आँख

aankh vishay soochi

sanrachana    netragolak    aansoo    netr peshiyaan    palakoan ki peshiyaan    drishti kriyavidhi    samayojan

thumb|400px|aankh evan usaki antarik sanrachana aankh (aangrezi:Eye) adhikaansh jiv jantuoan ke sharir ka avashyak aang haian. is lekh mean manav sharir se sanbandhit ullekh hai. aankh ya netroan ke dvara hamean vastu ka 'drishtijnan' hota hai. drishti vah sanvedan hai, jis par manushy sarvadhik nirbhar karata hai. drishti ek jatil prakriya hai, jisamean prakash kiranoan ke prati sanvedita, svaroop, doori, rang adi sabhi ka pratyaksh jnan samahit hai. aankhean atyant jatil jnanendriyaan haian, jo dayian-bayian donoan or ek-ek netr kotariy guha mean sthit rahati hai. ye lagabhag golakar hoti haian tatha inaka vyas lagabhag ek ianch (2.5 seantimitar) hota hai. inhean netragolak kaha jata hai. netr kotariy guha shankvakar hoti hai. isake sabase gahare bhag mean ek gol chhidr (phoramen) hota hai, jisamean se hokar dvitiy kapaliy tantrika (aauptik tantrika) ka marg banata hai. netr ke oopar v niche do palakean hoti haian. ye netr ki dhool ke kanoan se suraksha karati haian. netr mean granthiyaan hoti haian. jinake dvara palak aur aankh sadaiv nam bani rahati haian. is guha ki chhat phrantal asthi se, pharsh maikzila se, letaral bhittiyaan kapolasthi tatha sphin aauid asthi se banati haian aur midiyal bhitti laikraimal, maikzila, itham aauil evan sphin aauid asthiyaan milakar banati haian. isi guha mean netragolak vasiy ootakoan mean ant:sthapit evan surakshit rahata hai.

aankh ki sanrachana

netr golak ki bhitti ka nirman ootakoan ki nimn tin paratoan se milakar hua hota hai-

1. bahm tantum parat
2. abhimadhy vahikamayi
3. antarik tantrikamayi parat

bahm tantum parat

yah aankh ki bahy, safed v aparadarshak parat hoti hai. isake ubhare hue bhag ko karniya kahate haian. is bhag mean bahar ki or ek bahut patali jhilli hoti hai. jise kanjanktaiva kahate haian. isake pichhale bhag se drishti tantrika nikalati hai. jisaka sambandh mastishk ki drik paliyoan se hota hai. bahy patal se hi netragolak ko ghumane vali peshiyaan sambandhit hoti haian.

netragolak mean yah sabase bahar ki sahara dene vali parat hai, jo mukhyatah dridh, tantumay sanyogi ootak ki moti membren se nirmit hoti hai. isamean shvet patal ya sklera evan svachchhamandal ya k aaurniya ka samavesh rahata hai.

• shvetapatal (sklera)

netragolak ke pichhale bhag ki aparadarshi, dridh tantu ootakoan ki shvet parat hoti hai. isase netragolak ka 5/6 pichhala bhag hi dhanka rahata hai. isaki bahy satah safed rahati hai aur aankh ka safed bhag banati hai, jis par aankh ko ghumane vali sabhi peshiyaan ju di rahati haian. yah netragolak ki aantarik komal paratoan ki raksha karati hai tatha usaki akriti ko sthir banae rakhati hai.

