Ifayibha yemodi eyodwa (SingleModeFiber) iyifayibha yokubona engadlulisa imodi eyodwa kuphela ngobude obucacisiwe. Umongo wengilazi ophakathi mncane kakhulu (ububanzi bomnyombo ngokuvamile bungu-9 noma 10μm).
Ngakho-ke, ukuhlakazeka kwayo kwe-inter-mode kuncane kakhulu, kulungele ukuxhumana okukude Nokho, kukhona futhi ukuhlakazeka kwezinto ezibonakalayo kanye nokuhlakazeka kwe-waveguide, ukuze i-fiber yemodi eyodwa inezidingo eziphakeme kububanzi be-spectral nokuzinza komthombo wokukhanya, okungukuthi, ububanzi be-spectral kufanele bube buncane futhi ukuzinza kube ngcono.
Kamuva, kwatholakala ukuthi ku-1.31μm wavelength, ukuhlakazwa kwezinto ezibonakalayo kwe-fiber optical yemodi eyodwa kanye nokuhlakazeka kwe-waveguide kukuhle futhi kubi, futhi ubukhulu bufana ncamashi. Ngale ndlela, isifunda se-wavelength esingu-1.31μm sesiphenduke iwindi elikahle lokusebenza lezokuxhumana nge-fiber optical, futhi manje isiyibhande eliyinhloko elisebenzayo lezinhlelo zokuxhumana ezisebenzayo ze-fiber optical. Imingcele eyinhloko ye-1.31μm evamile ye-fiber yemodi eyodwa inconywa yi-International Telecommunication Union ITU-T ku-G652 Certain, ngakho le fiber ibizwa nangokuthi i-G652 fiber. I-fiber yemodi eyodwa ingahlukaniswa ibe i-fiber yemodi eyodwa engu-652, i-fiber yemodi eyodwa engu-653 kanye ne-fiber yemodi eyodwa engu-655.
Incazelo "ye-fiber yemodi eyodwa" ezincwadini zezemfundo: ngokuvamile, lapho i-v ingaphansi kuka-2.405, i-fiber eyodwa kuphela edlulayo, ngakho ibizwa ngokuthi i-fiber yemodi eyodwa. Umongo wayo mncane kakhulu, cishe ama-microns angu-8-10, futhi ukuhlakazeka kwemodi Kuncane kakhulu. Isici esiyinhloko esithinta ububanzi bebhande lokudlulisa i-fiber ukuhlakazeka okuhlukahlukene, futhi ukuhlakazeka kwemodi kubaluleke kakhulu. Ukuhlakazwa kwefayibha yemodi eyodwa kuncane, ngakho-ke kungadlulisa ukukhanya kubhendi yefrikhwensi ebanzi ibanga elide.
Ifayibha yemodi eyodwa inobubanzi obuyingqikithi obuyi-10 micron, evumela ukudluliswa kwe-beam yemodi eyodwa, enganciphisa umkhawulokudonsa kanye ne-Modal Dispersion. Kodwa-ke, ngenxa yokuthi ububanzi be-fiber core yemodi eyodwa buncane kakhulu, kunzima ukulawula ukudluliswa kwe-beam, ngakho-ke kuyadingeka ukuthi ama-laser abizayo asetshenziswe njengomthombo wokukhanya, futhi umkhawulo oyinhloko wezintambo ezibonakalayo zemodi eyodwa ukuhlakazeka kwezinto ezibonakalayo. . Izintambo ezibonakalayo zemodi eyodwa ikakhulukazi zisebenzisa amalaser ukuthola umkhawulokudonsa wefrikhwensi ephezulu. Njengoba ama-LED azokhipha inombolo enkulu yemithombo yokukhanya enomkhawulokudonsa ohlukile, izidingo zokuhlakazeka kwezinto zibaluleke kakhulu. Ifayibha yemodi eyodwa ingasekela ibanga elide lokudlulisela kunefayibha yemodi eminingi. Kunethiwekhi engu-100Mbps Ethernet noma ye-1G Gigabit, i-fiber yemodi eyodwa ingasekela ibanga lokudlulisela elingaphezu kuka-5000m ngokombono wezindleko. Ngokombono wezindleko, njengoba i-transceiver optical ibiza kakhulu, izindleko zokusebenzisa i-fiber optical yemodi eyodwa zizoba phezulu kunezindleko ze-multi-mode optical fiber cable.
Ukusatshalaliswa kwenkomba ye-refractive kufana ne-fiber optical abrupt, ubukhulu be-core buyi-8 ~ 10μm kuphela, futhi ukukhanya kusakazeka ngendlela yomugqa eduze kwe-eksisi eyinhloko. Ngenxa yokuthi le fibre ingadlulisela imodi eyodwa kuphela (izimo ezimbili ze-polarization ziwohlokile), ibizwa ngokuthi i-fiber yemodi eyodwa futhi ukuhlanekezela kwayo kwesignali kuncane kakhulu.