Snellen chart

The Snellen Eye Chart is a standard method of measuring visual acuity. A chart is rated for the distance it should be viewed at, and the lowest line that can be read has a visual acuity result number next to it. The standard distance for Snellen charts is 20 feet or 6 meters. Smaller versions are available for use in smaller indoor spaces. The Snellen chart is the most commonly used way of testing if someone has sufficient corrected visual acuity to drive legally. There is no direct correlation between visual acuity and myopia. Your optometrist will use the Snellen chart as a reference, to see what refraction will allow you to read the lowest on the chart.