• svachchhamandal (k aaurniya)

bahy tantumayi parat ka agr paradarshi bhag hota hai, jo netragolak ke agr ubhare bhag par sthit rahata hai. k aaurniya netragolak ka samane vala 1/6 bhag banata hai. isamean raktavahikaoan ka poornataya abhav rahata hai. prakash kiranean k aaurniya se hokar retina par pahuanchati haian.

sklera evan k aaurniya nirantarata mean rahate haian. bahy tantumayi parat netragolak ko, pichhale bhag ko chho dakar jahaan sklera mean ek chhota-sa chhidr hota hai jisamean se hokar aauptik tantrika ke tantu netragolak se mastishk mean pahuanchate haian, poornataya dhanke rahati hai.

abhimadhy vahikamayi

yah sanyoji ootak ka bana patala star hota hai. isamean varnak koshikaean tatha rudhir koshikaoan ka jal paya jata hai. yah karniya se pichhe ek rangin gol parda banata hai. jise upatara ya airis kahate haian. isake madhy bhag mean ek chhidr hota hai jise tara kahate haian. yah bhag netr par p dane vale prakash ka niyaman karata hai. hai.

yah netragolak ki bich ki parat hoti hai, jisamean anekoan rakt vahikaean rahati haian. isamean ranjitapatal ya kor aauid, romak pind ya siliyari b aaudi tatha upatara ya airis ka samavesh hota hai.

is parat ka rang pigameantoan ke karan gahare rang ka hota hai jo aankh ke bhitari kaksh ko jisamean prakash ki kiranean retina par pratibimb banati haian, poornatah andhakaramay banane mean sahayak hoti haian. vahikamayi parat ka pichhala 2/3 bhag ek patali membren ka bana hota hai, jise ranjitapatal ya kor aauid kahate haian, sklera evan retina ke bich rakt vahikaoan evan sanyoji ootak ki parat hoti hai. yah (kor aauid) gahare-bhoore rang ka hota hai tatha retina ki rakt poorti karati hai.

vahikamayi parat age ki or ke bhag mean moti hokar siliyari b aaudi banati hai, jisamean peshiy evan granthil ootak rahate haian. siliyari peshiyaan leans ki akriti niyantrit karati haian tatha avashyakatanusar door ya samip ki prakash ki kiranoan ko kendrit karane mean sahayata karati haian. inhean samayojan ki peshiyaan kahate haian. siliyari granthiyaan pani jaisa drav stravit karati haian jise 'netrod' ya ekviyas hyoomar kahate hai, yah aankh mean leans tatha k aaurniya ke bich ke sthan mean bhara rahata hai tatha airis evan k aaurniya ke bich ke kon mean sthit chhote-chhote chhidroan ke madhyam se shiraoan mean jata hai.

kor aauid ka agr prasaran ek patali peshiy parat ke roop mean hota hai jise upatara ya airis kahate haian. yah netragolak ka rangin bhag hai jise k aaurniya se hokar dekha ja sakata hai. yah k aaurniya aur leans ke madhy sthit rahata hai tatha is sthan ko eantiriyal evan postiriyal chaimbars mean vibhajit karata hai. k aaurniya evan airis ke bich ka sthan eantiriyal chembar (agraj kaksh) tatha airis evan leans ke bich ka sthan postiriyal chaimbar (pashchaj kaksh) hota hai. airis mean vrittakar evan vikirn tantuoan ke roop mean peshiy ootak rahate haian, vattakar tantu putali ko sankuchit karate haian aur vikirn tantu ise vispharit (phailate) karate haian.

airis ke madhy mean ek golakar chhidr rahata hai. jise putali ya pyoopil kaha jata hai, isamean ap apane paravartit pratibimb ko ek chhoti-si d aaul ke saman dekhate haian. putali ka parinam prakash ki tivrata ke anusar ghatata-badhata rahata hai. tez roshani ko aankh mean pratisht hone se rokane ke lie tivr prakash ke prabhav se yah sankuchit ho jati hai tatha kam (mand) prakash mean vispharit yani phail jati hai taki adhik se adhik prakash (roshani) retina tak pahuanch sake. thumb|300px|left|aankh ki antarik sanrachana

