Most of us consider 20/20 vision pretty gosh darn perfect, but have you ever wondered what it actually means? It’s a standard used to measure how good one’s eyesight is, but, again, what’s it all about? Well, the answer might surprise you. While you might imagine it means something rather complicated and technical about your vision, but, in a way, it’s a fairly simple concept. During routine eye exams, as we all know, your doctor will have you read from an eye chart a certain distance away. Guess how far that chart is? Yep, 20 feet. Read on and we’ll get into some interesting specifics to help put what it means to have 20/20 vision in clear focus.
You’ve Aced The Snellen Chart
Now, you might already be doubting us. You’ve been in your doctor’s office, and there’s not even enough room for a chart to be 20 feet away from you, right? In a smaller office room, this may certainly be true. While the chart can literally be 20 feet away from you, it can also be projected in a way that equals what it would be like if it were truly 20 feet away from you. Pretty nifty, huh? In this way, physicians have created a standardized exam, which helps differentiate vision using a single system. The exam used is known as the Snellen chart and is integral to determining whether or not a patient has 20/20 vision. It lists out black letters on a white background, which slowly get smaller and smaller as you work your way down it.
Your Vision Isn’t Completely Perfect…
If you’ve done this exam with your doctor and he or she has told you that you have 20/20 vision that means you can see what would be expected, or what is average for a person to clearly read a letter that is 20 feet away. So, this is where we have to tell you—it doesn’t mean you have some sort of phenomenal eyesight (sorry). But it also doesn’t mean you have bad vision by any means! Remember, this is an average number, meaning you can see what most people can, so it’s really good for you!
With that said, it also means that some people actually have better vision than 20/20. Is your mind blown yet? That’s right, it’s possible to have 20/15, 20/10, 20/5…or even better! Before you get carried away, you should know that it’s quite rare for a person to have 20/10 or better vision. When you get into that realm of vision, it’s reserved more for animals, such as birds. In fact, many birds of prey have 20/5 or even better eyesight.
…But, It Is Better Than Most
The scale goes the other way, too, and for those of you with poor vision, you might already know what we’re talking about. 20/30, 20/40 and more go in the opposite direction, and means a person sees worse than average using the 20 feet scale. A person with 20/30 vision, for example, see at 20 feet what a normal person would see at 30. At 20/40, a person can only see about half as good as the 20/20 average. In order to pass a driver’s license test in the U.S., a person must have 20/40 vision or better. When a person can only read at a 20/200 level they are considered legally blind.
Luckily, most vision problems below 20/20 can be fixed with the use of a prescription for glasses or contacts. While they certainly won’t cure the issue, they can allow a person to go throughout their day with eyesight just as good as anyone else on average. Best yet, with contacts, no one even has to know! Plus, you have the advantage of slipping in a colored pair, like Air Optix Colors or FreshLook Colorblends, every now and again to really switch up your look—all while improving your vision. A win/win if you ask us!