What is the primary function of the cornea?

The primary function of the cornea is to act as the window of the eye. This transparent outer layer is crucial for allowing light to enter the eye, where it begins the process of vision. The cornea plays a key role in refracting (bending) the light that enters, helping to focus it onto the retina at the back of the eye for clearer vision. Its unique structure and curvature are integral in directing where light travels and ensuring proper focus, which is vital for seeing clearly.

While the cornea does provide some protection to the lens and other internal structures of the eye, its most significant role is its transparency and its ability to refract light. Adjusting light focus and controlling pupil size are functions associated with other structures in the eye, namely the lens and the iris, respectively.