antarik tantrikamayi parat

yah netr ki sabase andar ki mahattvapoorn parat hoti hai. isi par kisi bhi vastu ka pratibimb banata hai. drishti patal par drishti tantrika koshikaoan ka jal paya jata hai. drishti tantrika netr mean jis sthan se pratisht hoti hai, vahaan pratibimb nahian banata hai. is sthan ko andh bindu kahate haian. isi ke samip hi pit bindu paya jata hai, jis par vastu ka sarvadhik spasht pratibimb banata hai. drishti patal age ki or ek ubhayottal tal banata hai, jisake dvara prakash kiranean vastu se paravartit hokar aankh ke andar jati haian. tal ke donoan siroan par siliyari peshiyaan sthit hoti haian. inake dvara lens ka akar ghataya ya badhaya jata hai. is shakti ko netr ki sanmajan kshamata kahate haian. karniya tatha lens ke madhy jalakosh sthit hota hai, jisamean netrod drav tatha antahpatal aur lens ke madhy b da jelikosh paya jata hai, jisamean kachabh drav bhara rahata hai.

netragolak ke sabase bhitar ki parat ko drishtipatal ya retina kaha jata hai, jo tantrika koshikaoan evan tantrika koshikaoan evan tantrika tantuoan ki anekoan paratoan se bana hota hai aur netr ke postiriyal chaimbar mean avasthit hota hai. isake ek or kor aauid hai aur yah usase sata hua-sa rahata hai. doosari or netrakachabh drav bhara rahata hai. siliyari b aaudi ke thik pichhe isaka aant ho jata hai. yah andakar hota hai. retina mean ek moti evan ek patali parat hoti hai. moti parat tantrika ootak ki hoti hai jise nyoororetina kaha jata hai, yah aptik tantrika se jo dati hai. isake pichhe varnak yukt upakala ki ek patali parat hoti hai, jo kor aauid se sanlagn karati hai aur retina ke pichhe se riphlekshan ko rokati hai. nyoororetina mean lambi chh d ke akar ki koshikaean-r aauds evan shanku ke akar ki koshikaean-koans rahati haian jo apane bhitar vidyaman prakash sugrahi pigameantoan ke karan prakash ke prati ati sanvedanashil hote haian. inake atirikt nyoororetina mean bahut si any tantrikakoshikaean (nyooroans) bhi rahate haian. pratyek aankh mean lagabhag 125 miliyan r aauds evan 7 miliyan koans hoti haian, jinake kary alag-alag hote haian. adhikaansh koans retina ke madhy mean leans ke thik pichhe ke kshetr, jise pit bindu ya maikyoola lyootila kahate haian, mean avasthit rahate haian. maikyoola lyootila ke kendr mean ek chhota-sa gaddha rahata hai, ise gartika athava kendriy gartika ya phobiya seantrelis kahate haian, retina ke shesh bhag jise parisariy retina kahate haian mean r aauds evan kuchh koans avasthit rahate haian. maikyoola lyootiya retina ka vah sthan hai jahaan par sarvadhik spasht vimb banata hai. koans rang-bodh karate haian. jabaki r aauds kali-safed chhayaoan ka bodh karate hai, inake hi madhyam se ham kshin prakash mean bhi vastuoan ko dekh pate haian.

maikyoola lyootiya ke nam vale bhag ki or lagabhag 3 mili. ki doori par se aauptik tantrika netr golak se bahar nikalati hai, vah chhota-sa sthan drishti-chakrika ya aauptik disk kahalata hai aur chooanki yah prakash ke prati asanvedanashil hota hai isalie ise andh bindu par bimb n banane ka karan yah hai ki is sthan par r aauds evan koans ka poornatah abhav rahata haian.

rads evan koans drishti ke vastavik sangrahak aang hote haian tatha prakash jo un par pahuanchata hai, aveg utpann karata hai, jinaka sancharan aauptik tantrika ke dvara mastishk ke drishti kendr mean hota hai, jahaan r aauds evan koans drishti ke vastavik sangrahak aang hote haian. drishti-prabhav utpann hote haian.

