Spherical aberrations
Spherical aberrations are a common optical phenomenon that occurs when light rays passing through the periphery of a lens or cornea are refracted differently than those passing through the center. This can lead to blurry, distorted vision and difficulty seeing in low light conditions.
The cornea is the outermost layer of the eye and is responsible for most of the eye’s refractive power. It is also the primary source of spherical aberrations in the eye. In some patients, the cornea may be too steep or too flat, leading to significant spherical aberrations. This can be corrected through refractive surgery, such as LASIK or PRK, which reshape the cornea to reduce aberrations and improve vision.
Intraocular lenses (IOLs) are artificial lenses implanted in the eye during cataract surgery to replace the natural lens. IOLs can also cause spherical aberrations, especially when they have a fixed spherical shape. However, newer generation IOLs, such as aspheric IOLs, have been developed to minimize spherical aberrations and provide better visual outcomes for patients.