The cornea is the transparent front portion of the human eye that covers the iris, pupil, and anterior chamber. It serves a critical anatomical role in vision by refracting light along with the lens and the anterior chamber.
This structure accounts for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is roughly 43 dioptres. The shape of the cornea can be modified through various surgical procedures, such as LASIK.