netragolak ki guhaean

netragolak ko tin guhaoan mean vibhakt kiya gaya hai. k aaurniya evan airis ke bich ke kshetr ko agr kaksh ya eantiriyal chaimbar tatha airis evan leans ke bich ke kshetr ko pashch kaksh ya postiriyal chaimbar kaha jata hai. donoan kakshoan mean paradarshi, patala, jaliy taral bhara rahata hai jise netrod ya ekviyas hyoomar kahate haian netragolak ke bhitar ka dab ek-sa yani sthir banae rakhana isi ke oopar nirbhar karata hai. yah leans tatha k aaurniya ko avashyak poshak jaise aauksijan, glookoz evan amino-esids ki apoorti karata hai, jinamean poshan ke lie rakt vahikaean nahian hoti haian. netrod ka utpadan siliyari b aaudi ki keshikaoan dvara hota hai. yah postiriyar chaimbar se hokar gujarata hua eantiriyar chaimbar mean pahuanchata hai aur k aaurniya ke adhar par sthit skleral vinas sainas, jise shleman ki nalika bhi kahate hai, mean phail jata hai.

netragolak ki tisari aur sabase b di guha ko netrakachabh ya vitriyas chaimbar kaha jata hai, jo netragolak ke lagabhag 80% bhag mean hoti hai. yah leans ke pichhe ke sampoorn sthan ko bharati hai. is chaimbar mean rangahin paradarshi jaili ke saman padarth bhara hota hai jise netrakachabh drav ya vitriyas hyoomar kahate haian, jo vastav mean sanyoji ootak ka roopaantaran hota hai. isaka kary bahy dabav ke karan netragolak ko bahar nikalane se rokana hota hai. isamean kolejan evan hayalooronik esid ke atirikt any sanghatan netrod ke saman hi hote haian. netrakachabh drav ka utpadan siliyari b aaudi dvara hota hai. yah leans evan retina ke lie poshak ki apoorti karata hai.

leans

leans netragolak mean airis ke ekadam pichhe sthit rahata hai. yah paradarshi, dridh kiantu lachili, vrittakar dviuttal rachana hai, jisamean rakt vahikaean hoti haian. yah ek paradarshak, lachile kaipsool mean band rahata hai tatha sasapeansari ligameants dvara siliyari b aaudi se ju da hota hai. ye sasapeansari ligameants leans ko sthiti mean banaye rakhate haian aur inhian ke madhyam se siliyari peshiyaan leans par khianchav dalati haian aur door ya samip ki vastuoan ke dekhane ke liye leans ki akriti ko parivartit karati haian. sasapeansari ligameants ke shithilan se leans donoan or uth jata hai arthath leans ki uttalata badh jati hai tatha inake tanav se leans ki uttalata kam ho jati hai aur vah chapata-sa ho jata hai. aisi kriya vibhinn dooriyoan ki drishy vastuoan ke anusar svatah hoti hai, jise netroan ka samayojan kahate haian.

aankhoan ki sahayak sanrachanaean

thumb|400px|aankh ki antarik sanrachana aankhean atyant nazuk aang haian jo sahayak sanrachanaoan ke dvara surakshit rahati haian, ye rachanaean nimnalikhit haian-

• netraguha
• bhauanhe
• palakean
• netrashleshmala ya kॅnjanktaiva
• ashrupravahi upakaran
• netr peshiyaan

bhauanhe

phrantal asthi ke arbital pravardh ke oopar sthit tvacha par tirachhepan ke sath uge chhote, baloan ko bhauanhe kaha jata hai. inaka pramukh kary suraksha hai. ye mathe par ane vale pasine ko aankhoan mean ane se rokate haian tatha atyadhik dhoop se bachate haian.

palakean

ye pratyek aankh ke samane oopar evan niche patali tvacha se achchhadit avakashi ootak ki do gatishil tahean hoti haian. in donoan mean se oopar vali palakean adhik b di evan adhik gatishil rahati hai. oopar evan niche vali palakoan ke sangam sthal ko kaianthai kaha jata hai. nak ki or ke bhitar kaianthas ko midiyal kaianthas aur kan ki or ke bahari kaianthas ko letaral kaianthas kaha jata hai. palakoan ko char paratoan mean vibhikt kiya ja sakata hai.

