Question

A person is suffering from both myopia and hypermetropia. $\left(i\right)$What kind of lenses can correct this defect? $\left(ii\right)$ How are these lenses prepared?

Answer 1

Type of lens to correct the defect:

• If a person is suffering from hypermetropia and myopia then the person is suggested to wear a Bifocal lens.
• A concave lens of suitable focal length will correct myopia and a convex lens of suitable focal length will correct hypermetropia.

Preparation of lens:

These lenses are prepared by combining both lenses in such a way that the upper part is the concave lens and the lower part is a convex lens.

Hence, a bifocal lens should be used to correct this defect.