How do aspheric lens surfaces help correct optical aberrations?

Aspheric lenses are designed to depart from a standard spherical shape to specifically address spherical aberration.

In a traditional lens with spherical surfaces, light rays passing through the outer zones of the lens are refracted differently than those passing through the center, preventing all rays from converging at a single focal point. This results in a blurred image, particularly at large apertures.12

By utilizing a non-spherical, or aspheric, surface, the lens geometry is precisely modified to ensure that rays passing through different parts of the lens are brought into a common focus. This correction allows for sharper image quality across the entire field of view, even when using larger apertures that would otherwise exacerbate spherical aberration in standard spherical lenses.13