Magalasi opitilira masomphenya opitilira 40
Pambuyo pa zaka 40, palibe amene amakonda kulengeza zaka zawo - makamaka mukayamba kukhala ndi vuto lowerenga zolemba zabwino.

Mwamwayi, magalasi agalasi amasiku ano amapangitsa kuti zikhale zosatheka kwa ena kukuuzani kuti mwafika “zaka zakubadwa”.

Magalasi opita patsogolo - omwe nthawi zina amatchedwa "no-line bifocals" - amakupatsirani mawonekedwe achinyamata pochotsa mizere yowoneka yopezeka mu ma lens a bifocal (ndi trifocal).

Ubwino wa magalasi opita patsogolo kuposa ma bifocals
Magalasi agalasi a Bifocal ali ndi mphamvu ziwiri zokha: imodzi yowonera chipinda chonsecho ndipo inayo yowonera pafupi.Zinthu zapakati, monga zowonera pakompyuta kapena zinthu zapashelufu ya golosale, nthawi zambiri zimakhala zosawoneka bwino ndi ma bifocals.

Kuti ayese kuwona zinthu zomwe zili pagululi "zapakatikati" izi, ovala magalasi ayenera kuweramitsa mitu yawo m'mwamba ndi pansi, mosinthana kuyang'ana kumtunda kenako pansi pa ma bifocals awo, kuti adziwe kuti ndi gawo liti la lens lomwe limagwira ntchito bwino.

Magalasi opita patsogolo amatsanzira kwambiri masomphenya achilengedwe omwe mudasangalala nawo isanayambike presbyopia.M'malo mopereka mphamvu ziwiri zokha za lens monga ma bifocals (kapena atatu, ngati ma trifocals), ma lens opita patsogolo ndi ma lens enieni a "multifocal" omwe amapereka kupititsa patsogolo kosalala, kosasunthika kwa mphamvu zambiri za lens kuti muwone bwino chipinda chonsecho, pafupi ndi mtunda uliwonse pakati.

Ndi magalasi opita patsogolo, palibe chifukwa choweramitsa mutu wanu mmwamba ndi pansi kapena kukhala ndi kaimidwe kosakhazikika kuti muwone kompyuta yanu kapena zinthu zina zazitali.

Kuwona kwachilengedwe popanda "kudumpha kwazithunzi"
Mizere yowonekera mu bifocals ndi trifocals ndi malo omwe pali kusintha kwadzidzidzi kwa mphamvu ya lens.

Pamene mzere wa wovala wa bifocal kapena trifocal udutsa mizere iyi, zithunzi zimasuntha mwadzidzidzi, kapena "kulumpha".Kusapeza bwino komwe kumabwera chifukwa cha "kudumpha kwazithunzi" kumeneku kumatha kukhala kokwiyitsa pang'ono mpaka kuyambitsa nseru.

Magalasi opita patsogolo amakhala ndi kupitilira kosalala, kosasinthika kwa mphamvu zamagalasi kuti aziwona bwino patali.Magalasi opita patsogolo amapereka kuzama kwachilengedwe kopanda "kudumpha kwazithunzi."

Magalasi opita patsogolo akhala magalasi otchuka kwambiri kwa aliyense yemwe ali ndi presbyopia yemwe amavala magalasi amaso, chifukwa cha mawonekedwe awo komanso zodzikongoletsera kuposa ma bifocals ndi trifocals.