Why not Use convex lens for Myopia »?? please explain with a ray diagram why it is not so..?

Myopia is one of the defects of vision and is also known as near-sightedness.A person with myopia can see nearby objects clearly but cannot see distant objects distinctly.Such a myopic person has the far point nearer than infinity and may see clearly upto a distance of a few metres.In a myopic eye,the image of a distant object is formed in front of the retina and not at the retina itself. This defect may arise due to--
(i) excessive curvature of the eye lens,or
(ii) elongation of the eyeball.
It can be corrected by using a concave lens of suitable power which bring the image back on to the retina and thus the defect is correctected.Since the nature of the problem of nearsightedness is that the light is focused in front of the retina,a diverging lens,concave and not the converging lens i.e convex can be used.Since diverging lens will serve to diverge light before it reaches the eye.This light will then be converged by the cornea and lens to produce an image on the retina.