Most people are familiar with what has become recognized as a standard eye chart, and nearly everyone has heard about “20/20 vision;” but what does 20/20 vision mean? It is the standard that everyone strives to achieve; however, few people understand what this designation actually represents.
The numbers 20/20 represent a measure of visual acuity, which is the ability to see symbols and objects clearly from a distance. Visual acuity is typically tested using the Snellen chart, which is made up of 11 rows of letters, with each row containing smaller letters toward the bottom of the chart. On this eye chart, each line of letters is assigned a different number ranging from 10 to 200. The number of the line accounts for the lower number in the visual acuity measurement; the top number refers to the number of feet away from the chart that a person stands when having their visual acuity tested. Normal visual acuity is measured as 20/20 vision; it means that a person who is standing 20 feet away from the chart can read the line that is designated 20/20. Someone with 20/10 vision has better-than-normal vision; someone with 20/200 vision has poorer-than-normal vision.
People with poorer-than-normal vision often require some form of vision correction to achieve normal visual acuity. Achieving 20/20 vision depends on many factors, including personal preference, genetics and other health factors that may limit some options. Eyeglasses or contact lenses often can be used to correct visual acuity to achieve normal vision, while other times LASIK surgery offers a more permanent solution. If you would like to learn more about how you can improve your visual acuity, Moretsky Cassidy LASIK would be happy to answer your questions.