आँख  हिन्दी देवनागरी में पढ़ें।

(आंख se punarnirdeshit)
ankh vishay soochi
ankh evn usaki antarik snrachana

ankh (angrezi:Eye) adhikansh jiv jntuon ke sharir ka avashyak ang hain. is lekh men manav sharir se snbndhit ullekh hai. ankh ya netron ke dvara hamen vastu ka 'drishtigyan' hota hai. drishti vah snvedan hai, jis par manushy sarvadhik nirbhar karata hai. drishti ek jatil prakriya hai, jisamen prakash kiranon ke prati snvedita, svaroop, doori, rng adi sabhi ka pratyaksh gyan samahit hai. ankhen atynt jatil gyanendriyan hain, jo dayin-bayin donon or ek-ek netr kotariy guha men sthit rahati hai. ye lagabhag golakar hoti hain tatha inaka vyas lagabhag ek inch (2.5 sentimitar) hota hai. inhen netragolak kaha jata hai. netr kotariy guha shnkvakar hoti hai. isake sabase gahare bhag men ek gol chhidr (phoramen) hota hai, jisamen se hokar dvitiy kapaliy tantrika (aauptik tantrika) ka marg banata hai. netr ke oopar v niche do palaken hoti hain. ye netr ki dhool ke kanon se suraksha karati hain. netr men granthiyan hoti hain. jinake dvara palak aur ankh sadaiv nam bani rahati hain. is guha ki chhat phrantal asthi se, pharsh maikzila se, letaral bhittiyan kapolasthi tatha sphinaauid asthi se banati hain aur midiyal bhitti laikraimal, maikzila, ithamaauil evn sphinaauid asthiyan milakar banati hain. isi guha men netragolak vasiy ootakon men ant:sthapit evn surakshit rahata hai.

ankh ki snrachana

netr golak ki bhitti ka nirman ootakon ki nimn tin paraton se milakar hua hota hai-

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

bahm tantum parat

yah ankh ki bahy, safed v aparadarshak parat hoti hai. isake ubhare hue bhag ko karniya kahate hain. is bhag men bahar ki or ek bahut patali jhilli hoti hai. jise kanjnktaiva kahate hain. isake pichhale bhag se drishti tantrika nikalati hai. jisaka sambandh mastishk ki drik paliyon se hota hai. bahy patal se hi netragolak ko ghumane vali peshiyan sambandhit hoti hain.

netragolak men yah sabase bahar ki sahara dene vali parat hai, jo mukhyatah dridh, tntumay snyogi ootak ki moti membren se nirmit hoti hai. isamen shvet patal ya sklera evn svachchhamandal ya kaaurniya ka samavesh rahata hai.

  • shvetapatal (sklera)

netragolak ke pichhale bhag ki aparadarshi, dridh tntu ootakon ki shvet parat hoti hai. isase netragolak ka 5/6 pichhala bhag hi dhnka rahata hai. isaki bahy satah safed rahati hai aur ankh ka safed bhag banati hai, jis par ankh ko ghumane vali sabhi peshiyan judi rahati hain. yah netragolak ki antarik komal paraton ki raksha karati hai tatha usaki akriti ko sthir banae rakhati hai.

  • svachchhamandal (kaaurniya)

bahy tntumayi parat ka agr paradarshi bhag hota hai, jo netragolak ke agr ubhare bhag par sthit rahata hai. kaaurniya netragolak ka samane vala 1/6 bhag banata hai. isamen raktavahikaon ka poornataya abhav rahata hai. prakash kiranen kaaurniya se hokar retina par pahunchati hain.

sklera evn kaaurniya nirntarata men rahate hain. bahy tntumayi parat netragolak ko, pichhale bhag ko chhodakar jahan sklera men ek chhota-sa chhidr hota hai jisamen se hokar aauptik tantrika ke tntu netragolak se mastishk men pahunchate hain, poornataya dhnke rahati hai.

abhimadhy vahikamayi

yah snyoji ootak ka bana patala star hota hai. isamen varnak koshikaen tatha rudhir koshikaon ka jal paya jata hai. yah karniya se pichhe ek rngin gol parda banata hai. jise upatara ya airis kahate hain. isake madhy bhag men ek chhidr hota hai jise tara kahate hain. yah bhag netr par padane vale prakash ka niyaman karata hai. hai.

