第1題Weusethetermoptictorefertofrequenciesintheinfrared,visible,andultravioletportionsofthespectrum.Visiblewavelengthsextend______.Afrom0.4micrometerto0.7micrometerBfrom0.4micrometerto0.85micrometerCfrom0.7micrometerto0.85micrometerDfrom1.26micrometerto1.75micrometer第2題Theadventoflampsallowedtheconstructionofsimpleoptic-communicationssystems,anytypeof()isbasicallyanoptic-communicationssystem.AlampBindicatorlampClaserDneonlamp第3題Itwasnotuntil1970thatthefirsttruly()wasdevelopedandfiberopticcommunicationsbecamepractical.AfiberBlow-lossfiberCplasticfiberDmultimodefiber第4題Digitalmodulationinvolvestransmittinginformationindiscreteform.()第5題Inanycase,theinformationmustbeinopticalformbeforetransmissionforeitherelectronicoropticalcommunications.()第6題Assumingthatthelossofthesystemis-3dBandtheinputpoweris5mW,theoutputpoweris2mW.()第7題Inwhichphenomenondoestheparticlenatureoflightmanifest?AInterferenceanddiffractionBPhotoelectriceffectCBraggscatteringDPropagationofelectromagneticwaves第8題Inwhichphenomenondoestheparticlenatureoflightmanifest?AInterferenceanddiffractionBComptonscatteringCBraggscatteringDDeviationinamagneticfield第9題Inanexperiment,abeamoflightpassesthroughanarrowslit,formingadistinctinterferencepattern.Basedonthisobservation,lLightisaparticlebecauseonlyparticlescanforminterferencepatternswhenpassingthroughanarrowslit.第10題Theparticlenatureandwavenatureoflightaremutuallyexclusive第1題Whichofthefollowingbestdefinesmonochromaticwave?AAwavewithonlyonewavelengthBAwavewithonlyonefrequencyCAwavewithonlyonephasevelocityDAwavewithonlyoneamplitude第2題Whichofthefollowingstatementsaboutelectromagneticwavesistrue?AElectromagneticwavestravelfasterinavacuumthaninamedium.BElectromagneticwavestravelslowerinavacuumthaninamedium.CElectromagneticwavestravelatthesamespeedinavacuumasinamedium.DElectromagneticwavescannottravelthroughavacuumoramedium.第3題Whichofthefollowingstatementsistrueaboutlight?ALightisaparticlethatexhibitswave-likebehavior.BLightisawavethatdoesnothaveaparticlenature.CLightisaparticlethatdoesnothaveawavenature.DLightisneitheraparticlenorawave.第4題____isafringeininterferencepattern.AAdarkstripewheretwolightwavescanceleachotherout.BAbrightstripewheretwolightwavesoverlapandreinforceeachother.CAstripewherelightdiffractsoffanobstacle.DAstripewherelightreflectsoffamirror-likesurface.第5題Whatistheeffectofreflectiononthepolarizationstateoflight_____?AReflectiondoesnotchangethepolarizationstateoflightBReflectionchangesthepolarizationstateoflighttofullypolarizedCReflectionchangesthepolarizationstateoflighttopartiallypolarizedDReflectionchangesthepolarizationstateoflighttounpolarized第6題_____istheeffectofpassingunpolarizedlightthroughapolarizer?AThelightbecomesfullypolarizedinonedirectionBThelightremainsunpolarizedCTheintensityofthelightincreasesDThecolorofthelightchanges第7題_____WhatisBrewsterangle.ATheangleatwhichreflectedlightbecomesfullypolarizedBTheangleatwhichreflectedlightremainsunpolarizedCTheangleatwhichreflectedlightbecomespartiallypolarizedDNoneoftheabove第8題Whathappenstothepolarizationstateoflightwhenitreflectsfromasurface_____?AItremainsunchangedBItbecomesfullypolarizedCItbecomespartiallypolarizedDItbecomesunpolarized第9題Whatistherelationshipbetweentheamplitudeandphaseoftheelectricfieldcomponentsforcircularlypolarizedlight_____?AEqualamplitudeandaphasedifferenceofπ/2or3π/2BEqualamplitudeandaphasedifferenceofπ/4or5π/4CEqualamplitudeandnophasedifferenceDNoneoftheabove第10題Whatisthepolarizationstateoflightwhentheellipseisacircle_____?ALinearpolarizationBCircularpolarization.CEllipticalpolarizationDNoneoftheaboveAnswer:第11題_____determinestheshapeoftheellipse?AAmplitudeoftheelectricfieldcomponentsBPhasedifferencebetweentheelectricfieldcomponentsCPhasedifferenceandamplitudeoftheelectricfieldcomponentsDNoneoftheabove第12題_____istheshapeoftheellipsethatrepresentsthepolarizationstateoflight.ACircleBTriangleCEllipseDRectangle第13題Howcanpolarizedlightbedecomposed_____?AIntoxandycomponentsBIntolinearandcircularcomponentsCIntoincoherentandcoherentcomponentsDIntounpolarizedandpolarizedcomponents第14題Whatdoesunpolarizedlightmean_____?ALightwitharandompolarizationstateBLightwithallelectricfieldcomponentsoscillatinginthesamedirectionCLightwithallelectricfieldcomponentsoscillatingindifferentdirectionsDLightwithnoelectricfieldcomponents第15題Whentwocoherentlightbeamsinterfere,______istypicallyobserved?ADiffractionpatternBInterferencepatternCReflectionpatternDTransmissionpattern第16題______istheprinciplebehindtheformationofinterferencefringesinaninterferometer?ADiffractionoflightbytheinterferometer'smirrorsBInteractionoflightwithmatterintheinterferometerCSuperpositionofwavesfromdifferentsourcesDPolarizationoflightintheinterferometer第17題______determinesthecolorofthefringesinadouble-slitinterferencepattern.AThedistancebetweentheslitsBThewavelengthofthelightCTheintensityofthelightsourceDThedistancebetweentheslitsandtheobservationscreen第18題Whichofthefollowingbestdescribesdiffraction______?AWhenlightencountersobstacles,itfollowsthestraightestpathpossible.BWhenlightencountersobstacles,itdeviatesfromtheoriginaldirectionandspreadsintotheshadowarea.CWhenlightencountersobstacles,itreflectsofftheminamirror-likemanner.DWhenlightencountersobstacles,itpassesthroughthemwithoutanychangeindirection.第19題Whatisthedistancefromtheslitstotheobservationscreeninaninterferenceexperiment______?AItshouldbeassmallaspossibletoobserveinterferencefringesclearly.BItshouldbegreaterthanthedistancebetweentheslitstoobserveinterferencefringesclearly.CItshouldbeequaltothedistancebetweentheslitstoobserveinterferencefringesclearly.DItdoesn'tmatteraslongasthescreenisplacedperpendiculartothepropagationdirectionoflightbeamsfromtheslits.第20題______isthedifferencebetweeninterferenceanddiffraction?AInterferenceoccurswhenwavessuperimpose,whilediffractionoccurswhenwavesencounterobstacles.BInterferenceisconcernedwiththepathoflightrays,whilediffractionisconcernedwiththebehavioroflightwaves.CInterferenceproducespatternsofconstructiveanddestructiveinterference,whilediffractionproducesunevenintensitydistributioninboththeshadowandgeometricilluminationareas.DInterferenceisconcernedwiththephaseoflightwaves,whilediffractionisconcernedwiththeamplitudeoflightwaves.第21題______isthedifferencebetweenclassicalgeometricopticsandwaveoptics.AClassicalgeometricopticsassumeslightbehavesasparticles,whilewaveopticsassumeslightbehavesaswaves.BClassicalgeometricopticsfocusesonthepathoflight,whilewaveopticsfocusesonthebehavioroflightwaves.CClassicalgeometricopticsignoresdiffractioneffects,whilewaveopticstakesthemintoaccount.DClassicalgeometricopticsassumeslightbehavesaswaves,whilewaveopticsassumeslightbehavesasparticles.