#coma aberration

• Aplanatic — Pertaining to or relating to aplanatism; an optical system (objective, lens, or mirror) that is rigorously corrected for both spherical aberration and coma aberration (Abbe's sine condition). This high-precision system allows the formation of a perfectly sharp and point-like image for an object located on the main optical axis, eliminating asymmetrical distortions of light beams.
• Aplanatism — The property or geometric condition of an optical system to simultaneously correct and eliminate both spherical aberration and coma aberration for a given point-like object. This physical phenomenon is achieved through strict compliance with Abbe's sine condition, ensuring the formation of exceptionally sharp and perfectly stigmatic images in the vicinity of the main optical axis.