Cornea

What is it?

Most people mistake the cornea for the whitish areas in your eye-this white area is called the sclera. In fact, the cornea is not white at all, but a clear film over bulging part of your eye. The cornea only covers the iris. The rest of the outer layer of the eye is the conjunctiva. This and the lens are the two parts of the eyes that must remain transparent and clear. Amazingly, the cornea does not have any blood vessels. Nutrients and oxygen are supplied directly by the tears and the aqueous humor (the liquid right underneath it). Because there are no blood vessels to rupture here, this means that minor cuts in the cornea can heal back easily. This feature of the cornea is what makes laser eye surgery so successful.

What does it do?

Its main purpose is to focus light into the eye. The cornea is the only outer area where light is allowed into the eye. The cornea's bulging shape accounts for 80% of the eye's focusing. It bulges just like a magnifying glass.

<—back