yah netragolak ki bich ki parat hoti hai, jisamen anekon rakt vahikaen rahati hain. isamen rnjitapatal ya koraauid, romak pind ya siliyari baaudi tatha upatara ya airis ka samavesh hota hai.

is parat ka rng pigamenton ke karan gahare rng ka hota hai jo ankh ke bhitari kaksh ko jisamen prakash ki kiranen retina par pratibimb banati hain, poornatah andhakaramay banane men sahayak hoti hain. vahikamayi parat ka pichhala 2/3 bhag ek patali membren ka bana hota hai, jise rnjitapatal ya koraauid kahate hain, sklera evn retina ke bich rakt vahikaon evn snyoji ootak ki parat hoti hai. yah (koraauid) gahare-bhoore rng ka hota hai tatha retina ki rakt poorti karati hai.

vahikamayi parat age ki or ke bhag men moti hokar siliyari baaudi banati hai, jisamen peshiy evn grnthil ootak rahate hain. siliyari peshiyan lens ki akriti niyntrit karati hain tatha avashyakatanusar door ya samip ki prakash ki kiranon ko kendrit karane men sahayata karati hain. inhen samayojan ki peshiyan kahate hain. siliyari grnthiyan pani jaisa drav stravit karati hain jise 'netrod' ya ekviyas hyoomar kahate hai, yah ankh men lens tatha kaaurniya ke bich ke sthan men bhara rahata hai tatha airis evn kaaurniya ke bich ke kon men sthit chhote-chhote chhidron ke madhyam se shiraon men jata hai.

koraauid ka agr prasaran ek patali peshiy parat ke roop men hota hai jise upatara ya airis kahate hain. yah netragolak ka rngin bhag hai jise kaaurniya se hokar dekha ja sakata hai. yah kaaurniya aur lens ke madhy sthit rahata hai tatha is sthan ko entiriyal evn postiriyal chaimbars men vibhajit karata hai. kaaurniya evn airis ke bich ka sthan entiriyal chembar (agraj kaksh) tatha airis evn lens ke bich ka sthan postiriyal chaimbar (pashchaj kaksh) hota hai. airis men vrittakar evn vikirn tntuon ke roop men peshiy ootak rahate hain, vattakar tntu putali ko snkuchit karate hain aur vikirn tntu ise vispharit (phailate) karate hain.

airis ke madhy men ek golakar chhidr rahata hai. jise putali ya pyoopil kaha jata hai, isamen ap apane paravartit pratibimb ko ek chhoti-si daaul ke saman dekhate hain. putali ka parinam prakash ki tivrata ke anusar ghatata-badhata rahata hai. tez roshani ko ankh men pratisht hone se rokane ke lie tivr prakash ke prabhav se yah snkuchit ho jati hai tatha kam (mand) prakash men vispharit yani phail jati hai taki adhik se adhik prakash (roshani) retina tak pahunch sake.

ankh ki antarik snrachana

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 koshikaon ka jal paya jata hai. drishti tantrika netr men jis sthan se pratisht hoti hai, vahan pratibimb nahin banata hai. is sthan ko andh bindu kahate hain. 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 kiranen vastu se paravartit hokar ankh ke andar jati hain. tal ke donon siron par siliyari peshiyan sthit hoti hain. inake dvara lens ka akar ghataya ya badhaya jata hai. is shakti ko netr ki snmajan kshamata kahate hain. karniya tatha lens ke madhy jalakosh sthit hota hai, jisamen netrod drav tatha antahpatal aur lens ke madhy bada jelikosh paya jata hai, jisamen kachabh drav bhara rahata hai.