第22題Whatistherelationshipbetweeninterferenceanddiffraction______?ATheyarethesamephenomenon.BTheyarecompletelydifferentphenomena.CInterferenceisaspecialcaseofdiffraction.DDiffractionisaspecialcaseofinterference.第23題_____isNOTawaveopticalphenomenon?AInterferenceBDiffractionCReflectionDTransmission第24題Whichstatementbestdescribesthewave-particledualityoflight?______ALightbehavesasawaveinsomeexperimentsandasaparticleinothers.BLightiseitherawaveoraparticle,dependingonthecontext.CLightcannotexhibitbothwaveandparticlepropertiessimultaneously.DLightisneitherawavenoraparticle,butratheraquantumentity.第25題Howdoopticallensesworkaccordingtotheelectromagnetictheoryoflight?______ATheyscatterlightwavesrandomlyinalldirectionstoformanimageonascreenoreyeretina.BTheyrefractlightwavesusingtherefractiveindexdifferencebetweenairandglasstoformanimageonascreenoreyeretina.CTheydiffractlightwavesusingdiffractiongratingstoformanimageonascreenoreyeretina.DTheyabsorblightwavescompletelytoformanimageonascreenoreyeretina.第26題Whatistherelationshipbetweenthephasevelocityandgroupvelocityoflightwaves?______AThephasevelocityisalwaysgreaterthanthegroupvelocity.BThephasevelocityisalwayslessthanthegroupvelocity.CThephasevelocityandgroupvelocityareequaltoeachother.DThereisnorelationshipbetweenthephasevelocityandgroupvelocity.第27題Whatistherelationshipbetweenwavelengthandfrequencyofelectromagneticwavesaccordingtotheelectromagnetictheoryoflight?______AWavelengthandfrequencyaredirectlyproportionaltoeachother.BWavelengthandfrequencyareinverselyproportionaltoeachother.CWavelengthandfrequencyhavenorelationshipwitheachother.DWavelengthandfrequencyvaryrandomlywitheachother.第28題Whichequationdescribesthepropagationofmonochromaticlightwaves?_____ASchrodingerequationBMaxwell'sequationsCHooke'slawDNewton'ssecondlaw第29題Whichofthefollowingbestdefinestherefractiveindexofanopticalmedium_____?ATheratioofthespeedoflightinvacuumtothespeedoflightinthemedium.BTheratioofthespeedoflightinthemediumtothespeedoflightinvacuum.CTheratioofthewavelengthoflightinvacuumtothewavelengthoflightinthemedium.DTheratioofthewavelengthoflightinthemediumtothewavelengthoflightinvacuum.第30題______isthespeedoflightinvacuumaccordingtotheelectromagnetictheory.A3x10^8m/sB3x10^6m/sC3x10^4m/sD3x10^2m/s第31題Makephotonspassthroughasingleslitonebyone,iftimeisenoughLong,diffractionpatternswillappearonthefilm第32題Afterasinglephotonpassesthroughasingleslit,completediffractionwillappearonthefilmShootingpattern第33題Theeffectsgeneratedbyalargenumberofphotonsoftenexhibitvolatility第34題Letphotonspassthroughtheslitonebyone,andeachphotonwillmoveuniformlyinastraightlineonthesameorbit第35題Thehigherthefrequencyoflight,theeasieritistoobservediffractionphenomena第36題Photonswithhigherenergyexhibitmoresignificantfluctuations.第37題Individualphotonsarepronetoexhibitingparticlelikebehavior,whilealargenumberofphotonsarepronetoexhibitingwavelikebehavior.第38題Waveparticledualityreferstothephenomenonwherelightsometimesexhibitswavelikebehaviorandsometimesexhibitsparticlelikebehavior.第39題Thehigherthefrequencyoflightwaves,themorepronouncedtheparticlenature.第40題Thereflectionenergyoflightindicatestheparticlenatureoflight第41題Undertheilluminationofafluorescentlamp,wecanobservecoloredstripesonthesurfaceoftwotightlysqueezedglasspanels,orthroughtheslitofapencilplacedtogether,wecanobservecoloredstripesonthefluorescentlamp.Thesetwophenomena().AAllareinterferencephenomenaoflightBAllarediffractionphenomenaoflightCTheformerisaninterferencephenomenon,whilethelatterisadiffractionphenomenonDTheformerisadispersionphenomenon,whilethelatterisaninterferencephenomenon第42題Whatisthecorrectunderstandingofthewaveparticledualityoflight?ATheeffectsofalargenumberofphotonsoftenexhibitwavelikebehavior,whilethebehaviorofindividualphotonsoftenexhibitsparticlelikebehaviorBLightisawavewhenitpropagates,butittransformsintoparticleswhenitinteractswithmatterCWaveparticledualityisthefundamentalpropertyoflight,sometimesitswavelikenatureissignificant,andsometimesitsparticlelikenatureissignificantDHighfrequencylightisparticles,lowfrequencylightiswaves正確答案：AC第43題Whichofthefollowingstatementsiscorrectintheexperimenttoverifythewaveparticledualityoflight?AMakephotonspassthroughtheslitonebyone,andifthetimeislongenough,diffractionpatternswillbedisplayedonthefilmBAfterasinglephotonpassesthroughaslit,acompletediffractionpatternwillappearonthefilmCThemotionpathofphotonsthroughslitsisastraightlineDThefluctuationoflightisalawofmotionforalargenumberofphotons正確答案：AD第44題Usinggreenlighttoirradiateaphotoelectrictubecanproduceaphotoelectriceffect.Toincreasethemaximuminitialkineticenergyofthephotoelectronwhenescapingfromthecathode?ASwitchtoredlightirradiationBIncreasetheintensityofgreenlightCIncreasetheaccelerationvoltageonthephotocellDSwitchtopurplelightirradiation第45題certainmetalsurfaceemitselectronswhenexposedtogreenlight,anddoesnotemitelectronswhenexposedtoyellowlight.Basedonthisfact,whichofthefollowinglightcanemitelectronswhenirradiatedonthemetalsurface?APurplelightBOrangelightCBluelightDRedlight正確答案：AC第46題Whichofthefollowingstatementsiscorrectaboutthenatureoflight?ARegardingthenatureoflight,Newtonproposedthe"particletheory",Huygensproposedthe"wavetheory",andEinsteinproposedthe"photontheory",bothofwhichexplainthenatureoflightBhewaveparticledualityoflightreferstothefactthatitcanbeviewedasbothmacroscopicwavesandmicroscopicparticlesCTheinterferenceanddiffractionphenomenaoflightindicatethatlighthaswavecharacteristicsDThephotoelectriceffectindicatesthatlighthasparticleproperties正確答案：CD第47題Whichofthefollowingstatementsiscorrectregardingthephotoelectriceffectcausedbyabeamofgreenlightshiningonacertainmetal?AIftheintensityofgreenlightisincreased,thenumberofphotoelectronsescapingperunittimeremainsunchangedBIftheintensityofgreenlightisincreased,themaximuminitialkineticenergyoftheemittedphotoelectronswillincreaseCIfpurplelightisusedforirradiation,themaximuminitialkineticenergyoftheemittedphotoelectronswillincreaseDIfpurplelightisusedinstead,thenumberofphotoelectronsescapingperunittimewilldefinitelyincrease第48題Whichofthefollowingstatementsiscorrect?APhotonsandphotoelectronsarethesametypeofparticleBWhenphotonsinteractwithparticlesofmatter,theynotonlyfollowtheconservationofenergy,butalsotheconservationofmomentumCLighthasbothparticleandwavecharacteristics,whichareprobabilitywaves,notelectromagneticwavesDMacroscopicobjectsalsohavewavecharacteristics,whicharemechanicalwaves第49題Thefirstpersontoprovetheparticlenatureoflightis().AEinsteinBNewtonCHuygensDGauss第50題Theparticletheoryoflightwasproposedby().AEinsteinBNewtonCHuygensDGaussTesting2第1題Thefiberopticlong-distancenetworkinChinaisashighasA58%B68%C88%D98%第2題Thefirstopticalfiberusedintransmissionsystemwasinventedin1970.