Kukho iindidi ezine eziphambili zokulungiswa kombono—i-emmetropia, i-myopia, i-hyperopia, kunye ne-astigmatism.
I-Emmetropia kukubona okugqibeleleyo. Iliso sele libuyisela ukukhanya kwi-retina kwaye alidingi ukulungiswa kweeglasi.
I-Myopia yaziwa kakhulu ngokuba kukubona okukufutshane. Yenzeka xa iliso lilide kakhulu, nto leyo ebangela ukuba ukukhanya kugxile phambi kwe-retina.
Ukuze kulungiswe i-myopia, ugqirha wakho wamehlo uya kukunika iilensi ze-minus (-X.XX). Ezi lensi ze-minus zityhala indawo yokugxila ngasemva ukuze ihambelane ngokuchanekileyo ne-retina.
I-Myopia yeyona ndlela ixhaphakileyo yokuphoswa kwengxaki kuluntu lwanamhlanje. Enyanisweni, kucingelwa ukuba yingxaki yehlabathi, njengoko uninzi lwabantu lufunyaniswa lunale ngxaki minyaka le.
Aba bantu banokubona kakuhle kufutshane, kodwa izinto ezikude zibonakala zingacacanga.
Kubantwana, ungabona umntwana enengxaki yokufunda ibhodi esikolweni, ephethe izinto zokufunda (iiselfowuni, iincwadi, ii-iPad, njl.njl.) kufutshane kakhulu nobuso bakhe, ehleli kufutshane kakhulu neTV kuba “engaboni”, okanye ekrwempa amehlo akhe kakhulu okanye ewahlikihla.
Kwelinye icala, i-hyperopia yenzeka xa umntu ekwazi ukubona kude kakhulu, kodwa angabi nangxaki yokubona izinto kufutshane.
Ezinye zezona zikhalazo zixhaphakileyo nge-hyperopes asikuko ukuba aziboni, kodwa endaweni yoko ziba neentloko ezibuhlungu emva kokufunda okanye ukwenza umsebenzi wekhompyutha, okanye ukuba amehlo azo ahlala ediniwe okanye ediniwe.
I-Hyperopia yenzeka xa iliso lifutshane kakhulu. Ngenxa yoko, ukukhanya kugxile kancinci ngasemva kwe-retina.
Xa ubona izinto ngendlela eqhelekileyo, umfanekiso ujoliswa ngqo kumphezulu we-retina. Kwi-hyperopia, i-cornea yakho ayikhanyisi kakuhle ukukhanya, ngoko ke indawo yokugxila isemva kwe-retina. Oku kwenza izinto ezikufutshane zibonakale zingacacanga.
Ukulungisa i-hyperopia, oogqirha bamehlo banika iilensi ze-plus (+X.XX) ukuze indawo yokugxila ifike ngokuchanekileyo kwi-retina.
I-Astigmatism yenye into eyahlukileyo. I-Astigmatism yenzeka xa umphezulu ongaphambili weliso (i-cornea) ungqukuva ngokugqibeleleyo.
Cinga nge-cornea eqhelekileyo efana nebhola yomnyazi enqunyulwe phakathi. Igqibelele kwaye ilingana kuzo zonke iindlela.
I-cornea e-astigmatic ifana neqanda elibilisiweyo elisikwe phakathi. Elinye i-meridian lide kunelinye.
Ukuba neemeridians ezimbini ezahlukeneyo zeliso kubangela ukuba kubekho iindawo ezimbini ezahlukeneyo zokugxila. Ke ngoko, kufuneka kwenziwe ilensi yeglasi ukuze ilungele zombini iimeridians. Le mithi iya kuba namanani amabini. Umzekelo-1.00 -0.50 X 180.
Inani lokuqala libonisa amandla afunekayo ukulungisa i-meridian enye ngelixa inani lesibini libonisa amandla afunekayo ukulungisa enye i-meridian. Inani lesithathu (X 180) lichaza nje apho ii-meridian ezimbini zilele khona (zinokuqala ukusuka ku-0 ukuya kwi-180).
Amehlo afana neminwe—akukho zimbini zifana nqwa. Sifuna ubone okona kulungileyo kuwe, ngoko ke ngeentlobo ngeentlobo zeemveliso zeelensi singasebenzisana ukufumana isisombululo esifanelekileyo sokuhlangabezana neemfuno zakho.
Indalo yonke inokubonelela ngeelensi ezingcono zokulungisa iingxaki zamehlo ezingentla. Nceda ugxile kwiimveliso zethu:www.universeoptical.com/products/