1. tvachiy parat, jisamean barauniyaan hoti haian.
2. peshiy jisamean arbikulairis aaukyoolai peshi rahati hai jo palak ko aankh ke oopar girati hai.
3. tantumayi sanyoji ootak ki parat jisamean bahut-si tvagvasiy granthiyaan hoti haian, jo mibomiyan granthiyaan kahalati haian. inase sravit hone vala tailiy padarth donoan palakoan ko apas nean chipakane se bachata hai.
4. sabase andar ki parat ek patali gulabi membren se astarit hoti hai, jise kanajanktaiva kaha jata hai. palakean dhool evan any bahy vastuoan ke aankhoan mean pravesh rokane ke atirikt aankhoan mean atyadhik tivr prakash ko ekaek pravesh karane se rokati haian. palakoan ke pratyek kuchh sekandoan par jhapakate rahane se granthil strav (aansoo) netragolak par phail jate haian. jisase k aaurniya tar bani rahati hai. nidra ke dauran band palakean stravoan ke vashpikaran hone se rokati haian. jab koee vastu aankh ke pas ati hai, to prativarti kriya mean palakean svatah band ho jati haian.

barauniyaan

palakoan ke kinaroan par chhote-chhote mote bal age ki or nikalate rahate haian, jinhean barauni kaha jata hai. ye bahy padarthoan ko aankhoan mean pravesh karane se rokate haian. pratyek aankh ki palak mean lagabhag 200 barauniyaan hoti haian. pratyek barauni 3 se 5 mah mean svatah gir kar navin barauni ug ati hai. isake romakoopoan ke sankramit ho jane par guheriyaan nikal jati hai.

netrashleshmala ya kanajanktaiva

kanajanktaiva ek patali paradarshan myookas membren hai jo palakoan ke aantarik bhag ko astarit karati hai tatha palat kar netr golak ki oopar akar satah ko achchhadit karati hai. paradarshan k aaurniyaan par akar samapt ho jati hai, jo anachchhadit rahata hai. palak ko astarit karane vala bhag palpebral kanajanktaiva kahalata hai. in donoan bhagoan ke bich do netrashleshmakala kosh hote haian. inhian koshoan ke madhyam se netragolak evan palak mean gati hona sambhav hota hai. netr mean dali jane vali aeedr aaups prayah nichale palak ko pichhe ki or khianch kar adhovarti netrashleshmakala kosh mean dali jati haian.

ashrupravahi upakaran

pratyek aankh mean ek ashrupravahi upakaran ya laikraimal eparetas hota hai, jo ashrugranthi, ashrukosh, ashru vahiniyaan tatha nasa ashruvahini se banata hai.

ashrugranthiyaan

pratyek aankh ki oopari palak ke niche letaral kaianthas ke oopar sthit hoti haian. jinake srav se netragolak tar rahata hai. pratyek ashrugranthi badam ke akar ki hoti hai tatha phrantal asthi ke netraguha plet ke gart mean avasthit hoti hai. yah stravi upakala koshikaoan ki bani hoti hai. in granthiyoan mean se anek vahiniyaan nikalati haian jo netrashleshmalakosh ke oopari bhag mean khulati haian. in granthiyoan mean aansuoan ka nirman hota hai, jo ashruvahiniyoan dvara palakoan ke niche a jate haian aur netragolak ke samane vale bhag par phailane ke bad pratyek aankh ke midiyal kaianthas ki or jate haian jahaan par ye do ashrupravahi sookshmanalikaean yahaan sthit maans ke ek chhote-se lal ubhar jise maansaankur kahate haian, ke ek oopar aur ek niche se jati hai aur jo ashrukosh mean pravesh kar jati haian. ashrukosh nasaashruvahini ke hi oopar ka phaila hua vispharit bhag hota haian. nasa ashruvahini nasa guha ki asthit bhitti ko niche ki or par karati huee nak ki ianphiriyal mietas mean akar khulati hai, jisake dvara aansoo nak mean pahuanch jate haian.

