The Snellen eye chart was first designed by a Dutch ophthalmologist, Herman Snellen in 1860s. Other types of commonly used eye charts include the Landolt C, and the Lea test. How to use the eye chart: The Snellen Eye Chart is read while standing 20 feet from the chart. Be sure the room you are in is well lit but is not in full sunlight. Test one eye at a time (cover the other eye with your hand or card etc.). The lowest line that you can read correctly is your visual acuity. At 20 feet (6 meters) you should try to read the letters on the row 6th from the top. If you can read that line ok it means you have visual acuity of 20/40 or better: 1/2 normal.
Posted on: Wed, 03 Jul 2013 02:06:56 +0000
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