Mekhoa e mene ea deposition e hlahisa hoo e batlang e le silika e 'ngoe le e' ngoe lefatšeng: MCVD, PCVD, OVD le VAD. Ha se mefuta e mene e hlodisanang ya ntho e le nngwe. E 'ngoe le e 'ngoe e lula sebakeng se fapaneng ka nepo, tlhahiso le litšenyehelo, kahoo mokhoa o ka morao ho preform ea hau o etsa qeto ka khutso hore na o ka hula mefuta efe ea fiber le hore na khalase ea hau e bitsa bokae ka k'hilomithara. Tataiso ena e bapisa tse nne, ebe o u fa matrix a liqeto le lethathamo la tlhahlobo ea bafani ba thepa. Bala halofo ea pele bakeng sa lintlha tsa motheo, halofo ea bobeli haeba u totobatsa kapa u batla.
Pele ho li-acronyms tse 'nè: tlhahiso ea preform ke mesebetsi e 'meli, eseng a le mong
Lipuisano tse ngata tsa ho batla li ea ka thoko mona. Moreki oa botsa “ke VAD kapa OVD ea hau ea pele?” mme a fumana karabo e utlwahalang e hlakile empa e sa hlalose letho, hobane preform ea sejoale-joale e hahiloe ka mekhahlelo e 'meli e fapaneng eo hangata e sebelisang mekhoa e' meli e fapaneng.
Mohato 1 - molamu oa mantlha. Sekhechana sena se na le fiber core hammoho le karolo ea lesela le ka hare, 'me e beha lintlha tsa hau tsa optical: attenuation, phasalatso, cutoff wavelength, profil ea index ea refractive. VAD le OVD li laola lithupa tsa mantlha tsa singlemode. PCVD e na le lifaele tse rarahaneng tsa multimode.
Mohato 2 - ho koaheloa ho feteletseng. Baetsi ba haha
Kahoo “re sebelisa VAD” ke halofo feela ea karabo. U hloka likarolo tse peli pele u ka bapisa mantsoe a qotsitsoeng a mabeli, 'me halofo ea overcladding ke moo barekisi ba fapaneng haholo. Ea rona karohano ea seo preform e hlileng e leng sona covers the structure in more depth if you want the fundamentals first.
Fiber optic preform manufacturing methods at a glance
| MCVD | PCVD | OVD | ENG | |
| Deposition location | Inside tube | Inside tube | Outside, radial | Outside, axial |
| Heat / energy source | Oxy-hydrogen flame | Microwave plasma, ~1000°C | Flame hydrolysis | Flame hydrolysis |
| Tšimoloho | Bell Labs, 1974 | Philips, 1975 | Corning, 1970 | NTT, 1977 |
| RI profile control | Precise | Highest — thousands of layers | Good | Hardest to fine-tune |
| Deposition rate | Very low | Moderate, improving | Phahameng | Phahameng, supports continuous growth |
| Max preform size | Limited by tube | Limited by tube | Very large | E kholo haholo |
| Sekoti se bohareng | E putlahile | E putlahile | Thehile, yaba ho koaloa | Haho ka moralo |
| Theko ka k'hilomithara ea fiber | Phahameng ka ho fetisisa | Bohareng ho isa hodimo | Boemo bo tlase | Boemo bo tlase |
| Molemo ka ho fetisisa ho lekana | Tse khethehileng: EDFA, PM, thata-thata | OM3/OM4/OM5, profiles tse khethehileng | Li-cores tsa Singlemode + overcladding | Singlemode e tloaelehileng le e tlase haholo ea tahlehelo |
| Sebaka se fokolang | Ha ho molumo, ha ho li-preforms tse kholo | Ha e khone ho lumellana le litšenyehelo tsa VAD/OVD ho G.652 | Tlhōrō ea histori ea metsi, joale e rarollotsoe | Liprofaele tse rarahaneng |
Bala tafole e le mokhoa oa khoebo, eseng boemo. Mekhoa ea ka hare ea li-tube e reka ho nepahala ha profil 'me e lefa chelete e ngata. Mekhoa ea kantle ea li-tube e reka sekala le ho lefa ka mokhoa o feto-fetohang oa profil.
