Question

what is presbyopia ? state its cause. How is it corrected?​

Answer 1

Presbypoia is a defect of vision due to which the old person cannot see the nearby object clearly due to loss of power of accommodation of eye. In the old age due to ciliary muscle becomes weak and eyelens become inflexible I lose its power of accommodation it is corrected by the bifocal lens

Answer 2

presbyopia is the defect that has both nearsightedness and farsighted

reasons: presbiyopia is caused by

1) weakening of the ciliary muscle

2) reduction in the flexibility of the eye lens

explanation: The ciliary muscles become weak ,loses elasticity of eye lens. It becomes less flexible and power of accommodation is lost . A person suffers from both myopia and hypermetropia

correction: This type of defect can be corrected by bi-focal lenses