aansoo

aankhean pratyek 2 se 10 sekand par jhapakati rahati haian, jisase ashrugranthi uddipt hokar ek nirjivanuk taral stravit karati hai, jise aansoo kahate haian. aansuoan mean jal, lavan, myoosin tatha ek jivanunashak eanjaim laisozaim rahata hai.

kary

1. aansoo aankhoan ko chikana evan nam rakhate haian, jisase palakoan ki gati sahajatapoorvak ho sake.
2. aansoo bahy vastuoan, dhoolakanoan adi ko dhokar saf kar dete haian.
3. aansoooan mean vidyaman jivanunashak eanjaim laisozaim mean jivanu nasht ho jate haian.
4. aansoo k aaurniya evan leans ko jal evan poshan ki apoorti karate haian.
5. aansoo netragolak ko svachchh, nam tatha chikani satah pradan karate haian.

netr peshiyaan

netragolak ki isake s aauket mean gati nimn 6 peshiyoan ke set dvara sampadit hoti hai. inamean char sidhi aur do tirachhi (tiryak) peshiyaan hoti haian. thumb|350px|left|aankh ki antarik sanrachana

sidhi peshiyaan

1. midiyal rektas
2. letaral rektas
3. supiriyar rektas
4. ianphiriyar rektas

tirachhi ya tiryak peshiyaan

1. supiriyar aaublik peshi
2. ianphiriyar aaublik peshi

ye sabhi peshiyaan bahy peshiyaan kahalati haian, kyoanki ye netragolak ke bahar rahati haian. pratyek peshi ka ek sira kapalasthi se sanlagn rahata hai. tatha doosara sira netragolak ke skalera se sanlagn rahata hai. in sabhi peshiyoan ki sahayata se netragolak ko sabhi dishaoan mean ghumana sanbhav hota hai. in peshiyoan ki gatiyoan mean samanvay hone se hi aankhean ghumayi jati haian. jisase donoan aankhean ek hi vastu par kendrit hoti haian. donoan aankhean sadaiv ek-doosare ke sahayog se kam karati haian aur yahi karan hai ki donoan aankhoan se dekhane par bhi ham keval ek hi vastu dekhate haian. peshiyoan ki kamazori ki avastha mean athava unake rogagrast ho jane par donoan aankhoan ki drishti ek hi sthan par nahian p dati hai, jisase vastu ek rahate hue bhi do dikhaee deti haian.

peshiyoan ki gatiyaan

uparyukt peshiyoan ki gatiyaan ek-doosare ke viparit hoti haian arthath jab peshiyoan ka ek set sankuchit hota hai to isake thik viparit vali peshiyoan ka seant shithilan ki kriya karata hai. jaise- supiriyar rektas ke sankuchan ke sath ianphiriyar rektas mean shithilan hota hai, jisase aankhean oopar uthati haian aur isake thik viparit jab ianphiriyar rektas sankuchit hoti hai, to supiriyar rektas mean shithilan hota hai, jisase aankhean niche ki or gati karati haian. isi prakar midiyal evan letaral rektas peshiyaan aankhoan oopar-niche aur bahar ki or gatiyaan karati haian. isake sath-sath ye aankhean ko chakravat ghumane mean bhi sahayata deti haian. aankhoan ke andar nimn tin chikani peshiyaan rahati haian. jinhean aantarasth peshiyaan kaha jata hai. siliyari peshi leans ke sasapeansari ligameant ke tanav ko kam karati hai tatha aankh ko sahi dhang se samayojit karane ke lie leans ko isaki akriti mean parivartan karane deti hai. sarakular peshi ya sphianktar pyoopila yah peshi putali ko charoan or vrittakar disha mean ghere rahati hai tatha putali ke kinaroan par rediyal disha mean sthit rahati hai tatha putali ko vispharit (phailati) karati hai.

palakoan ki peshiyaan

aaurbikuleris aaukyoolai peshi aankhoan ko band karane ke lie palakoan ko girati hai, tatha livetar palpebri supirioris peshi aankhoan ko kholane ke lie palakoan oopar uthati hai. supiriyar tarsal peshi, chikani peshi hoti hai, jisaki tantrika apoorti simpethetik tantrika tantr dvara hoti hai. yah oopar palak ko uthane mean sahayak hoti hai, isake pakshaghatagrast hone par oopari palak niche ko latak p dati hai.

