Nthaŵi zambiri maonekedwe a maso, myopia (kuyang'ana pafupi) kapena hypermetropia (kuwona bwino) amawonedwa. Kusankhidwa kwa magalasi pansi pa zolakwika zoterezi ndi cholinga chowathetsa iwo mothandizidwa ndi kufalitsa kapena kusonkhanitsa magalasi.
Kodi mungagwiritse ntchito bwanji diopter posankha magalasi?
Pakusankha magalasi wodwala ali patali pa mamita 6 kuchokera pa tebulo lapadera. Diso lirilonse limafufuzidwa mosiyana. Kuyambira pamwamba, wodwalayo amawerenga makalata a mzere uliwonse. Mndandanda womalizawu ukuwonetsa zamatsenga. Pambuyo pake, zofooka (nthawi yayitali), ndiyeno mphamvu (zochepetsera) zamagalasi zimagwiritsidwa ntchito pa diso. Wodwalayo amawerenga mzere womaliza kachiwiri, zomwe amakhoza kuziwona. Galasi lamphamvu kwambiri imasonyeza kukula kwake.
Ngati masomphenyawa akuchepa kwambiri kuchokera pa galasi lopanda pake, ndiye kuti chiwerengero cha myopia chingatheke. Izi zimachitika ndi chithandizo cha galasi la concave. Ngati galasi la concave silinathandizidwe, chifukwa cha kuwonongeka kwa maonekedwe akuwonetseratu kumamvekanso.
Mitundu ya magalasi ndi diopters
Magalasi osiyanasiyana okhala ndi diopters - magalasi-chameleons (photochromic). Amagwiritsa ntchito malonda a photochromic, omwe amasintha mtundu, mwachitsanzo, mdima, ndi machitidwe a ultraviolet miyezi. Onani kuti m'zipinda zowonongeka sizimakhala mdima, chifukwa galasi losaoneka sililola kuti ultraviolet ipite.
Magalasi oyenerera amatsitsimula mu mphindi zitatu, amdima kwa mphindi imodzi. Pankhaniyi, ma lens ayenera kusintha mtundu panthawi yomweyo.
Zitetezo zingathenso kukhala ndi diopters. Zimagwiritsidwa ntchito masewera oopsa, njinga zamoto, masewera apamsewu, kusewera m'mapiri, skydiving, ndi zina zotero. Zochitika zawo ndizoti zimapangidwa ndi zinthu zolimba kwambiri, choncho magalasi awa amateteza maso kuti asatenge tizilombo tolimba.
Zida zotetezera kusambira ndi diopters zimateteza ku mazira a dzuwa, ndipo kuvala kwapadera mkati mwa lens kumathandiza kuti asatuluke. Posankha magalasi oterewa, ziyenera kunyalidwa m'maganizo kuti madzi amachititsa zotsatira za magalasi.
Magalasi oyendetsa galimoto ndi diopters, kuwonjezera pa kukonza maso, ayenera kuonetsetsa kuti kuthetsa kuwala (polarization), kumapangitsa kusiyana kwakukulu. Magalasi oterowo angapangidwe ndi chithunzi chachithunzi.
Kwa anthu omwe ali ndi maso osauka, tsopano mukhoza kusankha magalasi ogwiritsa ntchito ndi diopters. Kuti musatenge zotsatira zovuta, muyenera kusankha mitundu yambiri ya magalasi opangidwa mozungulira (kotero kuti magalasi ali mu ndege yomweyo patsogolo pa maso).
Ambiri akamagwiritsa ntchito magalasi a makompyuta omwe amagwiritsa ntchito makompyuta, omwe, chifukwa cha mafayilo apadera, amachepetsa vutoli. Ngati muli ndi mavuto owonetsera, ndizotheka kuphatikiza magalasi oterewa ndi makina ojambulira. Njira ina ndiyo kugwiritsa ntchito magalasi apakompyuta ndi diopters yoyenera.
Ngati simungakhoze kuwona bwino, ndipo motero kusokoneza maso kuli kosiyana, magalasi okhala ndi diopters osiyanasiyana amasankhidwa.
Kwa anthu ambiri omwe ali osaona, pali magalasi awiri oyenera - "mtunda" ndi "pafupi" (powerenga). Koma pali mwayi wogwiritsa magalasi amodzi ndi ma dioptries, powerenga komanso nthawi zina. Magalasi m'magalasi awa amatchedwa multifocal.
Zolemba ndi zero diopters (magalasi ovomerezeka) amagwiritsidwa ntchito ngati mafashoni, kuti agogomeze fanolo.
Ngati mukufuna magalasi apamwamba ndi zojambulajambula, chonde onani kuti mu nyengo yomwe ikubwera mu fashoni adzakhala magalasi "maso a khungu", "diso la dragonfly", magalasi mu mafelemu akulu, ndi zokongoletsera.