicaActaPartA,2006,63:1021.ThePrincipleandTechnicalAnalysisofMethaneDetectionUsingInfraredAbsorptionSpectroscopyZHANGYu,WANGYi2ding3,LILi,ZHENGChuan2tao,ANYu2peng,SONGZhen2yuStateKeyLaboratoryofIntegratedOptoelectronics,JilinUniversityRegion,CollegeofElectronicScienceandEngineering,JilinUniversity,Changchun130012,ChinaAbstractTherehasbeenconsiderableinterestrecentlyinmethanesensorbasedoninfraredabsorptionspectroscopyforindustri2aldetectionandenvironmentmonitoring.Thepresentpaperpresentstheintensitesofmethanemid2infraredfundamentalabsorp2tionbands,near2infraredcombinationbandof2+23andovertonebandof23,anditwasfoundthattheabsorptionstrengthsoffundamentalbandsaretwoordersofmagnitudehigherthanthoseofovertonebandsandthreeordersofmagnitudehigherthanthoseofthecombinations.Theoretically,mid2infrareddetectionsystemismuchbetter.However,becausethenear2infraredsourceanddetectoraremorematurelydevelopedandcheaper,near2infraredtechnologyiswidelyused.Furthermore,thenear2infraredradiationcanbetransmittedthroughordinarylow2losssilicafiber,suitableforlong2distancemethanesensingsystem,meetingtheneedsofindustrialminingandotheraspects.Butwiththedevelopmentofmid2infrareddetectorandhigh2powerhigh2sensitivitydevices,lowpricedmicrosensormoduleswillbemoreandmoredeveloped.Thedevelopmentofopticalmethanesen2sorsisreportedinthispaper.Severaldetectiontechnologieswereinvestigatedsuchasdifferentialabsorption,harmonicdetec2tion,cavityspectroscopyenhancementandphotoacousticspectroscopy.Thetheoreticalformula,sensitivityandsystemstru