Txoj kev txhim kho tas li ntawm cov thev naus laus zis kho mob tso cai rau ntau lab tus tib neeg thoob plaws ntiaj teb kom rov pom lawv txoj kev ploj thiab ua rau lub neej tag nrho. Ib txoj hauv kev zoo tsim kom tsis txhob muaj presbyopia, uas tshwm sim nrog lub hnub nyoog ntawm cov neeg feem coob, yog siv ob lossis ntau lub iav tsom iav. Tau kawg, qhov no tsis yog ib txwm yooj yim, thiab ntawm no bifocal tsom iav tuaj rau kev cawm, uas muab cov khoom ntawm ob khub.
Feem ntau, ib nrab ntawm lub khob hauv cov iav zoo li no tso cai rau koj pom cov khoom nyob deb zoo, thiab ib nrab qis tso cai rau koj paub qhov txawv ntawm cov khoom nyob ze. Tej zaum yuav muaj ntau dua li cov tsom iav hauv tsom iav, tom qab ntawd cov iav bifocal tuaj yeem dhau los ua trifocal lossis txawm tias multifocal.
Lub tswv yim ntawm lawv cov kev tsim tau pom zoo los ntawm qhov xwm txheej nws tus kheej, qee hom ntses muaj lub zeem muag bifocal, uas tso cai rau koj kom pom cov khoom hauv qab ntawm lub pas dej thiab tib lub sijhawm ua tib zoo saib xyuas cov noog. ntawm cov tsiaj los ntawm saum toj no. Nws ntseeg tau tias thawj lub iav bifocal tau tsimBenjamin Franklin, uas tau muab ob lub khob iav rau hauv ib qho.
Kev nthuav dav ntawm lub tswv yim no tau thov los ntawm Israeli tus kws tshawb fawb Zeev Zalevsky, uas tau muab cov tsom iav sib xyaw ua ke uas cov iav bifocal tau yooj yim siv ntau dua. Tsis muaj ib tug ntse ciam teb ntawm cov iav hauv nws lub tsom iav. Lub teeb pom kev los ntawm qhov deb thiab ze ntawm cov khoom yog tsom mus rau hauv ib qho txuas ntxiv, uas npog tag nrho retina ntawm lub qhov muag. Qhov no tso cai rau koj pom txhua yam khoom sib npaug zoo. Cov tsom iav no ua rau koj ob lub qhov muag tsis nkees thiab siv sijhawm tsawg los hloov kho lawv.
Thaum sim lawv, qhov nthuav dav tau sau tseg. Nws muab tawm tias lawv tuaj yeem kho ob qho tib si qhov muag tsis pom kev. Ntawd yog, cov iav no tsis tuaj yeem tiv taus cov kab mob muaj hnub nyoog no, lawv kuj tseem muaj txiaj ntsig zoo rau kev tiv thaiv.
Kev txhim kho ntawm cov thev naus laus zis siab kuj tseem muab sijhawm ntxiv hauv kev txhim kho ntawm qhov teeb meem ntawm kev khaws lub zeem muag. Tam sim no cov iav bifocal tau tsim nyob rau hauv lawv cov khoom siv hluav taws xob. Nyob rau hauv cov ntaub ntawv no, ib tug kua siv lead ua tshuaj ntsuam yog muab tso rau ntawm ob lub tsom iav, uas xa cov duab rau peb.
Thaum cov khoom siv hluav taws xob ntawm bifocals, cov neeg tsim khoom tau ntsib nrog txoj haujlwm ntawm kev ua kom cov duab zoo. Tsis tas li ntawd nthuav yog qhov tsis zoo ntawm qhov tshiab kom nce lossis txo cov duab, nrog rau autofocus. Thawj qhov qauv yog muab los ntawm PixelOptics, uas txuas ntxiv nws txoj kev tshawb fawb hauv cheeb tsam no.
Tom qab sab laj nrog koj tus kws kho mob, koj tuaj yeem yuav khoom bifocals. Lawv cov nqi sib txawv nyob ntawm lub tuam txhab.manufacturers thiab cov khoom zoo. Tab sis qhov tseem ceeb hauv qhov teeb meem no yog qhov raug xaiv tsis tau ntawm cov iav zoo li no. Qhov no cuam tshuam rau lub sijhawm hloov kho zaum kawg, uas tuaj yeem siv li kaum hnub txij li pib siv.
Yog tias koj ua haujlwm nrog cov khoom uas nyob ze koj ntau lub sijhawm, ces lub iav qis yuav tsum loj dua qhov saum toj. Thiab, raws li, thaum ua hauj lwm nrog cov khoom nyob deb, yuav cov iav nrog ib cheeb tsam loj ntawm cov iav saum toj. Qhov no yuav pab koj hloov kho sai sai rau cov khoom tshiab thiab ua rau lub neej ua tiav.