netragolak ke sabase bhitar ki parat ko drishtipatal ya retina kaha jata hai, jo tantrika koshikaon evn tantrika koshikaon evn tantrika tntuon ki anekon paraton se bana hota hai aur netr ke postiriyal chaimbar men avasthit hota hai. isake ek or koraauid hai aur yah usase sata hua-sa rahata hai. doosari or netrakachabh drav bhara rahata hai. siliyari baaudi ke thik pichhe isaka ant ho jata hai. yah andakar hota hai. retina men ek moti evn ek patali parat hoti hai. moti parat tantrika ootak ki hoti hai jise nyoororetina kaha jata hai, yah aptik tantrika se jodati hai. isake pichhe varnak yukt upakala ki ek patali parat hoti hai, jo koraauid se snlagn karati hai aur retina ke pichhe se riphlekshan ko rokati hai. nyoororetina men lambi chhad ke akar ki koshikaen-raauds evn shnku ke akar ki koshikaen-kons rahati hain jo apane bhitar vidyaman prakash sugrahi pigamenton ke karan prakash ke prati ati snvedanashil hote hain. inake atirikt nyoororetina men bahut si any tantrikakoshikaen (nyoorons) bhi rahate hain. pratyek ankh men lagabhag 125 miliyan raauds evn 7 miliyan kons hoti hain, jinake kary alag-alag hote hain. adhikansh kons retina ke madhy men lens ke thik pichhe ke kshetr, jise pit bindu ya maikyoola lyootila kahate hain, men avasthit rahate hain. maikyoola lyootila ke kendr men ek chhota-sa gaddha rahata hai, ise gartika athava kendriy gartika ya phobiya sentrelis kahate hain, retina ke shesh bhag jise parisariy retina kahate hain men raauds evn kuchh kons avasthit rahate hain. maikyoola lyootiya retina ka vah sthan hai jahan par sarvadhik spasht vimb banata hai. kons rng-bodh karate hain. jabaki raauds kali-safed chhayaon ka bodh karate hai, inake hi madhyam se ham kshin prakash men bhi vastuon ko dekh pate hain.

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 choonki yah prakash ke prati asnvedanashil hota hai isalie ise andh bindu par bimb n banane ka karan yah hai ki is sthan par raauds evn kons ka poornatah abhav rahata hain.

rads evn kons drishti ke vastavik sngrahak ang hote hain tatha prakash jo un par pahunchata hai, aveg utpann karata hai, jinaka sncharan aauptik tantrika ke dvara mastishk ke drishti kendr men hota hai, jahan raauds evn kons drishti ke vastavik sngrahak ang hote hain. drishti-prabhav utpann hote hain.

netragolak ki guhaen

netragolak ko tin guhaon men vibhakt kiya gaya hai. kaaurniya evn airis ke bich ke kshetr ko agr kaksh ya entiriyal chaimbar tatha airis evn lens ke bich ke kshetr ko pashch kaksh ya postiriyal chaimbar kaha jata hai. donon kakshon men paradarshi, patala, jaliy taral bhara rahata hai jise netrod ya ekviyas hyoomar kahate hain netragolak ke bhitar ka dab ek-sa yani sthir banae rakhana isi ke oopar nirbhar karata hai. yah lens tatha kaaurniya ko avashyak poshak jaise aauksijan, glookoz evn amino-esids ki apoorti karata hai, jinamen poshan ke lie rakt vahikaen nahin hoti hain. netrod ka utpadan siliyari baaudi ki keshikaon dvara hota hai. yah postiriyar chaimbar se hokar gujarata hua entiriyar chaimbar men pahunchata hai aur kaaurniya ke adhar par sthit skleral vinas sainas, jise shleman ki nalika bhi kahate hai, men phail jata hai.

netragolak ki tisari aur sabase badi guha ko netrakachabh ya vitriyas chaimbar kaha jata hai, jo netragolak ke lagabhag 80% bhag men hoti hai. yah lens ke pichhe ke sampoorn sthan ko bharati hai. is chaimbar men rngahin paradarshi jaili ke saman padarth bhara hota hai jise netrakachabh drav ya vitriyas hyoomar kahate hain, jo vastav men snyoji ootak ka roopantaran hota hai. isaka kary bahy dabav ke karan netragolak ko bahar nikalane se rokana hota hai. isamen kolejan evn hayalooronik esid ke atirikt any snghatan netrod ke saman hi hote hain. netrakachabh drav ka utpadan siliyari baaudi dvara hota hai. yah lens evn retina ke lie poshak ki apoorti karata hai.

