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emmetropia
 emmetropiaem·me·tro·pi·a E0113700 (ĕm′ĭ-trō′pē-ə)n. The condition of the normal eye when parallel rays of light are focused exactly on the retina and vision is perfect.
[Greek emmetros, well-proportioned, fitting (en, in; see en-2 + metron, measure; see meter2) + -opia.]
em′me·trop′ic (-trŏp′ĭk, -trō′pĭk) adj.emmetropia (ˌɛmɪˈtrəʊpɪə) n (Physiology) the normal condition of perfect vision, in which parallel light rays are focused on the retina without the need for accommodation[C19: from New Latin, from Greek emmetros in due measure + -opia] emmetropic adjem•me•tro•pi•a (ˌɛm ɪˈtroʊ pi ə)
n. the normal refractive condition of the eye in which the rays of light are accurately focused on the retina. [1860–65; < Greek émmetr(os) in measure, fitting] em′me•trope`, n. em`me•trop′ic (-ˈtrɒp ɪk, -ˈtroʊ pɪk) adj. emmetropia, emmetropythe normal refractive function of the eye in which light is focused exactly on the retina with the eye relaxed. — emmetropic, adj.See also: EyesThesaurus| Noun | 1. | emmetropia - (ophthalmology) the normal refractive condition of the eye in which there is clear focus of light on the retinaophthalmology - the branch of medicine concerned with the eye and its diseasesphysical condition, physiological condition, physiological state - the condition or state of the body or bodily functions |
Emmetropia
emmetropia[‚em·ə′trō·pē·ə] (medicine) Normal vision. Emmetropia normal, or correct, refraction of the eye, as opposed to incorrect refraction, or ametropia, in which the optical system is unable to bring into focus on the retina the parallel light rays entering the eye. emmetropia
emmetropia [em″ĕ-tro´pe-ah] the ideal optical condition, parallel rays coming to a focus on the retina. adj., adj emmetrop´ic.em·me·tro·pi·a (em'ĕ-trō'pē-ă), Do not confuse this word with ametropia.The state of refraction of the eye in which parallel rays, when the eye is at rest, are focused exactly on the retina. [G. emmetros, according to measure, + ōps, eye] emmetropia (ĕm′ĭ-trō′pē-ə)n. The condition of the normal eye when parallel rays of light are focused exactly on the retina and vision is perfect.
em′me·trop′ic (-trŏp′ĭk, -trō′pĭk) adj.em·me·tro·pi·a (em'ĕ-trō'pē-ă) The state of refraction of the eye in which parallel rays, when the eye is at rest, are focused exactly on the retina. [G. emmetros, according to measure, + ōps, eye] EMMETROPIA, MYOPIA, HYPEROPIA EMMETROPIA, MYOPIA, HYPEROPIA EMMETROPIA, MYOPIA, HYPEROPIAemmetropia (em?e-tro'pe-a) The normal condition of the eye in refraction in which, when the eye is at rest, parallel rays focus exactly on the retina. See: illustration; astigmatism; myopiaemmetropia The state of the normal eye, with relaxed ACCOMMODATION, in which light rays from a distance (parallel rays) focus accurately on the retina giving perfect vision.emmetropiaThe refractive state of the eye in which, with accommodation relaxed, the conjugate focus of the retina is at infinity. Thus, the retina lies in the plane of the posterior principal focus of the eye and distant objects are sharply focused on the retina. This is the ideal refractive state of the eye. Note: the concept of emmetropia is not simple because accommodation is not inactive when fixating at distance (tonic accommodation). In fact, some authors consider hypermetropia of up to 1.00 D, in a pre-presbyope, as emmetropia. See resting state of accommodation; ametropia; conjugate distances.emmetropia
Related to emmetropia: ametropiaWords related to emmetropianoun (ophthalmology) the normal refractive condition of the eye in which there is clear focus of light on the retinaRelated Words- ophthalmology
- physical condition
- physiological condition
- physiological state
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