“20/20 What Do Those Numbers Mean for your Vision”

What does 20/20 Vision Mean? 

 

Having 20/20 vision means that one has “normal visual acuity” or in broken down terms, vision that is normal without any help from equipment that aids vision. 20/20 vision means that a person can see clearly at 20 feet which is what a normal person should visually see.  The concept of 20/20 vision does not mean that people have perfect vision, but does mean that the sharpness and clarity at a distance is clear and normal. Visual acuity is measured with a Snellen Chart which displays a series of letters that progressively get smaller and is displayed at exactly 20 feet away from the patient. Presenting the Snellen Chart 20 feet away from the patientmeans that they are reading the same line of letters at that a person with normal vision sees at 20 feet. 

Another way to break down this concept is that a patient with 20/40 has half normal vision and can see objects at half the normal 20 feet distance. There is in fact better vision than 20/20 for example, 20/15 vision and this is because 20/20 is considered to be normal vision. 20/15 vision means that people can see objects at 20 feet that a person with 20/20 vision can only see at 15 feet.

Levels of Vision: Chart from Eye Care Associates of East Texas

20/20 - Normal vision. Fighter pilot minimum. Required to read the stock quotes in the newspaper, or numbers in the telephone book. 

  • 20/40 - Able to pass Driver's License Test in all 50 States. Most printed material is at this level. 
  • 20/80 - Able to read alarm clock at 10 feet. News Headlines are this size. 
  • 20/200 - Legal blindness. Able to see STOP sign letters.

Find out what your numbers are and schedule and appointment with us today!