第3題Therelativerefractiveindexdifferencebetweenthecorerefractiveindexn1andthecladdingrefractiveindexn2isdefinedAn1-n2Bn1/n2C(n1-n2)/n1D(n1-n2)/n2第4題Themeridianplaneisdefinedastheplaneintersectingwiththefiberaxisandperpendiculartothefiberwall.第5題ThefollowingthreeformsofsteprefractiveindexfibersarerankedfromlargesttosmallestrefractiveindexstepasfollowsAAll-glassfiber,PCSfibers,All-plasticfiberBAll-plasticfiber,All-glassfiber,PCSfibers,CPCSfibers,All-plasticfiber,All-glassfiber,DAll-plasticfiber,PCSfibers,All-glassfiber,第6題Theopticalfiberwithlargernumericalapertureismoresuitableforapplications.第7題Whatisthemaineffectoftheabsorptionlossofopticalfibersintheshortwavelengthregion?AInfraredabsorptionBUVabsorptionCBendingattenuationDMeltingattenuation第8題Theintrinsicabsorptionattenuationcanbereducedbyreasonablyselectingthedopingmaterialoftheopticalfiberinthemanufacturingprocess.第9題Whichofthefollowingisnonlinearscattering?ARayleighscatteringBMilescatteringCBrillouinscatteringDOpticalscattering第10題Athighpowertransmission,stimulatedRamanscatteringandstimulatedBrillouinscatteringinthefiberwon'tresultinconsiderablelosses.第11題Whichofthefollowingisnotbelongtoconnectionlossofopticalfiber?APermanentopticalfiberconnectionBEmergencyconnectionCFlexibleconnectionDMacrobendingloss第12題Macrobendingiscausedbythenon-uniformityintroducedduringtheproductionprocessofthefiber,unevenpressureduringcabling,anddifferentialthermalexpansionandcontractionofdifferentpartsofthefiberduringusage,resultinginmicron-levelbendingalongthefiber'saxis.第13題Thecorrectstatementis:ATofacilitatethetransmissionoflightwavesinthecore,therefractiveindexofthecladdingmustbeequaltotherefractiveindexofthecore.BTofacilitatethetransmissionoflightwavesinthecore,therefractiveindexofthecladdingmustbegreaterthantherefractiveindexofthecore.Cofacilitatethetransmissionoflightwavesinthecore,therefractiveindexofthecladdingmustbesmallerthantherefractiveindexofthecore.D(a)Tofacilitatethetransmissionoflightwavesinthecore,therefractiveindexofthecladdingmustbegreaterthanthatofthecoatinglayer.第14題TheprinciplebehindconfininglightwithinthecoreofanopticalfiberwithcladdingisARefractionBTotalinternalreflectionattheboundaryofthecladding.CTotalinternalreflectionattheboundarybetweenthecladdingandthecoatinglayer.DReflectionfromtheopticalfiberplasticcoatinglayer.第15題Thegradient-indexfiberutilizestheprincipleoflightscatteringtotransmitlight第16題Therefractiveindexofthegradient-indexfibercoreisgenerallyslightlysmallerthanthatofthecladding.Post-classexercise2第1題Whenthefiberhasacertainradiusofcurvature,itwillproduce____.正確答案：:Radiationloss第2題Forabsorptionloss,itinvolvestheconversionofopticalcarrierenergyintootherformsofenergy,usuallythermalenergy.第3題Radiationattenuationisoccurwhenthefiberhasacertainradiusofcurvature.第4題Theradiationattenuationofopticalfibersoccurswhenthefiberhasalargerradiusofcurvature.第5題Microbendingofopticalfibersisprimarilycausedbythebendingofthefiberalongitsaxis.第6題Macrobendingisalargescalebendinginevitablyappearsintheproduction,connectionandconstructionofopticalcable.