drishti tantrika evan drishti path

aauptik ya drishti tantrikaean (dvitiy/II kapaliy tantrika) prakash sanved ki tantrikaean haian, jisake dvara dekhane ka kary hota hai. in tantrika tantuoan ki utpatti aankhoan ke retina mean hoti hai, jo maikyoola lyootiya se lagabhag 0.5 seanti mitar nak ki or abhibindu hokar (arthath ek bindu par milakar) tatha apas mean sanyojit hokar aauptik tantrika banate haian. yah tantrika netragolak ke pichhale bhag se nikalati hai aur pityootari granthi ke pas akar doosari or ki aauptik tantrika se mil jati hai. is kr aausiang haian. is sthan par akar donoan aankhoan ki aauptik tantrika ke nak ki or ke adhe-adhe tantu ek-doosare ko kr aaus kar sidhe age ki or badh jate haian. shesh (letaral said ke) pratyek retina ke tantrika tantu, bina ek-doosare ko kr aaus kie, donoan taraph (usi or) agrasar hote hue madhy mastishk mean pahuanch jate haian. aauptik chiyazma se hokar gujarane ke uparaant tantrika tantuoan ko drishtipath kaha jata hai. pratyek drishtipath mean doosari or ki aankh ke retina ke nasa tantuoan evan usi or ki aankh ki retina ke letaral tantuoan ka samavesh hota hai.

pratyek drishtipath seribram se hokar pichhe ki or jata hai tatha thailemas mean ke nyookliyas jinhean letaral jenikulet b aaudi kaha jata hai, ke sath tantumilan karata hai. vahaan se, letaral jenikulet b aaudi mean ke nyoor aauans ke aksh tantu pramastishkiy k aaurteks ke aauksipital lob mean prathamik drishtiparak k aaurteks mean prakshepit hote haian. jahaan drishti avegoan ki vyakhya evan vishleshan hota hai.

drishti ki kriya vidhi

thumb|350px|aankh ki antarik sanrachana prakash diptiman oorja ka ek roop hai, jo vayu ke madhyam se lagabhag 3,00,000 kilomitar prati sekand ki gati se tarangoan mean gaman karata hai.

prakash ki kiranean samanyatah samantar rekha mean chalati haian, kiantu jab ye ek ghanatv vale madhyam se bhinn ghanatv vale madhyam mean ko gujarati haian to ye jhuk jati haian, is jhukav ko aparvatan ya riphekshan kaha jata hai. bahy vayu se aankh mean pravesh karane vali prakash kiranean aparvit ho jati haian aur abhibindug hokar arthath ek bindu par milakar retina ke phokas bindu par kendrit ho jati hai.

retina par pahuanchane se poorv prakash ki kiranean aankhoan ke paradarshi apavartak madhyamoan- k aaurniya, ekviyas hyoomar, leans evan vitriyas hyoomar se hokar gujarati haian. inamean leans hi ek aisi rachana hai, jisamean prakash ki kiranoan ko jhukane ya apavartan karane ki kshamata rahati hai, jisase ve abhibindug hokar leans ke pichhe retina par bimb banati haian.

rachana ki drishti se aankhoan (netragolakoan) ki tulana kaimare se ki jati hai, jisamean palakean kaimare ke saman aankhoan ke lie shatar ka kam karati haian, prakash ke pravesh ke lie khi daki k aaurniya ke roop mean rahati hai. airis bhitar pravesh karane vale prakash ki matra ko niyantrit karata hai.

kristelain leans se prakash ki kiranean phokas hoti haian. abhimadhy vahikamayi parat kaimare ke prakasharodhak b aauks ka kam karati hai tatha retina kaimare ke saman prakash ke prati sanvedanashil plet ka kam karati haian.

