I vision chu eng nge ni? Chipchiar takin sawi ila!

Khawvel hi engtin nge i hmuh? Engtin nge i chhehvela thil awmte, mipui, rawng mawi tak tak, heng zawng zawng hi i hriat chian? Hei hi a chhan ber chu kan mit hlu tak tak leh thluak hian thil mak tak a ti dun a, chu chu "Vision" an ti a ni . Hei hi hmuh mai ni lovin thil buaithlak zawk leh pawimawh zawk a ni. Chuvangin vawiinah hian he vision hi a awlsam zawngin, i hriatthiam theih dan tur angin kan sawi dawn a ni.

Inlarna chu eng nge ni? A awlsam zawngin...

A awlsam zawngin, vision chu i mit leh thluak thawhhona hmanga i chhehvel thil atanga êng lo chhuak hmanga thlalak siamna a ni. Kan hriatna bulpui panga zinga pakhat a ni. Mi tam zawk chuan inlarna hmangin khawvel hi an hrethiam a. Chumi tel lo chuan kan nun a danglam dâwn êm êm tih han ngaihtuah teh!

Engtin nge kan mit hian hna a thawh? Mechanism mak tak mai a ni!

I mitin êng a hriatchhuah a, nerve signal-a a chantir atang hian hmuh theihna process hi a intan a ni. Chumi hnuah chuan heng signal te hi i mit nerve kaltlangin i thluak thlengin an kal a ni. Thluak hian heng signal te hi a dawng a, a hrilhfiah a, i hmuh image chu a siam chhuak thin. Hei hi a thleng rang hle a, second khatah vawi engemaw zat a thleng thin.

Mit hi camera ang mai a ni em?

Ni e, kan mit hi camera nen kan tehkhin fo thin. Mahse a takah chuan a lehlam a ni. Camera hi mihring mit ang chiaha siam technology a ni. Ngaihtuah teh, camera pakhat hian lens a nei a. Hei hian light a khawlkhawm a, camera chhunga sensor bik pakhatah a hruai a ni. Chu sensor chuan êng chu electrical signal-ah a chantir a ni. Tichuan, camera chhunga computer te tak te chuan chu signal chu a process a, image-ah a chang ta a ni. Camera focus i siamrem thei a, light engzat nge luh phal tih i control thei a, i mit hian lens a nei bawk . Chungte chuan êng an khawlkhawm a, mit chhunga retina -ah an hruai a ni. He retina hi chu camera chhunga sensor ang mai a ni a, mahse a hmasawn zawkin a buaithlak zawk hle. Retina-a êng tla chu nerve signal-ah a inthlak a, thluak lamah a thawn chhuak a ni. Chu camera te theihna bik, `focusing` leh light control te chu i mit hian automatic in a ti vek a ni. I mit chhunga ring dum ( the pupil ) chu a dilate emaw, a constrict emaw a, chu chuan mit chhunga êng lut zat a control a ni. Tin, mit chhunga thau (muscle) te hian lens pianzia an thlak danglam a, `focus` a siam a, chutiang chuan thil hlat zawng hrang hrangah chiang takin i hmu thei a ni.

Retina hi eng nge ni? Chutah chuan eng thil nge thleng?

I retina hi cell chi khat bik, sensitive tak a ni. Heng photoreceptor te hi kan ti a, chu chu "êng dawngtu cell" tihna a ni. Heng cell-te chunga êng a tlak chuan an chhungah chemical leh electrical reaction a thleng a ni. Chutiang chuan heng cell te hian light chu nerve signal ah an encode thin. Photoreceptor hi chi hnih a awm a, chungte chu:

• Rod cell (`Rods`) te chu:Hengte hian light intensity inthlak danglamna an hmuchhuak ber. Heng cell te hi hmun thim leh êng tlem zawka thil hmuh theihna tura puitu an ni.
• Cones: Heng cell te hi an sensitive zawk. Thil chipchiar tak tak an hmu thei a, rawng hrang hrang an thliar hrang thei bawk.

He light hi nerve signal-ah a chantir hnuah retina chuan chu signal chu i optic nerve-ah a thawn chhuak thin.

Optic Nerves te chanvo

I optic nerve te hi data cable ang mai a ni. Retina atanga thluak hmun hrang hrangah signal an phur a. Heng signal te hi optic nerve kaltlangin an kal a, thluak chhunga signal te decode leh hriatthiamna mawhphurtu te an thleng thin.

Thutlukna hnuhnung ber chu thluak hian a siam a ni!

Step hnuhnung ber leh pawimawh ber chu i thluak chhungah a thleng thin. Thluak hian optic nerve kaltlangin encoded signal lo lutte chu a dawng a, chu chu a decode a, chu information chu hmangin mit tin hmuh tur "image" a siam ta a ni.

Ngaihtuah teh, he sentence hi i chhiar hian i thluak hmun hrang hrang, tawng hriatthiamna leh hriatrengna hriatrengna atana puitu che pawh hi a inrawlh ve tho a ni. Chutiang chuan heng thute hi i hrethiam thei a, a awmzia i hre reng thei a, a kaihhnawih hriatrengnate chu i hrechhuak thei bawk.

Chumi awmzia chu, i thil hmuh dan azirin, thluak hmun hrang hrangte chuan chu lem chu a taka hrethiam turin an thawk ho tihna a ni.

Eng natna nge mit hmuhna tichhe thei?