lens

lens netragolak men airis ke ekadam pichhe sthit rahata hai. yah paradarshi, dridh kintu lachili, vrittakar dviuttal rachana hai, jisamen rakt vahikaen hoti hain. yah ek paradarshak, lachile kaipsool men band rahata hai tatha sasapensari ligaments dvara siliyari baaudi se juda hota hai. ye sasapensari ligaments lens ko sthiti men banaye rakhate hain aur inhin ke madhyam se siliyari peshiyan lens par khinchav dalati hain aur door ya samip ki vastuon ke dekhane ke liye lens ki akriti ko parivartit karati hain. sasapensari ligaments ke shithilan se lens donon or uth jata hai arthath lens ki uttalata badh jati hai tatha inake tanav se lens ki uttalata kam ho jati hai aur vah chapata-sa ho jata hai. aisi kriya vibhinn dooriyon ki drishy vastuon ke anusar svatah hoti hai, jise netron ka samayojan kahate hain.

ankhon ki sahayak snrachanaen

ankh ki antarik snrachana

ankhen atynt nazuk ang hain jo sahayak snrachanaon ke dvara surakshit rahati hain, ye rachanaen nimnalikhit hain-

  • netraguha
  • bhaunhe
  • palaken
  • netrashleshmala ya kanjnktaiva
  • ashrupravahi upakaran
  • netr peshiyan

bhaunhe

phrntal asthi ke arbital pravardh ke oopar sthit tvacha par tirachhepan ke sath uge chhote, balon ko bhaunhe kaha jata hai. inaka pramukh kary suraksha hai. ye mathe par ane vale pasine ko ankhon men ane se rokate hain tatha atyadhik dhoop se bachate hain.

palaken

ye pratyek ankh ke samane oopar evn niche patali tvacha se achchhadit avakashi ootak ki do gatishil tahen hoti hain. in donon men se oopar vali palaken adhik badi evn adhik gatishil rahati hai. oopar evn niche vali palakon ke sngam sthal ko kainthai kaha jata hai. nak ki or ke bhitar kainthas ko midiyal kainthas aur kan ki or ke bahari kainthas ko letaral kainthas kaha jata hai. palakon ko char paraton men vibhikt kiya ja sakata hai.

  1. tvachiy parat, jisamen barauniyan hoti hain.
  2. peshiy jisamen arbikulairis aaukyoolai peshi rahati hai jo palak ko ankh ke oopar girati hai.
  3. tntumayi snyoji ootak ki parat jisamen bahut-si tvagvasiy grnthiyan hoti hain, jo mibomiyan grnthiyan kahalati hain. inase sravit hone vala tailiy padarth donon palakon ko apas nen chipakane se bachata hai.
  4. sabase andar ki parat ek patali gulabi membren se astarit hoti hai, jise kanajnktaiva kaha jata hai. palaken dhool evn any bahy vastuon ke ankhon men pravesh rokane ke atirikt ankhon men atyadhik tivr prakash ko ekaek pravesh karane se rokati hain. palakon ke pratyek kuchh sekandon par jhapakate rahane se grnthil strav (ansoo) netragolak par phail jate hain. jisase kaaurniya tar bani rahati hai. nidra ke dauran band palaken stravon ke vashpikaran hone se rokati hain. jab koee vastu ankh ke pas ati hai, to prativarti kriya men palaken svatah band ho jati hain.

barauniyan

palakon ke kinaron par chhote-chhote mote bal age ki or nikalate rahate hain, jinhen barauni kaha jata hai. ye bahy padarthon ko ankhon men pravesh karane se rokate hain. pratyek ankh ki palak men lagabhag 200 barauniyan hoti hain. pratyek barauni 3 se 5 mah men svatah gir kar navin barauni ug ati hai. isake romakoopon ke snkramit ho jane par guheriyan nikal jati hai.

