Girman ruwan tabarau a cikin tabarau yana tasiri da abubuwa da yawa, daga cikinsu ikon ruwan tabarau shine babban mahimmanci.Kaurin ruwan tabarau na Babban Myopia yana da kauri fiye da na ƙananan Myopia.Koyaya, idan ya zo ga kauri gabaɗaya, diamita na Lens shima yana da mahimmanci, kuma zaɓin ƙaramin firam na iya rage kaurin ruwan tabarau.Siffar Lens kuma yana da mahimmanci, kamar Myopia a cikin kauri mai kauri na gefen lens mai kauri, Hyperopia a tsakiyar kauri na Lens Convex da na gefen bakin ciki.
Ma'anar refractive (Yuni 20) na ruwan tabarau wani abu ne mai mahimmanci da kuma abin da ke bawa majiyyaci damar sarrafa kauri na Lens.Fihirisar refractive shine rabon adadin da haske ke wucewa ta wani matsakaici (kamar gilashi, ruwa, robobi, iska) zuwa adadinsa a cikin injin da babu ruwa.Mafi girman ma'aunin refractive, ƙananan watsawar haske a cikin matsakaici, kuma mafi bayyananniyar jujjuyawar haske.Don haka, ruwan tabarau mai babban fihirisar refractive yana karkatar da haske da inganci kuma don haka ya fi sirari fiye da ruwan tabarau mai ƙaramin ma'anar refractive.
An yi gilashin gilashi shekaru aru-aru, kuma wasu marasa lafiya har yanzu suna nace ga ruwan tabarau na gilashi saboda suna jin suna ba su mafi kyawun gani.Gilashin gilashin zamani an yi su ne daga Gilashin Crown, wani abu mai ƙarancin ɓarna mai chromatic da juriya ga karce.Gilashin Crown yana da babban maƙasudin refractive, har ma sama da na manyan ruwan tabarau na filastik.Duk da haka, saboda girmansa, gilashin rawanin nauyi fiye da ruwan tabarau na filastik tare da ma'anar refractive iri ɗaya, kodayake ruwan tabarau na filastik yawanci suna da kauri.Marasa lafiya sukan zaɓi ruwan tabarau masu sauƙi, wanda shine dalilin da ya sa suke zaɓar ruwan tabarau na filastik akan gilashin kambi.
Daidaitaccen Filastik don gilashin firam shine Columbia Resin-39(CR-39) .Wannan abu ne mai kyau na ruwan tabarau, mai jurewa, kuma yana auna rabin kawai kamar ruwan tabarau iri ɗaya.Duk da haka, ƙananan fihirisar ta na nufin cewa Lens yana da ɗan kauri lokacin da aka yi shi zuwa gilashin diopter masu girma.
An ƙera kayan ruwan tabarau na filastik iri-iri, wanda ya haifar da mafi girman maƙasudi amma mafi ƙaranci, ruwan tabarau masu sauƙi.Irin su polycarbonate (1.586), polyurethane (1.595) har ma da gilashin kayan aiki na musamman (1.70).Wadannan ruwan tabarau ba su da kauri fiye da na sauran marasa lafiya na myopic, yayin da suke samar da adadi mafi girma na tsayi.Duk da haka, wasu daga cikin waɗannan kayan suna da manyan ɓarna fiye da ƙananan kayan ƙima kuma ba a jure su cikin sauƙi ba.Yawancin waɗannan kayan sun fi laushi, sun fi juriya ga karyewa fiye da gilashin ko filastik CR-39, amma sun fi dacewa da zazzagewa.
Lokacin aikawa: Yuli-28-2021