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1、附錄一、英語原文OpticalfiberAbstract:Anopticalfiber(oropticalfiber)isaflexible,transparentfibermadeofapureglass(silica)notmuchthickerthanahumanhair.Itfunctionsasawaveguide,or“l(fā)ightpipe”[1],totransmitlightbetweenthetwoendsofthefiber.[2]Thefieldofappliedscienceandenginee
2、ringconcernedwiththedesignandapplicationofopticalfibersisknownasfiberoptics.Opticalfibersarewidelyusedinfiber-opticcommunications,whichpermitstransmissionoverlongerdistancesandathigherbandwidths(datarates)thanotherformsofcommunication.Fibersareusedinsteadofmeta
3、lwiresbecausesignalstravelalongthemwithlesslossandarealsoimmunetoelectromagneticinterference.Fibersarealsousedforillumination,andarewrappedinbundlessothattheymaybeusedtocarryimages,thusallowingviewinginconfinedspaces.Specially-designedfibersareusedforavarietyof
4、otherapplications,includingsensorsandfiberlasers.Opticalfiberstypicallyincludeatransparentcoresurroundedbyatransparentcladdingmaterialwithalowerindexofrefraction.Lightiskeptinthecorebytotalinternalreflection.Thiscausesthefibertoactasawaveguide.Fibersthatsupport
5、manypropagationpathsortransversemodesarecalledmulti-modefibers(MMF),whilethosethatonlysupportasinglemodearecalledsingle-modefibers(SMF).Multi-modefibersgenerallyhaveawidercorediameter,andareusedforshort-distancecommunicationlinksandforapplicationswherehighpower
6、mustbetransmitted.Single-modefibersareusedformostcommunicationlinkslongerthan1,050meters(3,440ft).Joininglengthsofopticalfiberismorecomplexthanjoiningelectricalwireorcable.Theendsofthefibersmustbecarefullycleaved,andthensplicedtogether,eithermechanicallyorbyfus
7、ingthemwithheat.Specialopticalfiberconnectorsforremovableconnectionsarealsoavailable.【keywords】opticalFiberMulti-modefiberIndexofrefractionTotalinternalreflectionabsorptionFiberoptics,thoughusedextensivelyinthemodernworld,isafairlysimple,andrelativelyold,techno
8、logy.Guidingoflightbyrefraction,theprinciplethatmakesfiberopticspossible,wasfirstdemonstratedbyDanielColladonandJacquesBabinetinParisintheearly1840s.JohnTyndallincludedademo