1. MCVD: molemo ka ho fetisisa bakeng sa ho nepahala, eseng kamehla molumo
Bell Labs e hahiloeng MCVD ka 1974. Lelakabe la oxy-hydrogen le chesa bokantle ba silika e hloekileng haholo ha likhase tse reactant li oxidize ka hare ho eona., lera ka lera. Hang ha deposition e felile, mocheso o phahameng o etsa hore tube e be molamu o tiileng oa mantlha.
Thepa e bonolo mme taolo ea index ea refractive e ntle e le kannete. Meeli e 'meli e boima e ile ea felisa mosebetsi oa eona oa telecom: sekgahla sa deposition se tlase haholo, le boholo ba 'mele oa silica tube caps hore na u ka haha
Tšoara MCVD e le ea khale bakeng sa tlhahiso ea molumo oa G.652. Ea pholoha, mme e atleha, ka khalase e khethehileng - fiber ea erbium-doped bakeng sa li-amplifiers, polarization-ho boloka fiber, fiber e hanyetsanang le mahlaseli bakeng sa mosebetsi oa nyutlelie le oa sebaka. Haeba mofani oa thepa a u fa mofuta oa singlemode o tloaelehileng o thehiloeng ho MCVD ka theko ea tlholisano, botsa joang, hobane mokhoa oa moruo ha o o tšehetse.
U lokela ho hlakisa MCVD neng: o hloka profil e tloahelehileng ka bongata mme theko ea k'hilomithara ke ea bobeli ho feta ho fumana khalase e nepahetseng eo u e kopileng..
2. PCVD: li-multimode tse phahameng le li-profile tse khethehileng
Philips e hlahisitse PCVD ho 1975, le tsa China YOFC jwale o etella lefatshe ho lona. Deposition e ntse e etsahala ka har'a tube ea silica, empa li-microwave li hlahisa plasma ho e-na le lelakabe le futhumatsang lebota ho tsoa ka ntle. Khalase e beha ka kotloloho ho hoo e ka bang 1000°C - tlase, ha mekhoa ena e tsamaea.
Precision ke khang eohle ea PCVD. Mokhoa ona o beha likete tsa lilae tse tšesaane, e fang baenjiniere taelo ea boemo ba micron ea profil ea refractive index. Seo se bohlokoa haholo bakeng sa fiber ea graded-index multimode, moo bandwidth e itšetlehileng ka hore na profil ea parabolic e hlahisoa ka botšepehi joang. OM3, OM4 le OM5 ke sebaka sa lehae sa PCVD.
Mehloli ea matla a microwave e matla e phahamisitse litheko tsa ho beoa ha PCVD haholo. E ntse e lahleheloa ke VAD le OVD ka litšenyehelo tse tloaelehileng tsa singlemode, 'me ha ho na palo ea ts'ebetso ea tokiso e fetola seo.
O lokela ho hlakisa PCVD neng: o taka multimode ea graded-index kapa profaele e ikhethang moo bandwidth le profil fidelity, eseng litšenyehelo tsa khalase, etsa qeto ea hore na fiber ea feta.
3. OVD: ke hobane'ng ha tekanyo le overcladding taba
Corning o ile a qapa OVD ka 1970, 'me e ntse e le mokhoa oa maiketsetso o sebelisoang ka ho fetisisa lefatšeng. SiCl₄ le likhase tsa dopant li itšoara ka lelakabe la oxy-hydrogen, 'me phofshoana ea silika e hlahisoang e beha radially holim'a molamu o potolohang oa sepheo.
