Eyeglass prescription

An eyeglass prescription is a written order by an ophthalmologist or an optometrist to an optician for eyeglasses. It specifies the refractive power to which the eyeglasses are to be made in order to correct blurred vision due to refractive errors, including myopia, hyperopia, astigmatism, and presbyopia. It is typically determined using a phoropter or an automated refractor.
See more at Wikipedia.org...