Visual acuity is a measure of how well a person can focus on an object. To test visual acuity, the person may read letters or symbols on a chart from the top down, line by line, covering first one eye and then the other.
A visual acuity score is a ratio comparing the person's performance to that of people who have "normal" vision.
For example, a person who can read what people with normal vision can read at 20 ft (6 m) has 20/20 (6/6) distance vision. The larger the second number, the worse the vision.
|Primary Medical Reviewer||Kathleen Romito, MD - Family Medicine|
|Specialist Medical Reviewer||Christopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology|
|Current as of||May 29, 2013|
WebMD Medical Reference from Healthwise