Anatomy of the Eye
Visual Disorders

Near-sightedness
Far-sightedness
Astigmatism
Near-sightedness
If an eye is too long, light rays are focused into a point in front of the retina when looking into the distance. The near-sighted person therefore has a blurred vision of distant objects. Near-sightedness can be corrected with concave glasses or adequate contact lenses. They make the light rays focus on the retina creating a sharp, focused image.

The treatment with the Excimer-Laser or the LASIK method can "flatten" the cornea, and thus adjust it to the point in which the rays are focused.