Úvod
Anopticaldevicethatrealizesthedistributionorcombinationofopticalsignalpoweramongdifferentopticalfibers.Itisconstitutedbythemutualexchangeofguidedwaveenergyindifferentfiberfacesadjacenttothefibercorearea.Accordingtothetypeoffiberused,itcanbedividedintomultimodefiber,singlemodefiberandpolarizationmaintainingfibercoupler.
Optická spojka (spojka), také známá jako rozdělovač (rozdělovač), konektor, adaptér, příruba, se používá k realizaci dělení/kombinování optických signálů,
modul Optická spojka (3 fotografie)
Orcomponentsusedtoextendopticalfiberlinks,belongtothefieldofopticalpassivecomponents,andareusedintelecommunicationsnetworks,cableTVnetworks,userloopsystems,andlocalareanetworks.Willbeappliedto.Opticalfibercouplerscanbedividedintostandardcouplers(belongingtowaveguidetype,doublebranch,unit1×2,thatis,theopticalsignalisdividedintotwopowers),direct-connectcoupler(connectingtwoopticalfibersofthesameordifferenttypesofopticalfiberinterfaces,withExtendtheopticalfiberlink),star/treecoupler,andwavelengthmultiplexer(WDM,ifthewavelengthishigh-densityseparation,thatis,thewavelengthspacingisnarrow,itbelongstoDWDM),theproductionmethodsincludesintering(Fuse),microTherearethreetypes:MicroOpticsandWaveGuide.Thesinteredmethodaccountsforthemajority(about90%).Themanufacturingmethodofsinteringmethodistomeltandstretchtwoopticalfiberstogethertopolymerizethecorestogethertoachieveopticalcoupling.Themostimportantproductionequipmentistheopticalfiberfusionsplicer,whichisalsoanimportantstep.Someimportantstepscanbemanufacturedbymachines,butaftersintering,peoplestillneedtoworktoinspectandpackage,solaborcostsabout10-15%,andtheuseofmanualinspectionandpackagingmustensuretheconsistencyofquality,whichisalsothereasonformassproduction.Itmustbeovercome,butthetechnicaldifficultyisnotashighasthatofDWDMmodulesandopticalactivecomponents.Therefore,mostofthemanufacturerswhowanttoentertheopticalfiberindustryattheinitialstagewillstartwithopticalcouplers,andthegrossprofitwillbe20-30%.
Zásada
Theopticalfibercouplerisadetachable(movable)connectiondevicebetweentheopticalfiberandtheopticalfiber.ItpreciselyconnectsthetwoendfacesoftheopticalfibertomakethelaunchingfiberTheoutputlightenergycanbecoupledtothereceivingfibertothemaximumextent,anditcaninterveneintheopticallinktominimizetheimpactonthesystem.Forthewaveguidefibercoupler,itisgenerallyaY-branchelement,andtheopticalsignalinputbyanopticalfibercanbedividedequallybyit.Whentheopeningangleofthebranchofthecouplerincreases,theamountoflightleakingintothecladdingwillincreasetoincreasetheexcessloss.Therefore,theopeningangleisgenerallywithin30°,sothelengthofthewaveguidefibercouplercannotbetooshort.
Jednovláknová spojka
Jednovláknová spojkaisthemostwidelyused.The2×2single-modefibercoupleristypical,anditscompositionisshowninthefigure.Ithastwoinputterminalsandtwooutput
terminals,withacouplingareainthemiddle.Figure2(a)ismadebythemelt-stretchingprocess.Thestretchedpartformsataperedcouplingzone.Stretchingmakesthelightenergyofthecoreareaexpandoutofthecore;atthesametime,bringingthetwocoresclosetoeachother,bothofwhichenhancethecoupling.Theopticalsignalinputby1or2isdistributedthroughthetaperedcouplingareaandoutputbythe3and4terminals.Thedistributionratioiscalledthecouplingratio,whichiscontrolledbythelengthofthestretchingzone.Inthefigure(b),partofthecladdingisremovedfromtheopticalfiberembeddedinthequartzblockwithacertaincurvaturebythegrindingandpolishingmethod,andthentwosuchquartzblocksarepressedtightlytomakethetwocoresclosetoeachothertoformanopticalfibercoupler.Thecouplingratioisdeterminedbytheproximityofthecoreandtheradiusofcurvatureofthefiberinthequartzblock.Thecouplingratiocanbeselectedfrom1%to99%,andtheinsertionlossislessthan0.5dB.Theopticalsignalcoupledoutoftheinputlightintheoppositedirectionisextremelyweak,sothefibercouplerisoftencalledadirectionalcoupler.
Multimodevláknová spojka
Theprincipleandstructureofthemultimodefibercouplerarebasicallysimilartotheabove,exceptthatthegrindingandpolishingdevicerequiresstrongcoupling,sothegrindingandpolishingplaneentersthefiber.core.Onthebasisofthepolished2×2fibercoupler,anadjustablecouplercanalsobemade.Inthecaseofacertainwavelength,thecouplingratiochangeswiththeangleformedbythetwopolishedfibers,sothecouplingratiocanbechangedbyadjustingtherelativedirectionofthetwofibers.
Inopticallocalnetworksorotheroccasions,l×N,N×1couplersorN×Mcouplers(orstarcouplers)arealsoused.Thefirstnumberrepresentsthenumberofinputterminals,andthefirstThetwonumbersrepresentthenumberofoutputterminals.Thesecouplersaremadebyfusiondrawingmethod.
Klasifikace
Accordingtothedifferentopticalfibercoupling,therearethefollowingclassifications:
SCopticalfibercoupler:appliedtoSCopticalfiberinterface,itcanbeseenwithRJ-45interfaceItlooksverysimilar,buttheSCinterfaceisflatter.Theobviousdifferenceisthecontactsinside.Ifitis8thincoppercontacts,itisanRJ-45interface.Ifitisacopperpillar,itisanSCfiberinterface.
LCoptická spojka: Používá se v LC rozhraní s optickým vláknem pro připojení konektoru modulu SFP. Je vyrobena ze snadno ovladatelného západkového mechanismu modulárního konektoru (RJ). (Běžně používané ve směrovačích)
FCopticalfibercoupler:usedinFCopticalfiberinterface,theexternalstrengtheningmethodisametalsleeve,andthefasteningmethodisaturnbuckle.GenerallyusedontheODFside(mostusedonthedistributionframe)
STfibercoupler:usedinSTfiberinterface,oftenusedinfiberdistributionframes,theshellisround,andthefasteningmethodisturnbuckles.(For10Base-Fconnection,theconnectorisusuallySTtype.Oftenusedinopticalfiberdistributionframe)