Question

Mr. Backson, a 55-year-old man, experiences difficulty seeing clearly, especially for reading. He is fade up by blurry vision at close distances, while distant objects appear relatively better. After examination, his eye doctor diagnosed that his eye lens has become less flexible and opaque.

A person's near point is at 45 cm and far point is at 2 m. What kind of corrective lens is BEST suited for his vision defect?

An old person is suffering from an eye defect caused by weakening of ciliary muscles and diminishing flexibility of the eye lens. If the defect of vision is 'a' which can be corrected by lens 'b', then 'a' and 'b' respectively are :

A person suffering from presbyopia needs bifocal lens. If he needs two lens of power −4·0 dioptre and + 2·0 dioptre, which one of these two lenses is for the correction of distant vision and what is its focal length ?