netrashleshmala ya kanajnktaiva

kanajnktaiva ek patali paradarshan myookas membren hai jo palakon ke antarik bhag ko astarit karati hai tatha palat kar netr golak ki oopar akar satah ko achchhadit karati hai. paradarshan kaaurniyan par akar samapt ho jati hai, jo anachchhadit rahata hai. palak ko astarit karane vala bhag palpebral kanajnktaiva kahalata hai. in donon bhagon ke bich do netrashleshmakala kosh hote hain. inhin koshon ke madhyam se netragolak evn palak men gati hona sambhav hota hai. netr men dali jane vali aeedraaups prayah nichale palak ko pichhe ki or khinch kar adhovarti netrashleshmakala kosh men dali jati hain.

ashrupravahi upakaran

pratyek ankh men ek ashrupravahi upakaran ya laikraimal eparetas hota hai, jo ashrugrnthi, ashrukosh, ashru vahiniyan tatha nasa ashruvahini se banata hai.

ashrugrnthiyan

pratyek ankh ki oopari palak ke niche letaral kainthas ke oopar sthit hoti hain. jinake srav se netragolak tar rahata hai. pratyek ashrugrnthi badam ke akar ki hoti hai tatha phrntal asthi ke netraguha plet ke gart men avasthit hoti hai. yah stravi upakala koshikaon ki bani hoti hai. in grnthiyon men se anek vahiniyan nikalati hain jo netrashleshmalakosh ke oopari bhag men khulati hain. in grnthiyon men ansuon ka nirman hota hai, jo ashruvahiniyon dvara palakon ke niche a jate hain aur netragolak ke samane vale bhag par phailane ke bad pratyek ankh ke midiyal kainthas ki or jate hain jahan par ye do ashrupravahi sookshmanalikaen yahan sthit mans ke ek chhote-se lal ubhar jise mansankur kahate hain, ke ek oopar aur ek niche se jati hai aur jo ashrukosh men pravesh kar jati hain. ashrukosh nasaashruvahini ke hi oopar ka phaila hua vispharit bhag hota hain. nasa ashruvahini nasa guha ki asthit bhitti ko niche ki or par karati huee nak ki inphiriyal mietas men akar khulati hai, jisake dvara ansoo nak men pahunch jate hain.

ansoo

ankhen pratyek 2 se 10 sekand par jhapakati rahati hain, jisase ashrugrnthi uddipt hokar ek nirjivanuk taral stravit karati hai, jise ansoo kahate hain. ansuon men jal, lavan, myoosin tatha ek jivanunashak enjaim laisozaim rahata hai.

kary
  1. ansoo ankhon ko chikana evn nam rakhate hain, jisase palakon ki gati sahajatapoorvak ho sake.
  2. ansoo bahy vastuon, dhoolakanon adi ko dhokar saf kar dete hain.
  3. ansooon men vidyaman jivanunashak enjaim laisozaim men jivanu nasht ho jate hain.
  4. ansoo kaaurniya evn lens ko jal evn poshan ki apoorti karate hain.
  5. ansoo netragolak ko svachchh, nam tatha chikani satah pradan karate hain.

netr peshiyan

netragolak ki isake saauket men gati nimn 6 peshiyon ke set dvara sampadit hoti hai. inamen char sidhi aur do tirachhi (tiryak) peshiyan hoti hain.

ankh ki antarik snrachana

sidhi peshiyan

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

tirachhi ya tiryak peshiyan

  1. supiriyar aaublik peshi
  2. inphiriyar aaublik peshi

ye sabhi peshiyan bahy peshiyan kahalati hain, kyonki ye netragolak ke bahar rahati hain. pratyek peshi ka ek sira kapalasthi se snlagn rahata hai. tatha doosara sira netragolak ke skalera se snlagn rahata hai. in sabhi peshiyon ki sahayata se netragolak ko sabhi dishaon men ghumana snbhav hota hai. in peshiyon ki gatiyon men samnvay hone se hi ankhen ghumayi jati hain. jisase donon ankhen ek hi vastu par kendrit hoti hain. donon ankhen sadaiv ek-doosare ke sahayog se kam karati hain aur yahi karan hai ki donon ankhon se dekhane par bhi ham keval ek hi vastu dekhate hain. peshiyon ki kamazori ki avastha men athava unake rogagrast ho jane par donon ankhon ki drishti ek hi sthan par nahin padati hai, jisase vastu ek rahate hue bhi do dikhaee deti hain.

