- Aberration
- (1) A deviation or irregularity. For example, a chromosome aberration is a deviation from the normal chromosome number or the normal chromosome structure. In this sense, aberration is also synonymous with deflection, departure, divergence, diversion, turning. (2) A mental aberration is a significant deviation from normal mental activity. In this sense, aberration is synonymous with mental derangement, mental illness, psychopathy.
* * *1. Deviating from the normal course or pattern. 2. Deviant development or growth. SEE ALSO: chromosome. [L. aberratio]- chromatic a. the difference in focus or magnification of an image arising because of a difference in the refraction of different wavelengths composing white light. SYN: chromatism (2), color a., newtonian a..- chromosome a. any deviation from the normal number or morphology of chromosomes; also the phenotypic consequences thereof.- coma a. 1. the distortion of image formation created when a bundle of light rays enters an optical system not parallel to the optic axis. 2. in botany, any tuft, as the hairs on a seed, or the greenery on a radish or a pineapple. SYN: coma (3). [G. kome, hair, foliage]- curvature a. lack of spatial correspondence causing the image of a straight extended object to appear curved.- dioptric a. SYN: spherical a..- distortion a. the faulty formation of an image arising because the magnification of the peripheral part of an object is different from that of the central part when viewed through a lens. SEE ALSO: Petzval surface.- lateral a. in spherical a., the distance between paraxial focus of central rays on the optic axis.- longitudinal a. in spherical a., the distance separating the focus of paraxial and peripheral rays on the optic axis.- mental a. disturbed thought or behavior that connotes a psychological or psychiatric impairment. See delusion.- monochromatic a. a defect in an optical image arising because of the nature of lenses; the main types are spherical, coma, curvature, and distortion a., and astigmatism of oblique pencils.- newtonian a. SYN: chromatic a..- optical a. failure of rays from a point source to form a perfect image after traversing an optical system.- spherical a. a monochromatic a. occurring in refraction at a spherical surface in which the paraxial and peripheral rays focus along the axis at different points. SYN: dioptric a..
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ab·er·ra·tion .ab-ə-'rā-shən n1) failure of a mirror, refracting surface, or lens to produce exact point-to-point correspondence between an object and its image2) unsoundness or disorder of the mind3) an aberrant organ or individualab·er·ra·tion·al -shnəl, -shən-əl adj* * *
n.(in optics) a defect in the image formed by a lens. In chromatic aberration the image formed by a lens has coloured fringes as a result of the different extent to which light of different colours is refracted by glass. It is corrected by using an achromatic lenses. In spherical aberration, the image is blurred because rays from the object come to a focus in slightly different positions as a result of the curvature of the lens: the rays passing more peripherally through the lens are bent more than those passing through centrally. This occurs even with monochromatic light.* * *
ab·er·ra·tion (ab″ər-aґshən) [L. aberratio, q.v.] deviation from the usual course or condition. unequal refraction or focalization of light rays by a lens, resulting in degradation of the image they produce. in cardiology, aberrant electrical impulse conduction.
Medical dictionary. 2011.
