The eye
Eye (eyeball) · bulbus oculi
A fluid-filled ball that focuses light onto a living screen of light sensors.
What it does
Light passes through the clear cornea, the pupil in the coloured iris and the lens, which focus it onto the retina lining the back of the eye. The retina's rods and cones turn light into nerve signals, which travel to the brain along the optic nerve. The tough white sclera holds it all together.
Surprising fact
The image focused on your retina is upside down; your brain flips it the right way up.
Why it matters
The cornea does most of the focusing, so reshaping it with a laser can correct short sight. The lens stiffens with age, which is why most people need reading glasses by their mid-forties.
Nearby
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Sources
Drafted with AI help; awaiting a human fact-check against these sources.
Open in the 3D atlas · Suggest a correction · Not medical advice.
3D models: Z-Anatomy & BodyParts3D (CC BY-SA 4.0 / 2.1 JP). Card text CC BY 4.0.