peshiyon ki gatiyan

uparyukt peshiyon ki gatiyan ek-doosare ke viparit hoti hain arthath jab peshiyon ka ek set snkuchit hota hai to isake thik viparit vali peshiyon ka sent shithilan ki kriya karata hai. jaise- supiriyar rektas ke snkuchan ke sath inphiriyar rektas men shithilan hota hai, jisase ankhen oopar uthati hain aur isake thik viparit jab inphiriyar rektas snkuchit hoti hai, to supiriyar rektas men shithilan hota hai, jisase ankhen niche ki or gati karati hain. isi prakar midiyal evn letaral rektas peshiyan ankhon oopar-niche aur bahar ki or gatiyan karati hain. isake sath-sath ye ankhen ko chakravat ghumane men bhi sahayata deti hain. ankhon ke andar nimn tin chikani peshiyan rahati hain. jinhen antarasth peshiyan kaha jata hai. siliyari peshi lens ke sasapensari ligament ke tanav ko kam karati hai tatha ankh ko sahi dhng se samayojit karane ke lie lens ko isaki akriti men parivartan karane deti hai. sarakular peshi ya sphinktar pyoopila yah peshi putali ko charon or vrittakar disha men ghere rahati hai tatha putali ke kinaron par rediyal disha men sthit rahati hai tatha putali ko vispharit (phailati) karati hai.

palakon ki peshiyan

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

drishti tantrika evn drishti path

aauptik ya drishti tantrikaen (dvitiy/II kapaliy tantrika) prakash snved ki tantrikaen hain, jisake dvara dekhane ka kary hota hai. in tantrika tntuon ki utpatti ankhon ke retina men hoti hai, jo maikyoola lyootiya se lagabhag 0.5 senti mitar nak ki or abhibindu hokar (arthath ek bindu par milakar) tatha apas men snyojit hokar aauptik tantrika banate hain. yah tantrika netragolak ke pichhale bhag se nikalati hai aur pityootari grnthi ke pas akar doosari or ki aauptik tantrika se mil jati hai. is kraausing hain. is sthan par akar donon ankhon ki aauptik tantrika ke nak ki or ke adhe-adhe tntu ek-doosare ko kraaus kar sidhe age ki or badh jate hain. shesh (letaral said ke) pratyek retina ke tantrika tntu, bina ek-doosare ko kraaus kie, donon taraph (usi or) agrasar hote hue madhy mastishk men pahunch jate hain. aauptik chiyazma se hokar gujarane ke uparant tantrika tntuon ko drishtipath kaha jata hai. pratyek drishtipath men doosari or ki ankh ke retina ke nasa tntuon evn usi or ki ankh ki retina ke letaral tntuon ka samavesh hota hai.

pratyek drishtipath seribram se hokar pichhe ki or jata hai tatha thailemas men ke nyookliyas jinhen letaral jenikulet baaudi kaha jata hai, ke sath tntumilan karata hai. vahan se, letaral jenikulet baaudi men ke nyooraauns ke aksh tntu pramastishkiy kaaurteks ke aauksipital lob men prathamik drishtiparak kaaurteks men prakshepit hote hain. jahan drishti avegon ki vyakhya evn vishleshan hota hai.

drishti ki kriya vidhi

ankh ki antarik snrachana

prakash diptiman oorja ka ek roop hai, jo vayu ke madhyam se lagabhag 3,00,000 kilomitar prati sekand ki gati se tarngon men gaman karata hai.

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

retina par pahunchane se poorv prakash ki kiranen ankhon ke paradarshi apavartak madhyamon- kaaurniya, ekviyas hyoomar, lens evn vitriyas hyoomar se hokar gujarati hain. inamen lens hi ek aisi rachana hai, jisamen prakash ki kiranon ko jhukane ya apavartan karane ki kshamata rahati hai, jisase ve abhibindug hokar lens ke pichhe retina par bimb banati hain.

rachana ki drishti se ankhon (netragolakon) ki tulana kaimare se ki jati hai, jisamen palaken kaimare ke saman ankhon ke lie shatar ka kam karati hain, prakash ke pravesh ke lie khidaki kaaurniya ke roop men rahati hai. airis bhitar pravesh karane vale prakash ki matra ko niyntrit karata hai.

