Refraction is the optical bending of light
by which an image of the objects in your view is focused upon
the retina, your eyes' light-sensitive lining. In a normally
sighted eye, the focus is precise and the retinal image is
sharp. When a flaw exists in the eyes' refraction system,
the focus falls either in front of the retina (nearsighted)
or behind the retina (farsighted), or the focus is distorted
(astigmatism). In each case the retinal image is unfocused
and vision is blurred. Conventional correction has traditionally
been accomplished with eyeglasses or contact lenses and until
the early 1970's these were the only choices. Today there
are a number of ingenious options --- alternatives to wearing
glasses or contact lenses. Together, these options are known
as REFRACTIVE SURGERY.
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