List three common refractive defects of vision. Suggest the way of cor

1.	List three common refractive defects of vision. Suggest the way of correcting these defects.
Answer» The three common refractive defects of vision are as follows : Myopia (short-sightedness) : It is corrected by using spectacles having concave lenses of appropriate power. Hypermetropia (far-sightedness) : It is corrected by using spectacles having convex lenses of appropriate power. Presbyopia : This defect is corrected using bifocal lenses of appropriate power in which the upper part consists of a concave lens (to correct myopia) and the lower part consists of a convex lens (to correct hypermetropia).

List three common refractive defects of vision. Suggest the way of correcting these defects.

Answer»

The three common refractive defects of vision are as follows :

Myopia (short-sightedness) : It is corrected by using spectacles having concave lenses of appropriate power.

Hypermetropia (far-sightedness) : It is corrected by using spectacles having convex lenses of appropriate power.

Presbyopia : This defect is corrected using bifocal lenses of appropriate power in which the upper part consists of a concave lens (to correct myopia) and the lower part consists of a convex lens (to correct hypermetropia).

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