Q17 of 30 Page 88

How are we able to see nearby and also the distant objects clearly?

We are able to see nearby and also the distant object clearly by using bifocal lenses which consists of both concave and convex lens. The upper part of lens is Concave lens which is used for distant vision and the lower part of lens is convex lens which is for nearby objects. Bifocal lens are used in Presbyopia condition when the person can’t see distant as well as nearby objects.


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A person needs a lens of power –4.5 D for correction of her vision.

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