Madokotala a maso amayesa kuponyera mawu akuti "20/20" pang'ono pokha. Nthaŵi zambiri, popanda kuganiza, madokotala owona ndi opaleshoni ya maso akugwiritsa ntchito mawu akuti 20/20 popanda kuwaphunzitsa kwenikweni odwala awo zomwe kwenikweni amatanthauza. "Bambo. Smith, iwe uli ndi masomphenya 20/20 ... kodi sizodabwitsa? "Ambiri azindikira kuti kukhala ndi masomphenya 20/20 ndi okwanira, mwachibadwa kapena chinthu chabwino.
Nthawi zonse mumayang'ana pulogalamu yamakono, 20/20? Ndilo dzina labwino pawonetsero wamakono omwe cholinga chawo chikuwunikira kapena kuwonekera bwino kwambiri pa nkhani zina zotchuka.
Kuyeza Masomphenya
Masomphenya a anthu ndi ovuta. Masomphenya athu ali ndi maulendo ambiri koma odziwa zowona maso amafuna njira ina yowerengera kapena kuyesa masomphenya. Ngati tingathe kuyeza masomphenya, tikhoza kudziwa momwe tingakhalire kutali kapena momwe tingakonzekeretse kuti tibweretse munthu wina ku zomwe timaona ngati masomphenya. Zingakhale zovuta kutanthauzira masomphenya ngati tangolemba, "Masomphenya ali pafupi" kapena "Masomphenya akuwoneka bwino." Izi sizikanakhala njira yabwino yodziwerengera. Zingakhale zolondola kwambiri kulemba masomphenya a munthu ngati 20/30. Mwanjira iyi, tikhoza kuyang'ana nthawi yambiri momwe masomphenya athu angasinthire kapena sangasinthe.
Njira ya Snellen ya Visual Acuity
Kwa anthu ambiri, kudabwa kwa diso kuli kovuta.
Chifukwa diso ndi masomphenya anu ali mbali ya ubongo wanu ndi dongosolo lamanjenje, pali zinthu zambiri pazinthu zadokotala. Yoyamba ndipo mwinamwake chiyeso chofunikira kwambiri ndi masomphenya athu oyambirira, kapena maonekedwe oyambirira. Ichi ndi gawo la masomphenya omwe timagwiritsa ntchito pamene tigwiritsa ntchito diso lathu pazinthu kuti tiwone.
Ku United States, timagwiritsa ntchito njira ya Snellen yooneka bwino. Nambala yaikulu, 20, imatanthawuza kutalika kwayeso pamapazi. Asayansi anaganiza pa mapazi makumi awiri chifukwa chirichonse chomwe ife tikuchiwona icho chiri mamita 20 kapena kutali chikuwoneka kuti ndi chopanda malire. Iwo anafika pamapeto amenewo chifukwa cha mmene mafunde amawonekera komanso momwe diso lathu limayendera zinthu. Mu diso labwino, lopangidwa mwangwiro laumunthu, mitsempha yowunikira imakhala yotetezeka kwambiri poyang'ana zinthu pamtunda wopitirira 20 kapena kupitirira. Zinthu zikayamba kuyandikira pafupi ndi maso athu kuposa mamita 20, diso lathu limayamba kusintha cholinga chake kuti likhale loyera.
Komanso, njira ya Snellen imaganiza kuti diso labwino liri ndi ubwino wabwino ngati lingathetse tsatanetsatane wa kalata pamtunda wa mamita 20. Zomwezo zikufotokozedwa ngati mtunda umene chigawo chilichonse cha kalata, mwachitsanzo, kalata E, ili ndi msinkhu wazing'ono wa mphindi imodzi ya arc. Mphindi imodzi ya arc ikufanana ndi 1/60 ya digiri. Kalata yonseyi imakhala mphindi zisanu. Kuti mumvetse izi, muyenera kubwerera ku geometry ndikukoka katatu ndikuyang'ana mbali ya katatu. Kutha kwakukulu kwa katatu ndiko kalata E, ndi zigawo zisanu ... mpiringidzo wa E, danga, mbiya yapakati, danga ndi mtanda wa diso.
Mbali ndi mphindi zisanu za kalata yonse ndi miniti imodzi ya arc pa bar.
Kotero Kodi 20/400 Imatanthauza Chiyani?
Mwachitsanzo, nambala yapansi mu 20/400 ndi mtunda umene tsatanetsatane wa kalata iliyonse imaphatikizapo mphindi imodzi yokha. Kotero, pamene munthu aima mamita 400 kuchokera ku E yaikulu pa tchati cha diso, chinthu chilichonse cha E chimaphatikizapo mphindi imodzi yokha. Izi zinakhala zofanana chifukwa diso la umunthu ndi machitidwe a ubongo mu ubongo zimatiloleza kuti tisankhe mosavuta pakati pa makalata ndi zinthu zomwe zimapangitsa mphindi imodzi yokha.
Njira inanso yoganizira izi ndikutanthauza kuti ngati wina ayesedwa kuti ali ndi masomphenya 20/50, ndiye kuti munthuyo ayenera kusuntha mpaka mamita makumi asanu ndi awiri kuti akwanitse kuthetsa tsatanetsatane kwambiri mu kalata, pomwe mnzanu weniweni akhoza kuima kubwerera kumbuyo kwa mamita 50 ndikukonzekera tsatanetsatane kwambiri.
Kugwiritsira ntchito Mirror mu Mapulogalamu
Ngati mumaganizira za izi, zipinda zamakono zofufuzira zimagwiritsa ntchito sizitali mamita 20. Chochititsa chidwi, kungoyika galasi kumangofanana ndi kutalika kwa mtunda wa mamita 20 bwino. Ngati chipinda chili mamita khumi, kuyika galasi kuti uwononge tchati cha diso kumapangitsa kuti chipindacho chiwoneke mamita 20 m'litali. Ochita masewera olimbitsa thupi apindula kwambiri poyang'ana magalasi a maso molingana ndi mtunda weniweni kuchokera ku diso la wodwala kupita pagalasi ndiyeno kuchokera pagalasi kupita ku chojambula cha diso. Pakubwera ma chati a maso a makompyuta, kuchepera kumakhala kophweka.
Kodi 20/20 Ndi Yeniyeni?
Tiyenera kudziwa masomphenya 20/20 kukhala masomphenya oyenera. Komabe, mofanana ndi kuchuluka kwa chithandizo chamankhwala, pali "mtundu" wa masomphenya. Ena a ife tingawonere pang'ono ndi 20/20, titi 20/25, ndipo enafe tikhoza kuona bwino kusiyana ndi 20/20, titi 20/15, ndipo tikuwonekeratu kuti ndi oyenera. Mapepala ambiri a maso akukonzekera kukula kwa kalata mpaka kufika 20/10, chifukwa sizingatheke kupeza munthu amene amawona bwino kuposa 20/10. Kutsimikiza kwa masomphenya athu oyambirira ndi ofanana ndi mawonekedwe a makompyuta apamwamba. Ngati ma pixel ndi abwino kwambiri ndipo atseke pamodzi, chisankho chazitsulo ndi bwino. Ojambula pa TV amaphunzira zooneka bwino . Pangakhale mfundo pamene chisankho china cha TV chomwe chili chapamwamba kuposa momwe munthu amawonera bwino kwambiri sizingapangitse kusiyana. Ngati chisankho cha TV chikuposa momwe diso la munthu lingathetsere, ndi chiyani?
SOURCE: Njira zothandizira odwala m'mimba, Eskridge, J, Amos, J., Bartlett, J., JB Lippincott Company, 1991.