During the break, a person focuses on an object that is at least 20 feet away, which relaxes the eye muscles. The following methods can help put this rule into practice: Also, remembering to blink ...

When a person has 20/20 vision, they can see with standard visual acuity. This refers to the sharpness or clarity of an object 20 feet away. The general standard that corrective measures try to ...

That means if an object is 200 feet away, you have to stand 20 feet from it in order to see it clearly. But a person with normal vision can stand 200 feet away and see that object perfectly.