Normally, light is focused by the cornea and lens
to form a sharp image on the retina. Sometimes
the eyeball is too long for the shape of the
cornea, so the light comes to a focus before it
reaches the retina. As a result, objects in the distance are blurred
although close objects are usually clear. Short-
sightedness can be corrected by spectacles or
contact lenses. These lenses correct the vision
so that distant objects are clear once again. |