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Question
Distinguish between:
Myopia - Presbyopia
Solution
| Myopia | Presbyopia | |
| 1. | This problem of vision arises due to slight elongation of eyeball or curved lens. | In this problem, the near point of aged people recedes. Also, ciliary muscles lose the capacity to change the focal length ofthe eye lens. |
| 2. | In this defect, human eye can see nearby objects distinctly but unable to see distant objects clearly. | In this defect, aged people find it difficult to see nearby objects comfortably and clearly. Sometimes they are unable to see nearby as well as distant objects clearly. |
| 3. | This defect can be corrected using concave lens of suitable focal length. | This defect can be corrected using bifocal lens in which concave lens is useful for distinct vision and convex lens is useful for near vision. |
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