what is the difference between myopia and presbyopia?
Dear Student,
Myopia is a defect of vision in which a person clearly sees all the nearby objects but is unable to see the distant objects comfortably. A myopic eye forms the image of a distant object in front of its retina.
Myopia is caused by
(i) Increase in curvature of the lens
(ii) Increase in length of the eyeball
Myopia is corrected using a concave lens.
Presbyopia is a common defect of vision which generally occurs at old age. A person suffering from this type of defect of vision cannot see nearby objects clearly and distinctively. A presbyopic eye has its near point greater than 25 cm and it gradually increases as the eye becomes older.
It may also happen that a person suffers from both myopia and hypermetropia. This type of defect can be corrected by using bi-focal lenses. A bifocal lens consists of both convex lens (to correct hypermetropia) and concave lens (to correct myopia).
Hope you got the answer!
@Deni, Good answer, we really appreciate your contribution to this forum, Keep up the good work!
Cheers!