How close can an object be before it appears blurry?

There is a limit as to how close an object can be to the eye before the lens can no longer adjust its focus. Up to about thirty years of age, the closest an object can be focused is approximately 10 to 20 centimeters (4 to 8 inches). As one grows older, the lens tends to stiffen and it becomes more difficult for the person to focus on close objects. In fact, by the time a person reaches the age of seventy, their eyes cannot focus on objects within several meters of their eyes. As a result, most aging adults need reading glasses to focus on close objects.


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