第7題Whichbandisknownfortheabsorptionofhydroxideions(OH-)leadingtoasharpincreaseinloss,alsoknownasthewaterpeak?AO-bandBE-bandCS-bandDU-band第8題Whatdoesthe"E"inE-bandstandfor?AExtendedBEfficientCEffectiveDExponential第9題Whichbandiswidelyusedinmetropolitanareanetworks,long-distance,ultralong-distance,andsubmarineopticalcablesystems?AO-bandBE-bandCS-bandDC-band第10題Whatdoesthe"O"inO-bandstandfor?AOriginalBOptimalCOverlappingDOperational第11題Linearscatteringisdividedinto____and____.正確答案：:Rayleighscattering正確答案：:Milescattering第12題Rayleighscatteringisnotintrinsicscattering第13題Inthe1.55μmband,thelosscausedbyRayleighscatteringstillreaches0.18-0.2dB/km,whichisstillthemaincauseofthelossinthisband.第14題Transitionmetalions,includingiron,cobalt,nickel,copper,manganese,chromium,etc.,haveastrongabsorptioneffectinthewavelengthrangeusedinopticalcommunication.第15題Scatteringlossesarecategorizedintolinearscatteringlossesandnonlinearscatteringlosses.第16題Typicallyinthefabricationofopticalfibers,covalentbondsdonotbreakwhenthefibermaterialissubjectedtosomekindofthermalexcitation第17題ThelossmechanismfortheOHionisthestretchingvibration,justasfortheabsorptionbytheSiObond.第18題Whichoftheseisnotoneofthethreewindowsoffiberopticcommunications?A1.39umB1.24umC0.85umD0.95um第19題Whichisnotpartoftherangeofsidebandabsorptionpeaksproducedbytheelectronicstructureofmetallicimpurities?A0.55umB0.38umC0.99umD1.05um第20題Absorptionlossesdonotincludewhichofthefollowing?AconnectionlossBultravioletabsorptionCinfraredabsorptionDintrinsicmaterialabsorption第21題Usingopticalfibermaterialswithahigherrefractiveindexcanreduceabsorptionlosses.第22題Inopticalfibercommunication,infraredlightwithlongerwavelengthsismoreeasilyabsorbed.第23題Opticalfiberabsorptionlossesprimarilyaffectthefrequencycharacteristicsoflightsignals.第24題Metalmaterialsaretypicallyaprimarycauseofopticalfiberabsorption.第25題Opticalfiberabsorptionlossesareindependentofthewavelengthoflight.第26題Howcanabsorptionlossesinopticalfibersbeminimized?AIncreasethelengthoftheopticalfiberBChoosematerialswithahighrefractiveindexCUsematerialswithlowlossesDIncreasetheintensityoflight第27題Opticalfiberabsorptionlossesleadtoareductioninthesignal'swhichcharacteristic?AAmplitudeBFrequencyCPolarityDPhase第28題Inopticalfibers,whichwavelengthrangeoflightismorepronetobeabsorbedbyglassmaterial?AVisiblelightBInfraredlightCUltravioletlightDLaserlight第29題Inopticalfibercommunication,whichmaterialiscommonlyresponsibleforcausingopticalabsorption?AQuartzBMetalCWaterDGlass第30題Whatprimarilycausesabsorptionlossesinopticalfibers?ARefractionBScatteringCAbsorptionDReflection第31題Accordingtothedistributionofrefractiveindex,itcanbedividedinto____and____opticalfibers.正確答案：:step正確答案：:gradient第32題Thecorediameterofthesingle-modefiberis____μm.正確答案：:10第33題Inopticalfibertransmission,signaltransmissionmainlydependson____.正確答案：:totalreflection第34題Accordingtothetransmissionmodeoflightinthefiber,thefibercanbedividedintosingle-modefiberandmulti-modefiber第35題Step-indexopticalfiberisprimarilyusedfordatastorageapplications.第36題Atpresent,thelossof1550μmcommercialopticalfiberislessthan________dB/km.A0.1B0.2C0.3D0.4第37題Theoperatingwavelengthoftheshort-wavelengthfiberisA0.6～0.8μmB0.8～0.9μmC1.0～1.7μmD2μm～2.2μm第38題Ifthecorerefractiveindexofastepfiberisn1=1.5andtherelativerefractiveindexdifference△=2%,thenthenumericalapertureNAofthefiberisequaltoA3B0.3C1.5D0.02第39題Thebasicstructureofstep-indexopticalfiberincludesthe________and________.ACoreandCladdingBFibercoreandCladdingCCoreandSheathDCoreandOpticallayer第40題Therefractiveindexchangeinstep-indexopticalfibercausesthe________,makingthemfollowaspecificpath.AScatteringBReflectionCInterferenceDDiffraction第41題Theall-plasticfiberisoftenreferredtoas____.