The cornea is the first major refractive surface of the eye and is responsible for over two thirds of its overall dioptric power.
Corneas with a steep surface slope have a small radius of curvature and high dioptric power, while corneas with a flat surface slope have a large radius of curvature and low dioptric power.
Accommodation is the process whereby the crystalline lens changes its dioptric power
to focus precisely and maintain the object of interest at the high-resolution fovea .
McLeod and colleagues proposed a simple formula to approximate the power change occurring with axial anterior shift of an AIOL optic: [DELTA]Dc [approximately equal to] (Dm/ 13) x [DELTA]s (Equation 1) where [DELTA]Dc is the change in the eye's dioptric power
, Dm is the power (D) of the AIOL, and As is the change in lens position (mm).