kaimare ke samane jo vastu rahati hai, kaimare ki plet par usaka ulta pratibimb banata hai. thik usi prakar aankhoan se dekhi jane vali vastuoan ka ulta pratibimb retina par banata hai. vastu se prakash ki kiranean nikalati haian aur ekviyas hyoomar, leans evan vitriyas hyoomas ko par karake retina par p dati haian. leans tatha k aaurniya prakash ki samaantar kiranoan ko retina par kendribhoot karate haian. kaimare mean leans se phokas-bindu ki doori nishchit hoti hai aur leans ko age-pichhe khisaka kar photographi plet par vastu ka spasht pratibimb liya jata hai. aankh mean bhi leans tatha retina ki doori nishchit hoti hai. atah aankh mean leans se phokas- bindu ki doori ko siliyari peshiyoan ki sankuchan-kriya dvara badal kar vastu ke spasht pratibimb ko retina par prapt kiya jata hai.

aauptik tantrika dvara pratibimb ki vistrit soochana pramastishkiy k aaurteks ke aauksipital lob mean pahuanchati hai, jahaan yah chetana mean vikasit hoti hai. is prakar aauptik tantrikaoan dvara sanvedanaean mastishk ke drishti kshetr mean pahuanchati haian, phalatah mastishk ko dekhane ki anubhooti hoti hai. retina ke ulte bimb ko sidha dikhana mastishk ka kam hai.

samayojan

aankhoan mean pravesh karane vali sabhi samaantar prakash kiranoan ko retina par kendrit hone ke lie apavartit hone ya jhukane ki avashyakata hoti hai. 6 mitar (20 phit) se adhik door ki vastuoan ko dekhane ke lie unase ane vali prakash kiranoan ko adhik apavartan ki avashyakata nahian hoti hai parantu jaise-jaise vastu pas ati jati hai to use dekhane ke lie usase ane vali prakash kiranoan ko adhik apavartit hone ki avashyakata hoti hai.

door ki vastu se nikali prakash ki samaantar kiranean leans ke vartikal eksis par samakon par p dati haian. aankhean is prakar edajast hoti haian ki ye kiranean leans ke dvara jhuka di jati haian, jisase ve spasht bimb banane ke lie retina par phokas ho jati haian. pas (6 mitar se kam doori ki) ki vastu se nikali prakash ki kiranean apabinduk hoti haian tatha leans par tirachhe hokar p dati haian, jo samanyatah retina ke pichhe phokas hoti haian. ye kiranean retina par thik se phokas ho sakean isake lie leans ko mota, gol hona chahie. yah kriya siliyari peshiyoan ke dvara sanpadit hoti hai. sath hi bimb ki spashtata ke lie aankhoan mean pravesh hone vali kiranoan ki sankhyaoan mean, airis ke sankuchan se kami hoti haian. is prakar leans ke akar mean parivartan se tatha airis ke sankuchan se putali ke chhote hone ki kriya ko samayojan kahate haian. yah kriya pas ki vastu dekhate samay sadaiv hoti hai. vibhinn dooriyoan ke anusar leans ki motaee ya uttalata mean anuroop parivartan hone vali shakti ko hi anukoolan athava samayojan kahate hai. aankh ke leans ki phokas doori ki in svayan edajastiang kriyaoan ko aankh ki samayojan kshamata kahate haian. doshamukt aankhoan dvara 25 seantimitar. se door rakhi vastuoan ko hi spasht roop se dekha ja sakata hai. is doori ko 'spasht drishti' ki 'nyoonatam doori' kaha jata hai. jis adhikatam doori ke sthan tak aankhean vastuoan ko spasht roop mean dekh sakati hai, use aankhoan ka 'door bindu' kaha jata hai. jab koee vastu aankhoan ke bilkul samip rahati hai, to usaka donoan aankhoan ke retina par spasht phokas prapt karane ke lie aankhean svayan tho da bhitar ki or ghoomati haian. aankhoan ki yahi kriya 'anukoolan kahalati hai.

panne ki pragati avastha

adhar

prarambhik

madhyamik

poornata

shodh

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sanbandhit lekh

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