Anatomy and Conditions of the Human Eye

Cones

Color receptors in the eye, around 7 million.

Cornea

Transparent eye part, refracts light, 2/3 power.

Iris

Controls pupil size, adjusts light entry.

Lens

Refracts light, focuses images on retina.

Macula

Focuses light, sends detailed images to brain.

Optic nerve

Transmits visual information from retina to brain.

Optic disk

Blind spot on retina, lacks visual receptors.

Retina

Inner eye lining, creates images via light.

Rods

Photoreceptors for low light, around 120 million.

Sclera

Outermost white part of the eye.

Myopia

Nearsightedness, corrected with diverging lens.

Hyperopia

Farsightedness, corrected with converging lens.

Astigmatism

Irregular cornea shape, causes vision distortion.

Cataract

Opaque lens, can be surgically replaced.

Aphakia

Absence of lens, causes farsightedness and complications.

Glaucoma

Disease damaging the optic nerve.

Presbyopia

Age-related focus loss, due to lens hardening.