It’s a common misconception that 20/20 vision means you have “perfect” eyesight. What it actually means is that you have sharp visual acuity. Still, other important visual skills—such as eye coordination, peripheral awareness, depth perception, focusing ability, and color vision—also contribute to your overall visual ability.
What is an Eye Chart?
Eye charts were developed in 1862 by Dutch ophthalmologist Herman Snellen. That’s why you may hear optometrists call them Snellen charts. The fraction 20/20 is also referred to as a Snellen fraction.
Is 20/20 Vision the Best Vision You Can Have?
20/20 is the term used to describe normal visual acuity. It means you can identify the line of letters on a standardized eye chart that someone with standard vision can see from 20 feet away.
But 20/20 is not the best vision you can have. If you can see the letters on the line below the 20/20 line without stepping closer to the chart, this means you have a 20/15 vision. In other words, you can see from 20 feet away what the average person can only discern from a distance of 15 feet. Even 20/10 vision is possible, meaning your visual acuity is twice as sharp as someone with 20/20 vision.
Why Do Some People Have Less Than 20/20 Vision?
Clarity of vision can go in the other direction as well, signifying poor visual acuity. Snellen fractions such as 20/30 and 20/50 mean that you need to stand 20 feet from the chart to identify letters that someone with normal vision could discern from 30 or 50 feet back. The large “E” at the top of every Snellen chart corresponds to 20/200 vision.
Eye charts effectively identify myopia (nearsightedness), or the ability to focus on objects up close but not far away. However, some people have the opposite problem, meaning they can see objects clearly at a distance but struggle to bring near objects into focus. This is known as hyperopia (farsightedness). Presbyopia, or the gradually declining ability to focus on near objects, is a natural part of aging. Other conditions, such as astigmatism or eye disease, can also affect the clarity of vision.
Who Needs Eye Exams?
The ability to read the 20/20 line on an eye chart doesn’t mean you should skip regular eye exams. After all, your doctor doesn’t just check your visual acuity—they also evaluate your overall eye health, look for signs of changing vision, and diagnose problems like glaucoma and cataracts that may not show symptoms yet. This is why you should visit the eye doctor at least once every year or two, depending on your age, health history, and vision needs.
Eye Center of Northern Colorado provides the services you’re looking for. With offices in Fort Collins, Loveland, and Greeley, we serve Northern Colorado with the highest quality eye care available. Our services are second to none, leveraging the best technology to test, diagnose, and treat vision problems. To ask questions or schedule your next appointment, please contact us today.