What is a refractive
error?
A refractive error is a defect in the way light passes through the eye. In normal vision, light enters the eye through the cornea and is focused at a single point on the retina at the back of the eye. With a refractive error, light rays do not refract (bend) properly to achieve good focus. Instead, light rays focus in front of the retina, behind the retina, or at two different points. Refractive errors usually result from a defect in the length of the eye or shape of the cornea.
