Aberration
Distortions, related to astigmatism , that cause the inability of light rays entering the eye to converge (come together) to a single focus point on the retina . Aberration are divided into two main categories: higher-order and lower-order. Optical system image defects; rays of light emanating from an object-point fail to form a perfect image-point.
Related Links
Aberrations of the eye – an overview — ScienceDirect Topics
Higher-Order Aberrations in the Eye – AllAboutVision.com
Diopters, Aberration, and the Human Eye (video) — Khan Academy
Optical aberrations and alignment of the eye with age — JOV — ARVO Journals
OSA — Chromatic aberration correction of the human eye for retinal imaging in the near infrared
Dynamics of the eye’s wave aberration. – PubMed – NCBI