Hmuh theihna hian taksa peng leh insiam hrang hrang engemaw zat thawhhona a neih avangin natna chi hrang hrangin he kalphung hi a tibuai thei a ni. Thil awm dan thenkhat chuan mit hmuhna (visual system) hmun khat aia tam a nghawng thei. Mit hmuhna tichhe thei natna chi hrang hrang hetiang hi a ni:

• Mit natna : Entirnan, mit natna leh mit natna (glaucoma) .
• Retina leh optic nerves nena inzawm natna: Diabetic retinopathy ang chi natna.
• Thluak kaihhnawih natna: Stroke emaw thluaka tumor chi hrang hrang hian mit hmuhna a tichhe thei.

"Vision" leh "sight" hi a danglamna a awm em?

Mi tam tak, mithiam tam tak, leh scientist tam tak pawhin "vision" leh "sight" tih thumal hi an hmang dun a ni. Mahse thil inang an ni hauh lo. Thil i hmuh tak tak loh pawhin i hmuh theihna i hmang thei (entir nan, i rilruah lem siamin). Tin, thluak dinhmun thenkhat, i thluak in i mit atanga i thil hmuhte a hrilhfiah theihna tichhe thei a awm bawk. Hei hi tlem tal sawifiah tur chuan: Mit hi taksa chakna mai a ni. Chu chu i mit hian êng a hmuchhuak a, electrical leh chemical signal-ah a chantir a, i thluak lamah a thawn chhuak tihna a ni. Vision hian i mit atanga signal lo chhuakte hrilhfiah thiam a ngai a ni. Chutiang hriatthiamna tel lo chuan i mitin i thluak lama signal a thawn chu a tangkai lo. Heng pahnih hi a hranpa anga ngaih chu thil mak tak angin lang mah se, thluak dinhmun, mit tibuai lova mit hmuhna tichhe thei thil a awm. Entirnan Visual Agnosia tih condition hi a ni. Hetiang natna vei te hian mit an hmu tha a, mahse an thluak hian an thil hmuh chu awmzia a nei thei lo. Hei hi entirnan chiang tak dang chu hmel hriat theih lohna (`Prosopagnosia` emaw `Face Blindness`) hi a ni. Hêng mite hian hmêl hmu thei mah se, tu nge an nih an hre thei lo. Thil awmdan vanduaithlak tak a ni lawm ni?

Engtin nge kan mit hlu tak hi kan humhim ang? Heng thilte hi ti ngei ang che!

I mit hmuhna vawng nung tur leh humhim turin thil engemaw zat i tih theih a awm. A pawimawh zual thenkhat chu:

• Mit enfiah fo a pawimawhzia: Mi zawng zawng, mit hmuh dan pangngai (`20/20 vision`) nei te pawhin an mit enfiah fo tur a ni. Mit enfiahna hian harsatna i hriat loh emaw, i hmuh loh emaw pawh a hmu thei a ni. Refractive errors , hnai taka hmuh theihna (`Myopia`) emaw , hla taka hmuh theihna (`Hyperopia`) te hian mit hmuhna a tichhe thei a ni. A tir lamah chuan i hre lo mai thei. Mit enfiahna hian heng harsatnate hi i hriat hmain a hmuchhuak thei a ni.

• I mit venhim a pawimawh: I mit chhiat theihna tur dinhmunah chuan i mit venhim a pawimawh hle. Safety goggles emaw glasses , face mask emaw shield emaw hian hei hi a pui thei a ni. Sunglass hi mit venna tha tak a ni bawk. UV rays tha lo laka i mit an venghim thin.

• Nutrition pawh ngaihtuah bawk ang che: I mit a thawk tha theih nan vitamin thenkhatType leh nutrient hrang hrang a mamawh a ni. Hemi chungchanga zawhna i neih chuan i chhungkaw doctor emaw mit lam doctor emaw i zawt thei ang.

• Taksa tihchak theihnghilh suh: I mit hriselna hi i taksa pum hriselna nen a inzawm tlat a ni. Taksa tihchak fo hian i mit (leh i taksa dang zawng zawng) chu a hrisel theih nan a pui thei a ni.

• Meizial leh zuk leh hmuam hman loh tur: Meizial zuk, vaping, leh zuk leh hmuam chewing hian i hriselna leh mit hmuhnaah nghawng tha lo tak a nei thei a ni. Zuk leh hmuam hman bânsan (a nih loh leh ṭan ngai loh) hian danglamna nasa tak a thlen thei a ni.

• I mit hmuhna lama inthlak danglamna, mitdelna ang chi i tawn chuan damdawi lam pan nghal rawh! Hengte hi harsatna lian tak chhinchhiahna hmasa ber a ni thei. Sudden, beisei loh taka mit hmuhna hloh hi damdawi lam pan chhan a ni. Damdawi lam harsatna i neih chuan mitdelna emaw, inthlak danglamna emaw a thlen thei a nih chuan i doctor emaw mit lam doctor emaw chuan damdawi lam pan hun tur a hrilh ang che.

Take-Home Thuchah a ni

Mi tam tak tan chuan vision hi nitin an hman sense pawimawh ber a ni. Thiamna awlsam tak angin lang mahse, a takah chuan i taksaa thil kalphung buaithlak ber pawl a ni. I mit hmuhna chu a ṭhat ber tûra a thawh theih nân, i mit pêng zawng zawng, mit (retina), mit nerve, leh thluak zawng zawngte hi a ṭhat theih nân an thawk ho vek a ngai a ni.

I mit hlu tak ven nan thil tam tak i tih theih a ni. Tichuan, i hmuh theih loh thilte ngaihtuah buai ai chuan, i hmuh duh thilte chu i ngaihtuah thei ang. Chuvangin, i mit hi uluk taka enkawl theihnghilh suh!

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` Mit hmuhna, Mit hmuhna, Retina, Optic Nerve, Mit Hriselna