kristelain lens se prakash ki kiranen phokas hoti hain. abhimadhy vahikamayi parat kaimare ke prakasharodhak baauks ka kam karati hai tatha retina kaimare ke saman prakash ke prati snvedanashil plet ka kam karati hain.

kaimare ke samane jo vastu rahati hai, kaimare ki plet par usaka ulta pratibimb banata hai. thik usi prakar ankhon se dekhi jane vali vastuon ka ulta pratibimb retina par banata hai. vastu se prakash ki kiranen nikalati hain aur ekviyas hyoomar, lens evn vitriyas hyoomas ko par karake retina par padati hain. lens tatha kaaurniya prakash ki samantar kiranon ko retina par kendribhoot karate hain. kaimare men lens se phokas-bindu ki doori nishchit hoti hai aur lens ko age-pichhe khisaka kar photographi plet par vastu ka spasht pratibimb liya jata hai. ankh men bhi lens tatha retina ki doori nishchit hoti hai. atah ankh men lens se phokas- bindu ki doori ko siliyari peshiyon ki snkuchan-kriya dvara badal kar vastu ke spasht pratibimb ko retina par prapt kiya jata hai.

aauptik tantrika dvara pratibimb ki vistrit soochana pramastishkiy kaaurteks ke aauksipital lob men pahunchati hai, jahan yah chetana men vikasit hoti hai. is prakar aauptik tantrikaon dvara snvedanaen mastishk ke drishti kshetr men pahunchati hain, phalatah mastishk ko dekhane ki anubhooti hoti hai. retina ke ulte bimb ko sidha dikhana mastishk ka kam hai.

samayojan

ankhon men pravesh karane vali sabhi samantar prakash kiranon ko retina par kendrit hone ke lie apavartit hone ya jhukane ki avashyakata hoti hai. 6 mitar (20 phit) se adhik door ki vastuon ko dekhane ke lie unase ane vali prakash kiranon ko adhik apavartan ki avashyakata nahin hoti hai parntu jaise-jaise vastu pas ati jati hai to use dekhane ke lie usase ane vali prakash kiranon ko adhik apavartit hone ki avashyakata hoti hai.

door ki vastu se nikali prakash ki samantar kiranen lens ke vartikal eksis par samakon par padati hain. ankhen is prakar edajast hoti hain ki ye kiranen lens ke dvara jhuka di jati hain, jisase ve spasht bimb banane ke lie retina par phokas ho jati hain. pas (6 mitar se kam doori ki) ki vastu se nikali prakash ki kiranen apabinduk hoti hain tatha lens par tirachhe hokar padati hain, jo samanyatah retina ke pichhe phokas hoti hain. ye kiranen retina par thik se phokas ho saken isake lie lens ko mota, gol hona chahie. yah kriya siliyari peshiyon ke dvara snpadit hoti hai. sath hi bimb ki spashtata ke lie ankhon men pravesh hone vali kiranon ki snkhyaon men, airis ke snkuchan se kami hoti hain. is prakar lens ke akar men parivartan se tatha airis ke snkuchan se putali ke chhote hone ki kriya ko samayojan kahate hain. yah kriya pas ki vastu dekhate samay sadaiv hoti hai. vibhinn dooriyon ke anusar lens ki motaee ya uttalata men anuroop parivartan hone vali shakti ko hi anukoolan athava samayojan kahate hai. ankh ke lens ki phokas doori ki in svayn edajasting kriyaon ko ankh ki samayojan kshamata kahate hain. doshamukt ankhon dvara 25 sentimitar. se door rakhi vastuon 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 ankhen vastuon ko spasht roop men dekh sakati hai, use ankhon ka 'door bindu' kaha jata hai. jab koee vastu ankhon ke bilkul samip rahati hai, to usaka donon ankhon ke retina par spasht phokas prapt karane ke lie ankhen svayn thoda bhitar ki or ghoomati hain. ankhon ki yahi kriya 'anukoolan kahalati hai.


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tika tippani aur sndarbh

snbndhit lekh

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