Q17 of 53 Page 1

What eye defect is hypermetropia? Describe with a ray diagram how this defect of vision can by corrected by using an appropriate lens.

A person is said to hypermetropia, if the person is not able to see nearby objects but can see distant objects.


The causes of Hypermetropia are as follows:


1. Increase in the focal length of eye lens.


2. Due to shortening of the eyeball.


The hypermetropia defect can be corrected with the help of convex lens of suitable power. When concave lens having suitable power is placed in forward of the eye which is having defect of hypermetropia, the diverging light rays coming from the object are converged by the convex lens and thus results in formation of a virtual image of the object and the eye can easily focus the image formed by convex lens.



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