What is Spherical Aberration?
Spherical aberration describes what happens when light rays entering a refracting (focusing) surface such as the cornea are less strongly focused at the center of the refracting surface and are progressively more focused off center. Images are focused on a series of points, resulting in “blur circles.” Fortunately, the human crystalline lens has optical properties that cancel out and neutralize most of the corneal-surface-induced spherical aberration.
