Kwiimeko ezininzi zokukhubazeka okubonakalayo, i-myopia (i-closesightedness) okanye i-hypermetropia (ukujonga phambili) ibonwa. Ukutyunjwa kweziglasi phantsi kweempazamo ezinjalo kuhloswe ukuzinqanda ngokuncedisa ukusabalalisa okanye ukuqokelela iiglasi.
Indlela yokumisela i-diopter xa ukhetha izibuko?
Xa kukhethwe iiglasi isigulane sisekude kumitha engama-6 ukusuka kuyo yonke itafile ekhethekileyo. Iso ngalinye lihlolwe ngokwahlukileyo. Ukususela phezulu, isiguli sifunda iileta zomgca ngamnye. Umgca wokugqibela ufundwa ubonisa ubuninzi obubonakalayo. Emva koko, obuthathaka (ukugxilwa kwexesha elide), kwaye emva koko unamandla (i-short-focused focus) iiglasi ezigqithisiweyo zisetyenziswe kwiso. Isigulane sifunda umgca wokugqibela kwakhona, into ayibonayo. Isilawuli esinamandla kunesibonakaliso sibonisa izinga lokujonga.
Ukuba umbono uhlahloka kwi-glass convex, ngoko umlinganiselo we-myopia ebonakalayo uhlolwe. Oku kwenziwa nguncedo lweglasi ye-concave. Ukuba i-glass concave ayinakuncediswa, imbangela yokonakaliswa kwezinto ezibonakalayo zicaciswa ngokungekho.
Iindidi zeglasi kunye ne-diopters
Iindidi ezahlukeneyo zeglasi kunye ne-diopters-iiglasi-i-chameleons (photochromic). Basebenzisa i-lensch photoicromic, ezitshintsha umbala, mnyama, ngesenzo se-ultraviolet rays. Qaphela ukuba emagumbini aqingqiweyo ama-chameleons awamnyama, kuba ingilazi ye-silicate ayivumeli ukudlula kwe-ultraviolet.
Iiglasi ezifanelekileyo zeglasi zikhanya ngemizuzu engama-3, zimnyama ngomzuzu omnye. Kule meko, iilensi kufuneka zitshintshe umbala ngexesha elifanayo.
Izikhuselo ezikhuselekileyo nazo zingaba ne-diopters. Zisetyenziselwa kwimidlalo embi, ukuhamba ngebhayisikili, imoto yezemidlalo, ukushushuluza ezintabeni, ukukhanya kwezulu, njl. Ingqalelo yabo kukuba zenziwe ngezinto ezizinzileyo, ngoko ezi glasi zikhusela amehlo ekufumaneni iindidi ezinamandla.
Izikhuselo ezikhuselekileyo zokubhukuda kunye ne-diopters zikhusela kwimisebe ye-UV, kunye neengubo ezikhethiweyo ngaphakathi kwilensi zibavimbela ukuba bangabikho. Xa ukhetha lolu hlobo lweiglasi, kufuneka kukhunjulwe ukuba amanzi aphucula umphumo weelensi.
Iiglasi zokujonga ukuqhuba ngokuqhubela phambili, ngokungezelela ukulungiswa kwamehlo, kufuneka ziqinisekise ukupheliswa kwe-glare (polarization), ukudala ukuhluke ngakumbi. Iilazi ezinjalo zinokuthi zenziwe kunye neefom photochromic.
Kubantu abanokubukeka kakubi, ngoku unokukhetha okanye wenze ngokwezifiso izibuko zelanga kunye ne-diopters. Ukuze ungabandakanyi iziphumo ezingenakunqwenelekayo, kufuneka ukhethe imodeli yeiglasi ezinemibala (ukuze iilensi ziye kwindiza efanayo phambi kwamehlo).
Uninzi xa usebenzisa iikhomputha zeekhompyutheni zekhompyutheni, oko kukubonga ngezihlomelo ezikhethekileyo, ukunciphisa ubunzima emehlweni. Ukuba unengxaki ebonakalayo, kunokwenzeka ukudibanisa iilazi ezinjalo kunye nama-lens. Enye indlela yokusebenzisa iiglasi zeekhomputha kunye ne-diopters ezifanelekileyo.
Ukuba awukwazi ukumbona kakuhle, kwaye ngoko ukuchithwa kwamehlo akufani, iiglasi ezikhethiweyo ezahlukeneyo zikhethiweyo.
Kubantu abaninzi abanokubukeka kakubi, iimbini ezibini zeziglasi zifuneka - ngokuba "umgama" kunye "ngokusondeleyo" (xa ufunda). Kodwa kukho ithuba lokusebenzisa iiglasi enye kunye neengcingo, kokubili kokufunda nakwezinye iimeko. IiLenses kulezi glasi zibizwa ngokuba yi-multifocal.
Iingongoma zeroopters zero (iiglasi eziqhelekileyo) zisetyenziselwa ukufumana ifowuni, ukugxininisa umfanekiso.
Ukuba ufuna iifilimu zefestile kunye neengqungquthela, nceda uqaphele ukuba kwixesha elizayo kwifestile kuya kuba yiiglasi "iliso lekati", "iliso le-dragonfly", iiglasi kwiifom ezinkulu, kunye nezohlobiso.