Question

Write an explanation.

near point of the eye 

Answer 1

1. The near point of the eye (also known as the least distance of distinct vision) is the minimum distance at which an object can be placed so that the eye can see it clearly without experiencing any strain.
2. For a young adult with normal vision, the near point is approximately 25 cm.
3. To focus on objects at this close distance, the ciliary muscles in the eye fully contract. This makes the eye lens thicker and more rounded, temporarily increasing its converging power to its maximum limit.
4. As a person ages, the ciliary muscles gradually weaken and the eye lens loses its flexibility. This causes the near point to recede (move further away than 25 cm), making it difficult to read or see close objects clearly. This natural age-related condition is known as presbyopia.