正確答案：:polymeropticalfiber第42題Thewave-particledualityoflightis:____and____.正確答案：:volatility正確答案：:corpuscularproperty第43題Therefractiveindexchangeinstep-indexopticalfibercanbeusedfordirectionalpropagationoflightsignals.第44題Step-indexopticalfiberissuitableformultimodepropagation.第45題Therefractiveindexchangeinstep-indexopticalfiberistypicallyachievedbycontrollingthechemicalcompositionofthefibermaterial.第46題Theadvantageofstep-indexopticalfiberoverconventionalopticalfiberis:ALowerbandwidthBHigherlossCGreatertransmissiondistanceDSmallerrefractiveindex第47題Inthedesignofstep-indexopticalfiber,theregionwheretherefractiveindexchangesistypicallycalled:ACoreBCladdingCFibercoreDTransitionzone第48題Step-indexopticalfiberisprimarilyusedfor:ADatastorageBHigh-speedinterconnectionCHigh-energyphysicsexperimentsDChemicalanalysis第49題Instep-indexopticalfiber,theabruptchangeinrefractiveindexresultsin:ADiffusionoflightsignalsBReflectionoflightsignalsCDiffractionoflightsignalsDNormalpropagationoflightsignals第50題Whatisthemaincharacteristicofstep-indexopticalfiber?AMultimodepropagationBUniformrefractiveindexCAbruptchangeinrefractiveindexDReflectionoflightsignals第51題Thefirstlowlossopticalfiberwasmanufacturedby____companyintheUnitedStatesin____,withalossvalueof20db/km.正確答案：:Corning正確答案：:1970第52題Opticalfiberismadeof____.正確答案：:glass第53題Inthetube,JohnTyndallfoundthatlightcanbetransmittedina____shape.正確答案：:zigzag第54題Whatkindoflightphenomenondoessignaltransmissioninopticalfiberrelyon?Itreliesonaspecialreflectionphenomenon---____..正確答案：:totalreflection第55題Lighthaswaveparticleduality.Sometimestheexternalappearanceis____,andsometimestheappearanceis____.正確答案：:granular正確答案：:volatile第56題Theopticalfiberasthinashumanhairactuallyreferstoasingleopticalfiber,whichiscomposedofcore,claddingandcoating.第57題Thetheoreticalmaximumlossofopticalfiberisdeterminedbytheintrinsicabsorptionandintrinsicscatteringofitsmaterial.第58題Until1966,______,thefatherofopticalfiber,publishedafamouspaper,inwhichheclearlystatedthatthelossofopticalfibercouldbereducedto20db/kmbyimprovingthepreparationprocessandimprovingthepurityofthematerial.ANewtonBGaoKunCJohnTyndallDDr.kapani第59題______characterizethefluctuationoflight.AReflectionandrefractionBDiffractionandinterferenceCReflectionanddiffractionDRefractionanddiffraction第60題Whatphenomenacharacterizethegranularityoflight?Itisourcommon______.AreflectionandrefractionBdiffractionandinterferenceCreflectionanddiffractionDrefractionanddiffraction第61題Thestructureofgradientrefractiveindexfiberscanbedividedintosingle-modefibersandmulti-modefibers第62題Atpresent,thelossofopticalfibersat1550nmcanreacharound0.2dB/nm,approachingthetheoreticallimitoffiberloss.第63題Therefractiveindexinthecoreofamultimodegradientrefractiveindexfiberisintermittentlytransformed.第64題Thelowlosswindowsusedinfiberopticcommunicationareinthe1310mm,850nm,and1550nmbands第65題Accordingtothedifferentrefractiveindexdistributionofthefibercross-section,commonlyusedfiberscanbedividedintostepfibers,gradientfibers,single-modefibers,andmulti-modefibers第66題Accordingtothecause