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1、眼睛大的人更容易近视？Wonderwhyyou'reshort-sighted?Havingbeautifulbigeyescouldbetoblame[2013-09-0311:17]来源:中国日报网字号［大］［中］【小］回一双美丽的大眼睛通常都被视为相貌上的优势，可英国眼科专家却表示，大眼睛的人更容易得近视眼。所以从这个角度來说，大眼睛反而成了一个弱点。专家指出，近视眼是山于外界光线焦点没有正确落在视网膜上而造成的，人眼睹的人因为眼球太大而导致外界光线黒点没冇落在视网膜上，而是落在视网膜前方，因而无法在视网膜上形成请晰的图像。与此相反，眼睛小的人更容易得远视眼，也就是外界光线焦点落在视
2、网膜后方。英国患近视眼的人在不断増加，日前全国约有一半人是近视眼。专家表示，眼睛前后直径平均值为24毫米，比这个数值髙出1毫米，眼睛就会明显近视：而爲出2到5毫米则是窩度近视。专家解释称，现在近视的人越來越多可能是因为大家待在室内的时间过多，外界自然光线会让眼球自动调节生长状态，避免眼球过大，而室内的人造光线则没有这个功效。RebeccaLargehasalwaysbeentoldherbigbrowneyesareherbestfeature・LikethoseofHollywoodstarsAngelinaJolieandAudreyHepburn,Rebecca*seyesarere
3、gardedbymostasasignofbeauty.Yeteyeexpertshaverealisedthatfarfrombeinganasset,largeeyescanactuallybeaweakness,andmakesomeonemorepronetobeingshort-sighted・Thiscondition,alsoknownasmyopia,causesdistantobjectstoappearblurred,whilecloseonescanbeseenclearly.Itiscausedbylightnotproperlyreachingtheretina,
4、thelight-sensitiveareaatthebackoftheeye・Expertsbelievethismightbebecausetheeyeballgrowstoolarge,whichcausesthelighttofocusinfrontoftheretina,ratherthanonit.Short-sightednessisontheriseinBritain,withupto50percentofpeoplenowestimatedtohaveit.Onepossibleexplanationforthisisthatoureyeballsaregettingla
5、rgerbecausewearespendingmoretimeindoors・Alackofoutdoorlightinourearlyyearscausesthesizeoftheeyeballtoincrease.Butthelargertheeyeball,themorelikelyapersonistobeshort-sighted,explainsAndyLuff,aconsuitantophthalmicsurgeonatOptegra,achainofprivateeyehospitals.Whilebigeyescancertainlylookbeautiful,thef
6、actisthatifyoureyesareslightlytoobig,thiswillcauseyoutosuffershortsight.Iftheeyeballistoobig,thelightfocusedbythelensoftheeyedoesnotreachthebacktheretina,whereimagesareprocessed・Iftheeyeisonly1mmIongerthan24mm(theaveragesizefrorrfronttoback)apersonwillbesignificantlyshort-sighted・Longerthantheaver
7、ageby2to5mmwillmakeyouhighlyshort-sighted/DrLuffexplainsthatinthepastwethoughttheeyegrewtoolargeandbecameshort-sightedduetogeneticfactors・'Althoughgeneticsisstillthemostimportantreasonbehindshort-sightedness,lack
