We have all heard of 20/20 vision, but what does it mean??????
A person with 20/20 vision can see what an average person can see on an eye chart when they are standing 20 feet away.
An eye chart measures clarity or sharpness of vision. The top number refers to your distance in feet from the chart. The bottom number indicates the distance at which a person with normal eyesight can read the same line.
For example, if you have 20/30 vision, it means your vision is worse than average. When you are standing 20 feet from the chart, you can read letters that most people see when they are 30 feet.
20/20 vision is not the best vision. A person can have 20/15 vision, which is sharper than average. If you have 20/15 vision, you can see a line in the eye chart at 20 feet that the average person can only see when they are 15 feet away. Generally, the goal of correcting vision with glasses or contacts is to bring a person’s vision to 20/20