Question

State reasons for Myopia. With the help of ray diagrams, show the

(a) image formation by a myopic eye, and

(b) correction of myopia using an appropriate lens.

Answer 1

Myopia is a defect of vision in which a person clearly sees all the nearby objects, but is unable to see the distinct object comfortably and his eye is known as myopia eye. A myopic eye has its far pint near that infinity. It forms the image of an distinct object in front of the retina as shown in the figure A.

Myopia can be caused by 

1. increase in curvature if the lens.

2. increase in the length if the eye ball.

Since concave lens has an ability to diverge incoming rays, it us used to correct this defect of vision. The image is allowed to form at thee retina by using a concave lens of suitable power as shown in the figure B.