Question

(iv) Astigmatism: It is a defect in the eye or in a lens caused by a deviation from spherical curvature, which results in distorted images, as light rays are prevented from meeting at a common focus. It can be corrected by using a convex lens or concave lens or both.

Answer 1

Answer:

Astigmatism is occured due to old age.

Both lens are used in this case.

Explanation:

Answer 2

Answer:

Astigmatism is occured due to old age

In this defect we can use both lens.

Hope it helps u

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