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南京工程学院毕业设计文献资料翻译（原文及译文）原文名称：Infrared课题名称：基于单片机的防盗报警器的设计与实现学生姓名：常小军学号：240082410指导老师：沙爱军所在院系：康尼学院专业名称：通信工程2011年3月南京InfraredInfrared(IR)lightiselectromagneticradiationwithawavelengthlongerthanthatofvisiblelight,measuredfromthenominaledgeofvisibleredlightat0.74micrometres(µm),andextendingconventionallyto300µm.Thesewavelengthscorrespondtoafrequencyrangeofapproximately1to400THz,[1]andincludemostofthethermalradiationemittedbyobjectsnearroomtemperature.Microscopically,IRlightistypicallyemittedorabsorbedbymoleculeswhentheychangetheirrotational-vibrationalmovements.Infraredlightisusedinindustrial,scientific,andmedicalapplications.Night-visiondevicesusinginfraredilluminationallowpeopleoranimalstobeobservedwithouttheobserverbeingdetected.Inastronomy,imagingatinfraredwavelengthsallowsobservationofobjectsobscuredbyinterstellardust.Infraredimagingcamerasareusedtodetectheatlossininsulatedsystems,observechangingbloodflowintheskin,andoverheatingofelectricalapparatus.MuchoftheenergyfromtheSunarrivesonEarthintheformofinfraredradiation.Sunlightatzenithprovidesanirradianceofjustover1kilowattpersquaremeteratsealevel.Ofthisenergy,527wattsisinfraredradiation,445wattsisvisiblelight,and32wattsisultravioletradiation.[2]ThebalancebetweenabsorbedandemittedinfraredradiationhasacriticaleffectontheEarth'sclimate.Objectsgenerallyemitinfraredradiationacrossaspectrumofwavelengths,butsometimesonlyalimitedregionofthespectrumisofinterestbecausesensorsusuallycollectradiationonlywithinaspecificbandwidth.Therefore,theinfraredbandisoftensubdividedintosmallersections.Heat/Heating[5]Infraredradiationispopularlyknownasheatradiation,butlightandelectromagneticwavesofanyfrequencywillheatsurfacesthatabsorbthem.InfraredlightfromtheSunonlyaccountsfor49%[4]oftheheatingoftheEarth,withtherestbeingcausedbyvisiblelightthatisabsorbedthenre-radiatedatlongerwavelengths.Visiblelightorultraviolet-emittinglaserscancharpaperandincandescentlyhotobjectsemitvisibleradiation.Objectsatroomtemperaturewillemitradiationmostlyconcentratedinthe8to25µmband,butthisisnotdistinctfromtheemissionofvisiblelightbyincandescentobjectsandultravioletbyevenhotterobjects(seeblackbodyandWien'sdisplacementlaw)[5].Heatisenergyintransientformthatflowsduetotemperaturedifference.Unlikeheattransmittedbythermalconductionorthermalconvection,radiationcanpropagatethroughavacuum.Theconceptofemissivityisimportantinunderstandingtheinfraredemissionsofobjects.Thisisapropertyofasurfacewhichdescribeshowitsthermalemissionsdeviatefromtheidealofablackbody.Tofurtherexplain,twoobjectsatthesamephysicaltemperaturewillnotappearthesametemperatureinaninfraredimageiftheyhavedifferingemissivities.Thermography[6]Infraredradiationcanbeusedtoremotelydeterminethetemperatureofobjects(iftheemissivityisknown).Thisistermedthermography,orinthecaseofveryhotobjectsintheNIRorvisibleitistermedpyrometry.Thermography(thermalimaging)ismainlyusedinmilitaryandindustrialapplicationsbutthetechnologyisreachingthepublicmarketintheformofinfraredcamerasoncarsduetothemassivelyreducedproductioncosts.Thermographic[8]camerasdetectradiationintheinfraredrangeoftheelectromagneticspectrum(roughly900–14,000nanometersor0.9–14μm)andproduceimagesofthatradiation.Sinceinfraredradiationisemittedbyallobjectsbasedontheirtemperatures,accordingtotheblackbodyradiationlaw,thermographymakesitpossibletoseeone'senvironmentwithorwithoutvisibleillumination.Theamountofradiationemittedbyanobjectincreaseswithtemperature,thereforethermographyallowsonetoseevariationsintemperature(hencethename).Infraredradiationcanbeusedasadeliberateheatingsource.Forexampleitisusedininfraredsaunastoheattheoccupants,andalsotoremoveicefromthewingsofaircraft(de-icing).FIRisalsogainingpopularityasasafeheattherapymethodofnaturalhealthcare&physiotherapy.Infraredcanbeusedincookingandheatingfoodasitpredominantlyheatstheopaque,absorbentobjects,ratherthantheairaroundthem.Infraredheatingisalsobecomingmorepopularinindustrialmanufacturingprocesses,e.g.curingofcoatings,formingofplastics,annealing,plasticwelding,printdrying.Intheseapplications,infraredheatersreplaceconvectionovensandcontactheating.Efficiencyisachievedbymatchingthewavelengthoftheinfraredheatertotheabsorptioncharacteristicsofthematerial.Climatology[6]Inthefieldofclimatology,atmosphericinfraredradiationismonitoredtodetecttrendsintheenergyexchangebetweentheearthandtheatmosphere.ThesetrendsprovideinformationonlongtermchangesintheEarth'sclimate.Itisoneoftheprimaryparametersstudiedinresearchintoglobalwarmingtogetherwithsolarradiation.Apyrgeometerisutilizedinthisfieldofresearchtoperformcontinuousoutdoormeasurements.Thisisabroadbandinfraredradiometerwithsensitivityforinfraredradiationbetweenapproximately4.5µmand50µm.NightvisionInfraredisusedinnightvisionequipmentwhenthereisinsufficientvisiblelighttosee.Nightvisiondevicesoperatethroughaprocessinvolvingtheconversionofambientlightphotonsintoelectronswhicharethenamplifiedbyachemicalandelectricalprocessandthenconvertedbackintovisiblelight.[5]Infraredlightsourcescanbeusedtoaugmenttheavailableambientlightfor