Question

presbyopia define it​

Answer 1

a visual condition which becomes apparent especially in middle age and in which loss of elasticity of the lens of the eye causes defective accommodation and inability to focus sharply for near vision.

Answer 2

Presbyopia is an eye defect which generally arise in old age. Generally in old age ciliary muscles of the eye starts becoming weak and they lose the capacity of power of accomodation of eye lens and eye lens is also not remain so flexible and have lose the capacity to adjust its focal length in old age so the person can't see the nearer and far off object clearly. It is corrected by using bi focal lens.

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