Astigmatism is corrected by using

Options

(a) cylindrical lens
(b) plano-convex lens
(c) plano-concave lens
(d) convex lens

Correct Answer:

cylindrical lens

Explanation:

In this defect, eye cannot perpendicular directions clearly that is horizontal and vertical lines simultaneously. It is due to imperfect spherical nature of eye lens. This defect can be removed by using cylindrical lenses.