Visual acuity

Visual acuity is the eye's capacity for detecting fine details and is the quantitative measure of the eye’s ability to see an in-focus image at a certain distance. The standard definition of normal visual acuity (20/20 vision) is the ability to resolve a spatial pattern separated by a visual angle of one minute of arc. In the United States of America, it is expressed relative to 20/20. A visual acuity of 20/20 means that you can see what the average person can see from 20 feet away. If one has a visual acuity of 20/40, that person would be able to detect details from 20 feet, that a normal person would be able to see from 40 feet. A person with a visual acuity of 20/200 is legally blind. Visual acuity is often measured by an optometrist with the help of a Snellen chart. Category:Ophthalmology