Daahfurka alaabta muraayadaha muraayadaha

Dhumucda muraayadaha muraayadaha waxaa saameeya arrimo badan, kuwaas oo awoodda muraayadda ay tahay qodobka ugu muhiimsan.Dhumucda muraayada ee Myopia Sare waa ka dhumuc weyn tahay kan Myopia hoose.Si kastaba ha ahaatee, marka ay timaado dhumucda guud, dhexroorka muraayada ayaa sidoo kale muhiim ah, iyo doorashada jir yar waxay si weyn u dhimi kartaa dhumucda muraayada.Qaabka Lensku sidoo kale waa muhiim, sida Myopia oo ku taal qaybta dhumucda weyn ee lens-ka concave, Hyperopia ee qaybta dhexe ee dhumucda lens-ka Convex iyo durugsan dhuuban.

Tusmada dib-u-celinta (June 20) ee lensku waa sifo muhiim ah iyo arrin u oggolaanaysa bukaanka inuu xakameeyo dhumucda muraayadda.Tusmada dib-u-celinta waa saamiga heerka uu iftiinku maraayo meel dhexaad gaar ah (sida galaas, biyo, balaastiig, hawo) ilaa heerka uu maraayo.Markasta oo ay sareeyso tusaha wax-soo-celinta, hoos ayuu u dhigayaa heerka gudbinta iftiinka ee dhexdhexaadka ah, waxaana aad u muuqda soo-celinta iftiinka.Haddaba, muraayadda leh index refractive-sare ayaa si wax ku ool ah u soo celisa iftiinka sidaas darteedna waa ka khafiifsan yahay muraayadda leh index refractive hoose.

Muraayadaha ayaa laga sameeyay dhalo qarniyo badan, bukaanada qaarna waxay wali ku adkeysanayaan muraayadaha muraayadaha sababtoo ah waxay dareemayaan inay siinayaan tayada muuqaalka ugu fiican.Muraayadaha muraayadaha casriga ah waxay ka samaysan yihiin muraayadda Crown, shay leh aberration chromatic hooseeya iyo iska caabinta xagashada.Muraayada Crown waxa ay leedahay index refractive sare, xitaa ka sarreeya muraayadaha caagagga badan.Si kastaba ha ahaatee, cufnaanta sare awgeed, muraayadda taajku way ka culus tahay muraayadaha caagga ah ee leh tusmada wax-soo-celinta ee isku midka ah, inkastoo muraayadaha caagga ah ay badanaa ka dhumuc weyn yihiin.Bukaan-socodka waxay u muuqdaan inay doortaan muraayadaha khafiifka ah, taas oo ah sababta ay u doortaan muraayadaha caagga ah ee muraayadda taajka.

Caadiga caadiga ah ee muraayadaha jirku waa Columbia Resin-39(CR-39) .Kani waa qalab muraayad wanaagsan leh, xoqan u adkaysta, oo miisaankiisu kala badh ka yahay muraayadaha muraayadda isku midka ah.Si kastaba ha ahaatee, tusmihiisa dib u soo celinta hooseeya waxay ka dhigan tahay in Lensku uu dhumuc weyn yahay marka laga dhigo muraayadaha-diopter-ka sare.

Qalab kala duwan oo muraayado caag ah ayaa la sameeyay, taasoo keentay tusmaynta wax-soo-celinta sare laakiin khafiif ah, muraayado fudud.Sida polycarbonate (1.586), polyurethane (1.595) iyo xitaa muraayadaha khaaska ah (1.70).Muraayadahani kama dhumuc weyn yihiin kuwa bukaannada kale ee miyir-qabka ah, iyagoo bixinaya tiro sare oo heerar dherer ah.Si kastaba ha ahaatee, qaar ka mid ah alaabtan ayaa leh cillado ka weyn kuwa hoose ee tusmooyinka tusaha oo aan si fudud loo dulqaadan karin.Inta badan alaabtani way ka jilicsan yihiin, way ka adkaysan badan yihiin jabinta dhalada ama balaastiga CR-39, laakiin aad bay ugu nugul yihiin xagashada.