Posted by Aldrin on Nov. 22, 2013, 8:28 p.m.
Myopia is the term used to define short sightedness. Light
from a distant object forms an image before it reaches the retina. This could
be because the eye is too long, or the cornea or crystalline lens is too
strong.
A myopic person has clear vision when looking at
objects close to them, but distant objects will appear blurred.
Hypermetropia means long sight and is where the
image of a nearby object is formed behind the retina. This could be because the
eye is too short, or the cornea or crystalline lens does not refract the light
enough.
A hypermetropic person may have blurred vision when
looking at objects close to them, and clearer vision when looking at objects in
the distance. By placing a convex (plus powered) lens in front of a
hypermetropic eye, the image is moved forward and focuses correctly on the
retina.