ocular refraction

ocular refraction

Etymology: L, oculus, eye, refringere, to break apart

the refraction of the eye.

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refraction [re-frak´shun]

the act or process of refracting; specifically, the determination of the refractive errors of the eye and their correction with glasses.

the deviation of light in passing obliquely from one medium to another of different density.

cycloplegic refraction a type of static refraction, measured after lens accommodation is paralyzed by administration of cycloplegic eye drops.

double refraction refraction in which incident rays are divided into two refracted rays.

dynamic refraction refraction of the eye during accommodation.

ocular refraction the refraction of light produced by the media of the normal eye and resulting in the focusing of images upon the retina.

static refraction refraction of the eye when its accommodation is paralyzed.

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refractive error 

The dioptric power (K) of the ametropia of the eye. It is equal to 1/k in dioptres, where k is the distance between the far point and either the spectacle plane (spectacle refraction), or the principal point of the eye, or the refracting surface of the reduced eye (ocular refraction), in metres. Thus

K = 1/k

when the eye is situated in air. Syn. ametropia (although this is not strictly so as ametropia is the anomaly); refraction of the eye; refractive status; static refraction. See far point of accommodation; Scheiner's experiment.