Seo u se fumanang pele ke sekoti sa soot boule, eseng khalase. Basebelisi ba ntša molamu o shebiloeng, ebe o ntša metsi 'me u sinter boule sebakeng sa chlorine se nang le mocheso o phahameng. Mohato oo o koala sekoti se bohareng ebe o ntša metsi, ho siea molamu o tiileng o bonaletsang.
Ho kokota pele ho OVD e ne e le ho fokotsa tlhoro ea metsi ka 1383nm, qalisoa ho lesoba la bohareng. Indasteri e ile ea e rarolla - mohala oa Corning oa SMF-28e o ile oa rarolla khang lilemong tse fetileng. Haeba mohlolisani a ntse a qotsa tlhoro ea metsi e bohareng e le lebaka la ho qoba OVD, ba qotsa lingoliloeng tsa bo-1990.
Boemo ba 'nete ba OVD kajeno bo habeli. E etsa lithupa tsa mantlha tsa singlemode, 'me ke eona theknoloji e hlahelletseng ka ho fetesisa lefatšeng ka bophara, hobane sekhahla se phahameng sa deposition hammoho le preforms tse kholo haholo hammoho le litšenyehelo tse tlase ke sona seo mohato oa overcladding o se hlokang. Limela tse etelletseng pele le tsona li fetotse SiCl₄ bakeng sa li-siloxane tse se nang chlorine joalo ka OMCTS. (D4) sethaleng sa overcladding, ho fokotsa litšenyehelo le mojaro oa tikoloho.
O lokela ho hlakisa OVD neng: o batla tsela e theko e tlase haholo ho li-preforms tse kholo tse tloaelehileng tsa singlemode, kapa u ntse u lekola hore na ke mang ea etsang overcladding ea hau - moo OVD e leng karabo ea kamehla sekala.
4. ENG: tlhahiso e kgolo le ho thetheha tlase
Japane NTT e ntlafalitse VAD ka 1977. E boetse e sebetsa ho flame hydrolysis, empa geometry e fapana ka tsela ea bohlokoa: soot boule e hola ka ho hlaka ho bapa le mokoloko oa ona, ho tloha tlase holimo, ho se na molamu o amehang.
VAD ea sejoale-joale e arola ho beoa le ho kopanya mochini ka metjhini e 'meli - beha sekoti sa porous, ebe o e fetisetsa sebōping se inehetseng bakeng sa ho felloa ke metsi 'meleng le ho sintering.
Ha ho na molamu oa sepheo o bolelang hore ha ho na lesoba le bohareng ho koala. Bohloeki ba ka hare bo tsoa holimo haholo, ke ka lebaka leo VAD e leng mokhoa oa khetho bakeng sa fiber e tlaase-tlaase. Khōlo ea Axial e boetse e iketsetsa tlhahiso e tsoelang pele ho e-na le li-batch cycles. ZTT, Hengtong le Futong li tsamaisa VAD bakeng sa bongata bo bongata ba lithupa tsa tsona tsa mantlha tsa singlemode.
Ho tšoasa ke taolo ea profil. Ho thata ho theha profil e rarahaneng ea index ea axially, kahoo VAD ha e tšoanelehe hantle bakeng sa multimode ea graded-index.
U lokela ho hlakisa VAD neng: o hlahisa singlemode e tloaelehileng kapa ea tahlehelo e tlase haholo ka molumo mme o batla khalase e hloekileng ea mantlha ka theko ea yuniti..
