astigmatism


astigmatism
ASTIGMATÍSM s.n. Aberaţie a unui sistem optic, care formează o imagine întinsă pentru un obiect. ♦ Defect al lentilelor sau al corneei şi cristalinului ochiului omenesc, care constă într-o abatere de la forma sferică, ele având razele de curbură diferite în două plane perpendiculare, ceea ce duce la deformarea imaginilor. – Din fr. astigmatisme.
Trimis de ana_zecheru, 13.09.2007. Sursa: DEX '98

ASTIGMATÍSM s. (fiz., med.) aberaţie vizuală.
Trimis de siveco, 15.01.2009. Sursa: Sinonime

astigmatísm s. n. (sil. mf. -stig-)
Trimis de siveco, 10.08.2004. Sursa: Dicţionar ortografic

ASTIGMATÍSM astigmatisme n. 1) fiz. Aberaţie a unui sistem optic care dă o imagine deformată. 2) Defect al vederii, cauzat de inegalitatea curburii corneei sau a cristalinului. [Sil. a-stig-] /<fr. astigmatisme
Trimis de siveco, 22.08.2004. Sursa: NODEX

ASTIGMATÍSM s.n. 1. Defect al vederii, datorat faptului că curbura corneei sau a cristalinului este neegală şi face ca ochiul să perceapă obiectele deformate. 2. Defect al unei lentile, care dă o imagine deformată datorită curburii sale neegale. [< fr. astigmatisme, cf. gr. a – fără, stigma – pată].
Trimis de LauraGellner, 25.01.2006. Sursa: DN

ASTIGMATÍSM s. n. 1. defect al vederii datorat unor diferenţe de curbură a corneei sau cristalinului, care fac ca ochiul să perceapă obiectele deformate. 2. defect al unei lentile, care dă o imagine deformată datorită curburii sale neegale. (< fr. astigmatisme)
Trimis de raduborza, 15.09.2007. Sursa: MDN

Dicționar Român. 2013.

Look at other dictionaries:

  • Astigmatism — A*stig ma*tism, n. [Gr. a priv. + ?, ?, a prick of a pointed instrument, a spot, fr. ? to prick: cf. F. astigmatisme.] (Med. & Opt.) A defect of the eye or of a lens, in consequence of which the rays derived from one point are not brought to a… …   The Collaborative International Dictionary of English

  • astigmatism — 1849, coined by the Rev. William Whewell (1794 1866), English polymath, from Gk. a without + stigmatos gen. of stigma a mark, spot, puncture (see STICK (Cf. stick) (v.)) …   Etymology dictionary

  • astigmatism — ► NOUN ▪ a defect of the eye or a lens, resulting in distorted images. DERIVATIVES astigmatic adjective. ORIGIN from Greek stigma point …   English terms dictionary

  • astigmatism — [ə stig′mə tiz΄əm] n. [< Gr a , without + stigma (gen. stigmatos) a mark, puncture (see STICK) + ISM] 1. an irregularity in the curvature of a lens, including the lens of the eye, so that light rays from an object do not meet in a single focal …   English World dictionary

  • Astigmatism — An optical system with astigmatism is one where rays that propagate in two perpendicular planes have different foci. If an optical system with astigmatism is used to form an image of a cross, the vertical and horizontal lines will be in sharp… …   Wikipedia

  • Astigmatism — A common form of visual impairment in which part of an image is blurred, due to an irregularity in the curvature of the front surface of the eye, the cornea. The curve of the cornea is shaped more like an American football or a rugby ball rather… …   Medical dictionary

  • astigmatism — /euh stig meuh tiz euhm/, n. 1. Also called astigmia /euh stig mee euh/. Ophthalm. a refractive error of the eye in which parallel rays of light from an external source do not converge on a single focal point on the retina. 2. Optics. an… …   Universalium

  • astigmatism — Ametropia Am e*tro pi*a, n. [Gr. ? irregular + ?, ?, eye.] (Med.) a visual impairment resulting from faulty refraction of light rays in the eye. Subtypes include {myopia} {astigmatism} and {hyperopia}. {Am e*trop ic}, a. [1913 Webster +PJC] …   The Collaborative International Dictionary of English

  • astigmatism — noun Date: 1846 1. a defect of an optical system (as a lens) causing rays from a point to fail to meet in a focal point resulting in a blurred and imperfect image 2. a defect of vision due to astigmatism of the refractive system of the eye and… …   New Collegiate Dictionary

  • astigmatism — [[t]əstɪ̱gmətɪzəm[/t]] N UNCOUNT If someone has astigmatism, the front of their eye has a slightly irregular shape, so they cannot see properly …   English dictionary