
ntsephysics.blogspot.com
NTSE PhysicsThursday, May 5, 2011. Is a vision condition in which the crystalline lens of the eye loses its flexibility, that makes it difficult to focus on close objects. The loss of flexibility takes place over a number of years. Presbyopia usually becomes noticeable in the early to mid-40's. Presbyopia is a natural part of the aging process of the eye. It is not a disease, and it cannot be prevented. Your optometrist can prescribe reading glasses, bifocals or contact lenses. Persons with astigmatism have several.
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