corrective lens

A corrective lens is a lens worn on or before the eye, used to treat myopia, hyperopia, astigmatism, and presbyopia. The most common types of corrective lenses are eyeglass lenses and contact lenses. Intraocular lenses are also beginning to become common. Myopia (near sightedness) requires biconcave or diverging lenses, whereas hyperopia (far sightedness) requires biconvex or converging lenses.
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