Koma kupitirira kukhala mandala ambiri popanda mizere, magalasi opita patsogolo amathandizira anthu omwe ali ndi Presboria kuti awonenso bwino patali konse.
Ubwino wa magalasi opita patsogolo pa ma bifoctals
Ma tambala a Biocal Speens ali ndi mphamvu ziwiri zokha: imodzi yowona m'chipindacho ndi inayo kuti muwone pafupi. Zinthu zomwe zili pakati, ngati chophimba pakompyuta kapena zinthu zomwe zimagulitsa m'mphepete mwa shelufu, nthawi zambiri zimakhala zopanda pake ndi ma bifocdals.
Kuyesera kuwona zinthuzo "zapakatikati" izi zikuwonekeratu, zolesera za ma bifocal ziyenera kuti zikuyenda pansi ndikuyang'ana pamwamba kenako pansi pa mabisi awo, kuti mudziwe gawo liti la mandala limagwira bwino ntchito.
Zoyenda pang'onopang'ono zimasokoneza masomphenya achilengedwe omwe mudakondwera nawo isanayambike Presbapia. M'malo mongopereka maluso awiri a mandala okha monga mabifi (kapena atatu, monga ma trifocals), mandala opita patsogolo kwambiri ndi malingaliro owona, "mitundu yambiri yamphamvu ya mandala ambiri amayang'ana mbali zonse.
Masomphenya achilengedwe opanda "kudumpha"
Mizere yowoneka mu ma bifocsial ndi ma trifocals ndi mfundo komwe zikuchitika mwadzidzidzi. Komanso, chifukwa cha kuchuluka kwa maudzu a mandala mu mabifoloko ndi ma trifocals, kuyambika kwanu ndi magalasi ndi ochepa. Kuti muwone bwino, zinthu ziyenera kukhala pamtunda wautali. Zinthu zomwe zili kunja kwa mtunda wokutidwa ndi ma abifocal kapena ma rens opeza zidzakhala zosayenera ndikusintha mu mphamvu ya mandala.
Magawo opita patsogolo, kumbali inayo, amakhala osalala bwino, osasunthika a ma lens a mandala masomphenya owonekera patali. Magawo opita patsogolo amapereka mwachilengedwe mwachilengedwe popanda "kudumpha."
Mphamvu yopita patsogolo magalasi amasintha pang'onopang'ono mpaka kufika pa mandala, kupereka manda oyenera kuwona momveka bwino patali.
Imapereka masomphenya omveka bwino pamtunda wonse (m'malo mongoyang'ana mtunda wa awiri kapena atatu osiyana).
Kwa masomphenya abwino kwambiri, chitonthozo ndi mawonekedwe ake, mutha kusankha mbali zambiri kuti muzowerere zochulukirapo kuposa mandala am'mbuyomu. Mutha kusunthira patsambahttps://www.universertical.com/wideview-Product/Kuti muwone zambiri za mapangidwe athu opita patsogolo.