Dab tsi yog qhov slab tawm ntawm bifocal?
Dab tsi yog qhov slab tawm ntawm bifocal?

Video: Dab tsi yog qhov slab tawm ntawm bifocal?

Video: Dab tsi yog qhov slab tawm ntawm bifocal?
Video: Qhov yuav tau ceev faj thiab txaus ntshai txog ntawm tus tshuaj txuj lom qaib no yog dab tsi tiag 1 2024, Lub Xya hli ntuj
Anonim

Dab tsi yog slab - tawm ? Nws yog cov txheej txheem tshwj xeeb tsom iav siv los tshem tawm qhov tsis xav tau prism thaum saib los ntawm thaj chaw nyeem ntawv (feem ntau yog bifocal ) ntawm dav sib txawv lens powers. Slab tawm ua pov thawj tias daim duab ze yuav tsis raug tshem tawm.

Yog li ntawd, lub lens twg koj slab tawm?

Slab - tawm muab lub hauv paus (BU) prism thiab siv rau qhov feem ntau rho tawm, lossis tsawg dua ntxiv lens nyob rau hauv txoj kab nruab nrab ntawm txoj kab nruab nrab kom txo qis qis qis qis (BD) vim yog qhov rov qab lens . Slab - tawm tuaj muab tso rau hauv iav lossis yas lens , txawm hais tias txhua tus yog tsim nyob rau hauv ib txoj kev sib txawv.

Ib sab saum toj no, Optometrists puas tau nyiaj ntawm tsom iav? 2. Qhov muag qhov muag ua nce 62% ntawm ib tus kws kho qhov muag nyiaj hli. Nws tsis yog qhov xav tsis thoob tias koj tau txais qhov muag muag tom qab txhua qhov kev kuaj qhov muag. Rau kev xyaum ua ntiag tug cov kws kho qhov muag , tshaj tawm 62% ntawm lawv cov nyiaj hli los ntawm kev muag cov tsom iav qhov muag thiab cov tsom iav.

Zoo sib xws, dab tsi yog prism tswj bifocals?

Txawm li cas los xij, BS EN ISO 13666: 2012 txhais a prism - tswj bifocal (lossis multifocal) raws li lub lens uas nws txoj kev tsim kho tso cai rau qee tus neeg ywj pheej tswj ntawm prismatic effect lossis kho qhov muag nruab nrab ntawm ntau ntu ntawm lub lens.

Yuav ua li cas slab tawm xam?

Txiav txim siab nrug deb ntawm qhov chaw kho qhov muag ntawm lub iav tsom iav mus rau qib nyeem ntawv. Siv Prentice Txoj Cai rau xam tus nqi ntawm ntsug prism induced nyob rau hauv txhua lub qhov muag ntawm qib nyeem ntawv. Qhov sib txawv ntawm tus nqi ntawm ntsug prism nyob rau hauv txhua lub qhov muag yog kwv yees li qhov sib npaug ntawm prism kom slabbed tawm .”

Pom zoo: