Panon

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Artikel ieu nujul ka organ panempo. Tempo Panon (disambiguasi) pikeun guna séjénna.

Panon manusa cenah mangrupa jandéla jiwa

Panon ngarupakeun hiji organ nu boga tujuan pikeun ngariksa cahya. Panon nu pangbasajanna teu migawé lian ti ngariksa naha sakuriling téh caang atawa poék. Panon nu leuwih kompléks dipaké pikeun nyadiakeun rasa sawangan.

Panon majemuk dipimilik ku arthropod (serangga jeung sabangsana), nu disusun ku fasét-fasét basajan nu ngahasilkeun pixelated image (lain sababaraha gambar sakumaha nu disangka).

Pikeun kalolobaan vertebrata jeung sababaraha molluska, fungsi panon nyaéta pikeun ngeunteungkeun (proyéksi) gambar kana rétina nu peka ku cahya, nu lajeng ditransmisikeun ngaliwatan saraf optik ka uteuk. Panon bentukna buleud, dieusi ku zat kawas jél transparan nu disebut vitreous humour, lajeng lénsa jeung otot nu disebut iris nu ngatur kadar cahya nu asup.

Mokuskeun

Sangkan bisa fokus, cahya nu asup kudu diréfraksikeun. Jumlah réfraksi nu diperlukeun gumantung kana jarak objék nu keur ditempo. A distant object will require less bending of light than a nearer one. Most of the refraction occurs at the cornea which has a fixed curvature. The remainder of the required refraction occurs at the lens. The lens can be pulled flatter or rounder by muscles, which adjust the power of the lens. As we age we lose this ability to adjust the focus. Such a condition is known as presbyopia. There are other refraction errors arising from the shape of the cornea and lens, and from the length of the eyeball. These include myopia, hyperopia, and astigmatism.

Tempo site ieu pikeun diagram panon nu hadé [1]