Uma ungena esitolo sezibuko bese uzama ukuthenga ipheya yezibuko, unezinhlobo ezimbalwa zamalensi ongakhetha kuye ngencwadi kadokotela. Kodwa abantu abaningi badidwa amagama athi umbono owodwa, i-bifocal kanye nenqubekela phambili. Lawa magama abhekisela endleleni amalensi ezingilazini zakho aklanywe ngayo. Kodwa uma ungenaso isiqiniseko sokuthi hlobo luni lwezibuko oludingwa incwadi yakho kadokotela, nansi ukubuka konke okusheshayo ukukusiza ukuthi uqalise.
1. Ayini Amalensi Ombono Owodwa?
Ilensi yombono owodwa empeleni iyilensi ephethe incwadi kadokotela eyodwa. Lolu hlobo lwamalensi lusetshenziselwa imiyalelo yabantu ababona eduze, ababona kude, abane-astigmatism, noma abanenhlanganisela yamaphutha e-refractive. Ezimweni eziningi, izibuko zombono owodwa zisetshenziswa abantu abadinga inani elifanayo lamandla ukuze babone kude futhi bavale. Nokho, kukhona izibuko zombono owodwa ezibekelwe injongo ethile. Isibonelo, ipheya yezibuko zokufunda ezisetshenziselwa ukufunda kuphela iqukethe ilensi yokubona eyodwa.
I-single vision lens ilungele izingane eziningi kanye nabantu abadala abancane ngoba ngokuvamile akudingeki ukuthi balungise ukulungisa kwabo ukubona ngokusekelwe ebangeni labo. Umuthi wakho wezingilazi zombono owodwa uhlale uhlanganisa ingxenye eyindilinga njengenombolo yokuqala kuncwadi yakho kadokotela futhi ingase ihlanganise nengxenye yesilinda ukuze kulungiswe i-astigmatism.
2. Ayini Amalensi E-Bifocal?
Amalensi e-Bifocal anezindawo ezimbili ezihlukene zokulungiswa kombono. Izindawo zihlukaniswa ngomugqa ohlukile ohlala uvundlile unqamule ilensi. Ingxenye engaphezulu yelensi isetshenziselwa ibanga, kanti ingxenye engezansi isetshenziselwa ukubona eduze. Ingxenye yelensi enikelwe ekuboneni eduze ingabunjwa ngezindlela ezimbalwa ezihlukene: Ingxenye engu-D, ingxenye eyindilinga (ebonakalayo/engabonakali), ingxenye yejika kanye ne-E-line.
Amalensi e-Bifocal ngokuvamile asetshenziswa uma othile engumuntu oyivelakancane ongakwazi ukuzivumelanisa namalensi aqhubekayo noma ezinganeni ezincane ezinamehlo awela lapho zifunda. Isizathu sokuthi zingasasetshenziswa kakhulu ukuthi kunenkinga evamile ebangelwa ama-bifocal lens abizwa ngokuthi “image jump”, lapho izithombe zibonakala zigxuma njengoba amehlo akho enyakaza phakathi kwezingxenye ezimbili zelensi.
3. Ayini Amalensi Aqhubekayo?
Idizayini yamalensi aqhubekayo yintsha futhi ithuthuke kakhulu kunama-bifocal. Lawa ma-lens ahlinzeka ngegradient eqhubekayo yamandla ukusuka phezulu kwelensi ukuya phansi, ehlinzeka ngoshintsho olungenamthungo lwezidingo zokubona ezahlukene. Amalensi engilazi yamehlo aqhubekayo abizwa nangokuthi i-no-line bifocal ngenxa yokuthi awanawo umugqa obonakalayo phakathi kwamasegimenti, okuwenza athandeke kakhulu ngobuhle.
Ngaphezu kwalokho, izibuko zamehlo eziqhubekayo futhi zenza kube lula ukushintsha phakathi kwebanga, elimaphakathi, kanye nezingxenye eziseduze zencwadi yakho kadokotela. Ingxenye emaphakathi yelensi ilungele imisebenzi yebanga elimaphakathi njengomsebenzi wekhompyutha. Izibuko zamehlo eziqhubekayo zinenketho yomklamo wephaseji omude noma omfushane. Iphaseji iyingxenye yelensi ekunikeza amandla okubona amabanga aphakathi nendawo.
Ngamafuphi, umbono owodwa (SV), i-bifocal, namalensi aqhubekayo ngalinye linikeza izixazululo ezihlukile zokulungisa umbono. Amalensi okubona okukodwa alungele ibanga elilodwa (eduze noma kude), kuyilapho amalensi e-bifocal naqhubekayo ekhuluma kokubili okuseduze nakude ngelensi eyodwa. Ama-Bifocals anomugqa obonakalayo ohlukanisa izingxenye eziseduze nebanga, kuyilapho amalensi aqhubekayo enikeza uguquko olungenamthungo, oluneziqu phakathi kwamabanga ngaphandle komugqa obonakalayo. Uma udinga olunye ulwazi, sicela ukhululeke ukuxhumana nathi.