Osadandaula — sizikutanthauza kuti muyenera kuvala ma bifocal kapena ma trifocal osasangalatsa. Kwa anthu ambiri, ma lens otsogola opanda mzere ndi njira yabwino kwambiri.
Kodi magalasi opita patsogolo ndi chiyani?
Magalasi opita patsogolo ndi magalasi opanda mizere yambiri omwe amawoneka ofanana ndi magalasi owonera kamodzi. Mwanjira ina, magalasi opita patsogolo adzakuthandizani kuwona bwino patali kulikonse popanda "mizere iwiri" yosasangalatsa (ndi yodziwika bwino) yomwe imawonekera mu magalasi oyenda bwino a bifocal ndi trifocal.
Mphamvu ya ma lens opita patsogolo imasintha pang'onopang'ono kuchokera pamalo ena kupita pamalo ena pamwamba pa lens, zomwe zimapangitsa kuti lens ikhale ndi mphamvu yoyenera yowonera zinthu bwino patali kulikonse.
Koma ma Bifocal ali ndi mphamvu ziwiri zokha za lenzi — imodzi yowonera zinthu zakutali bwino ndi mphamvu yachiwiri m'munsi mwa lenzi yowonera bwino pa mtunda wowerengeka wowerengera. Kulumikizana pakati pa madera amphamvu osiyana awa kumatanthauzidwa ndi "mzere wa bifocal" wooneka womwe umadula pakati pa lenzi.
Magalasi opita patsogolo nthawi zina amatchedwa "magalasi opita patsogolo opanda mzere" chifukwa alibe mzere wooneka wa magalasi opita patsogolo. Koma magalasi opita patsogolo ali ndi kapangidwe kapamwamba kwambiri ka multifocal kuposa magalasi opita patsogolo kapena ma trifocal.
Magalasi apamwamba kwambiri, nthawi zambiri amapereka chitonthozo chabwino komanso magwiridwe antchito, koma palinso mitundu ina yambiri ndi ntchito zina, monga lenzi yotsogola ya photochromic, lenzi yotsogola ya bluecut ndi zina zotero, ndi zinthu zosiyanasiyana. Mutha kupeza yoyenera patsamba lathu.https://www.universeoptical.com/progressive-lenses-product/.
Anthu ambiri amayamba kufunikira magalasi a maso a multifocal nthawi ina akakwanitsa zaka 40. Apa ndi pamene kusintha kwabwinobwino kwa ukalamba m'diso kotchedwa presbyopia kumachepetsa kuthekera kwathu kowona bwino pafupi. Kwa aliyense amene ali ndi presbyopia, magalasi opita patsogolo ali ndi ubwino waukulu wowona ndi kukongola poyerekeza ndi magalasi achikhalidwe a bifocal ndi trifocal.
Kapangidwe ka multifocal ka ma lens opita patsogolo kamapereka zabwino zotsatirazi:
Imapereka masomphenya omveka bwino pa mtunda uliwonse (osati pa mtunda wokha wowonera kawiri kapena katatu).
Zimachotsa "kudumpha kwa chithunzi" komwe kumayambitsidwa ndi ma bifocal ndi ma trifocal. Apa ndi pomwe zinthu zimasintha mwadzidzidzi momveka bwino komanso malo owonekera pamene maso anu akuyenda pamizere yooneka m'magalasi awa.
Chifukwa chakuti palibe "mizere ya bifocal" yooneka mu ma lens opita patsogolo, imakupatsani mawonekedwe achichepere kuposa ma bifocal kapena ma trifocal. (Chifukwa ichi chokha chingakhale chifukwa chake anthu ambiri masiku ano amavala ma lens opita patsogolo kuposa chiwerengero cha omwe amavala bifocal ndi trifocal pamodzi.)