An optical aberration is a departure of the performance of an optical system from the predictions of paraxial optics. In an imaging system, it occurs when light from one point of an object does not converge into (or does not diverge from) a single point after transmission through the system. Aberrations occur because the simple paraxial theory is not a completely accurate model of the effect of an optical system on light, rather than due to flaws in the optical elements.
Aberration leads to blurring of the image produced by an image-forming optical system. Makers of optical instruments need to correct optical systems to compensate for aberration.
The articles on reflection, refraction and caustics discuss the general features of reflected and refracted rays.
Famous quotes containing the words optical and/or aberration:
“It is said that a carpenter building a summer hotel here ... declared that one very clear day he picked out a ship coming into Portland Harbor and could distinctly see that its cargo was West Indian rum. A county historian avers that it was probably an optical delusion, the result of looking so often through a glass in common use in those days.”
—For the State of New Hampshire, U.S. public relief program (1935-1943)
“The era of the political was one of anomie: crisis, violence, madness and revolution. The era of the transpolitical is that of anomaly: an aberration of no consequence, contemporaneous with the event of no consequence.”
—Jean Baudrillard (b. 1929)