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Refractive Error: Focus (Optics), Light, Human Eye, Visual Acuity, Cylinder (Geometry), Hyperopia, Retinoscopy
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Dieser Artikel gilt, aufgrund seiner Grösse, beim Versand als 2 Artikel!
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| Please note that the content of this book primarily consists of articles
available from Wikipedia or other free sources online. A refractive
error, or refraction error, is an error in the focusing of light by the
eye and a frequent reason for reduced visual acuity. An eye that has no
refractive error when viewing a distant object is said to have
emmetropia or be emmetropic. An eye that has a refractive error when
viewing a distant object is said to have ametropia or be ametropic.
Refractive errors are frequently categorized as spherical errors and
cylindrical errors: Spherical errors occur when the optical power of the
eye is either too large or too small to focus light on the retina.
People with refraction error frequently have blurry vision. When the
optics are too powerful for the length of the eyeball (this can arise
from a cornea with too much curvature or an eyeball that is too long),
one has myopia. |
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i.d.R. innert 7-14 Tagen versandfertig
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