The cornea has a power of approximately how much?

The power of the cornea is primarily responsible for focusing light onto the retina, and it plays a crucial role in the eye's optical system. The typical refractive power of the human cornea is around 43 diopters. This figure is an average that reflects the cornea's curvature and the refractive index of the tissue. Variability can exist among individuals, with some corneas measuring slightly below or above this average, but 43D is widely accepted as the standard reference. This average power contributes significantly to the overall refractive power of the eye, which also includes the contribution of the lens.

Understanding this characteristic of the cornea is pivotal for opticians when considering corneal topography and assessing refractive conditions. It helps in the selection of appropriate corrective lenses or surgical options, clarifying the cornea's central role in vision.