20/20 Vision

Snellen Eye ChartWhat exactly does 20/20 vision mean?


     20/20 vision is what we strive for.  It is often considered “normal standard vision”.  What 20/20 means scientifically is that an individual can identify a letter of a pre-determined size (8.75cm) from 20 feet away.


What if a person’s vision is less than “standard”, say 20/100?


     This means what that individual can see at 20 feet, an individual with “standard 20/20” vision can see at 100ft.  In other words the person with 20/100 vision needs to be 5x closer to the letter or have the letter be 5x larger to view it.