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.