Visual acuity is measured using an eye chart in the Optometrists office.
“Normal” vision is 20/20. This means that the test subject sees the same line of letters at 20 feet that a normal person sees at 20 feet. 20/40 vision means that the test subject sees at 20 feet what a normal person sees at 40 feet.
Levels of Vision
- 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.
