When measuring your “visual acuity” (clarity of vision), you are generally tested to determine how clear your eyesight is from a distance of 20 feet. A person with 20/20 vision is able to clearly see all objects that should normally be visible at a 20-foot distance. LASIK eye surgery can potentially correct your vision to 20/20 or better.
Comparatively, someone with 20/100 vision needs to stand 20 feet away from a particular object in order to see it as clearly as a person with 20/20 vision can see it at 100 feet.
20/20 Vision is Not Perfect Vision
Contrary to popular belief, just because you have 20/20 vision does not mean your eyesight is perfect. Several other key factors can influence your visual acuity, including:
- Eye coordination
- Depth perception
- Peripheral vision
- Focusing ability
20/20 vision is considered the standard for good vision, but it is not the best possible vision you can have. Some people who receive LASIK enjoy 20/15 vision or better.
Using an Eye Chart to Measure Vision
There are several different types of eye charts that can be used to measure vision, but the most common is the Snellen eye chart, which uses eleven rows of capital letters to test for visual acuity.
In most cases, if you are able to read the large “E” at the top of a Snellen eye chart, but cannot distinguish any letters below it, your visual acuity is considered 20/200. This means that someone with 20/20 vision would be able to read the same letter while standing a full 200 feet away.
You are considered legally blind if your best-corrected vision is 20/200 or worse. In most of the United States, your corrected vision must be at least 20/40 in order for you to qualify for a driver’s license.
If you want to experience clear vision without the hassle of glasses and contact lenses, please contact Doctors For Visual Freedom today to schedule a free LASIK screening with our experienced Chicago LASIK surgeon Dr. Mark Golden.