Tanthauzo: Emmetropia ndilo liwu logwiritsidwa ntchito pofotokoza masomphenya a munthu pamene palibe cholakwika chilichonse choloweza kapena kutayika. Emmetropia amatanthauza diso lomwe liribe zolakwika. Zithunzi zopangidwa pa diso la emmetropic zimatsindika mwatsatanetsatane, momveka bwino komanso molondola.
Maso omwe ali ndi emmetropia samafuna kuwongolera masomphenya . Pamene munthu ali ndi emmetropia m'maso onsewo, munthuyo akufotokozedwa kukhala ndi masomphenya abwino.
Pamene diso liri emmetropic, kuwala kowala komwe kumalowa m'diso kuchokera patali kumakhala koyang'ana bwino pa retina.
Ngati diso liri lachilendo kutalika kapena cornea ndi losazolowereka, mwayi sungakhale emmetropic. Ngati diso la munthu liri lalitali kuposa laling'ono, kuwala kungakhale koyang'ana kutsogolo kwa retina m'malo mwachindunji. Izi zingayambitse kuyang'ana pafupi. Ngati diso la munthu ndi lalifupi kwambiri, zithunzizo zimayang'ana kumbuyo kwa retina. Izi zimayambitsa kutalika.
Chikhalidwe cha emmetropia kapena mmene diso limakhudzira chidwi cha asayansi ndi madokotala a maso. Kudziwa momwe mwana wakhanda akukula poyendetsa maselo amatha kuwawonetsa njira zatsopano zothetsera zolakwitsa, monga kuyang'anitsitsa ndi kuyang'anitsitsa kapena kuthandizira kupeza njira zowonjezera kuwonjezeka kwa zolakwika zozizira. Mchitidwe wa emmetropization sungamvetsetse bwino koma umalingaliridwa kuti umapezeka mwa zowoneka zowonekera, ubongo wa ubongo, majini ndi njira zina zomwe defocus zingakhudze kukula kwa diso.
Ngati simuli emmetropic, ndiye kuti muli ndi vuto la refractive. Zitsanzo za zolakwika za refractive ndi zotsatirazi.
- Pafupi ndi kuwona : Kuyang'anitsitsa, kapena myopia, ndi chikhalidwe chomwe zinthu zakutali zikuwoneka bwino, koma zakutali zimakhala zovuta. Kuyembekezera kuyang'anitsitsa kungatengedwe ndipo nthawi zambiri kumawululidwa ali mwana. Komabe, mungathe kukhala ndi chidwi choyang'ana poyambirira. Anthu omwe amapanga myopia akakula, nthawi zambiri sakhala ndi chidwi choyang'ana.
- Kuganizira zam'tsogolo : Kuganizira zam'tsogolo, kapena hyperopia (komwe kumatchedwanso hypermetropia), nthawi zambiri zimayambitsa zinthu zakutali kuti ziwoneke bwino, koma zinthu zowoneka ngati zosaoneka. Nthawi zambiri anthu amatha kuona zinthu mofulumira. Pamene wina ali ndi maonekedwe akuluakulu, kutalika kwawo kungakhale kophweka kuwonjezera pa masomphenya awo pafupi. Anthu ambiri amalephera kuyang'ana kwa presbyopia, zolakwika zomwe zimachitika nthawi zambiri zimapezeka zaka zoposa 40.
- Astigmatism : Astigmatism imapezeka nthawi imene cornea ili ndi mphutsi yosasinthasintha. The cornea ndi yokhotakhota kwambiri mu njira imodzi, yopangitsa masomphenya ophwanyika. Astigmatism ingayambitse masomphenya pamtunda wonse, ndipo nthawi zambiri imakhala ndi maso kapena maso. Anthu ambiri ali ndi mayendedwe ochepa chabe. Mankhwala aakulu a astigmatism amachititsa kusokonezeka kuwonjezera pa masomphenya ophwanyika. Nthawi zambiri nthawi zambiri zimakhala zovuta kuwona masomphenya 20/20.
- Presbyopia : Presbyopia ndi ukalamba wodala wa diso. Ndikutayika kwa mitsempha yomwe imapezeka ndi ukalamba, zomwe zimayambitsa kuyika pambali. Asayansi akukhulupiliranso kuti kuwonjezera pa kutayika kwa disolo, minofu yomwe imapangitsa kuti disolo lisinthe, limatchedwa kuti ciliary body, limayambanso kugwira ntchito. Presbyopia kawirikawiri imakhala yaikulu pambuyo pa zaka 40-45 zaka koma anthu pakati pa 35-40 akhoza kusonyeza zizindikiro zoyambirira malinga ndi momwe akuonera, ntchito, ndi moyo wawo