Matrix ea liqeto: parameter × kopo × mofuta oa moreki
| Boemo ba hau | Mokhoa oa "core rod". | Overcladding | Ke eng e hlileng e laolang qeto ea hau |
| Mokhoa o le mong oa G.652.D o tloaelehileng, bophahamo ba modumo | VAD kapa OVD | OVD (kapa RIC, sheba ka tlase) | Litšenyehelo ka k'hilomithara le lihlahisoa ho latela preform |
| Tahlehelo e tlase haholo / tsela e telele, G.654.E | ENG | OVD | Bohloeki ba mantlha, OH taolo, moeli oa attenuation |
| OM3 / OM4 / Mefuta e mengata ea OM5 | PCVD | OVD kapa RIC | RI profile botšepehi, sekhahla sa phallo ea bandwidth |
| Tse khethehileng: EDFA, PM, thata-thata | MCVD | Ts'ebeliso e khethehileng | Dopant control, ho feto-fetoha ha maemo a manyane |
| Semela se secha, boemo bo itekanetseng bo reriloeng | VAD kapa PCVD | RIC e molaong mona | Capex ka mola, ho tsitsisa ha geometri, nako ea ho qala fiber |
| Morekisi / mohoebi ea tšoanelehang mohloli | Botsa, u se ke ua nahana | Botsa ka ho toba | Ho batch-to-batch ho lumellana, lintlha tsa tlhahlobo tse ngotsoeng |
Tsela e le 'ngoe ea ho tsamaea: mokhoa oa core rod o latela mofuta oa hau oa fiber; mokhoa oa overcladding o latela sebopeho sa hau sa litšenyehelo le sekala sa semela. Bareki ba kopanyang tse peli ba qetella ba bapisa mantsoe a qotsitsoeng ao ho seng mohla a kileng a bapisoa.
Ho tloha preform ho ea fiber: ke hobane'ng ha khetho ea mokhoa e kopanya tlaase
A preform ha se sehlahisoa. Ke kenyelletso ea tora ea ho hula, 'me tora e holisa qeto e' ngoe le e 'ngoe eo u e entseng holimo.
Preform e le 'ngoe e kholo e hlahisa lik'hilomithara tse likete tsa fiber e tsoelang pele, kahoo bolelele bo bolelele bo ka huloang yuniti ka 'ngoe bo bolela liphetoho tse fokolang, nako e fokolang ea tora, le tšebeliso e betere ea thepa ea hau e turang haholo. Phoso ea jiometri ha e lekane - fiber e huleloang e na le karo-karolelano e nepahetseng ea li-core-to-cladding le profil ea refractive index ea preform., e fokotsehile ho fihla ho 125µm. Phoso ea Concentricity eo u e amohetseng ho preform e fihla e ntse e le teng k'hilomithara e 'ngoe le e 'ngoe eo u e takang, 'me u tla boela u kopane le eona e le tahlehelo ea maqeba tšimong.
Ea rona tataiso ea tlhahiso ea ho qetela ho tsamaya ka ketane e felletseng ho tloha ho diketapele tse tala ka ho taka, ho roala le ho etsa liteko haeba u hloka setšoantšo se tlase.
Ho e tlisa mmoho
Bapisa mokhoa oa core rod le fiber eo u ikemiselitseng ho e rekisa:
- VAD kapa OVD bakeng sa mokhoa o tloaelehileng o le mong,
- VAD bakeng sa tahlehelo e tlase haholo,
- PCVD bakeng sa multimode ea li-graded-index,
- MCVD bakeng sa khalase e khethehileng ea doped.
Khetha tsela e fetang tekano mabapi le sebopeho sa litšenyehelo le sekala sa semela ho fapana le hore na ke mokhoa ofe o utloahalang o le teng haholo. Ebe u netefatsa ka data e lekantsoeng - attenuation, Oh tlhoro, concentricity, mamello ea profil - hobane linomoro tseo, eseng khutsufatso, u bolelle seo u se rekang.
Fibconet e fana ka li-preform tsa optical fiber haufi le litora tsa ho hula bakeng sa bahlahisi le moaho o mocha oa batseteli ba limela kapa ho holisa mohala oa fiber.. Haeba ke boemo ba hau, hlahloba rona Phepelo ea Fektheri ea Lisebelisoa tsa Fiber Preform leqephe bakeng sa lintlha tsa ts'ebetso le litlhaloso.
