Reference notes
The essentials
Set in the orbit, moved by six muscles and protected by the lids.
- Size
- About 24 mm across
- Weight
- Around 7.5 g
- Daily
- Blinks about 15,000 times
- Location
- In the bony orbit of the skull
- Blood supply
- Ophthalmic artery
- Function
- Captures and focuses light
Read all anatomy notes · 7
Cornea
The clear front window; it does most of the eye's focusing.
Iris
The coloured ring; its muscles set the size of the pupil.
Sclera
The tough white outer coat that shapes the eyeball.
Lens
Transparent lens behind the iris that helps focus light on the retina.
Retina
Nervous tissue at the back of the eye. Its photoreceptors convert light into electrical signals.
Vitreous body
Transparent gel filling the space between the lens and retina.
Optic nerve
Carries signals from the retina toward the brain.