Used to test vision, the Snellen eye chart typically has what single letter in the top row?
Tuesday, October 10, 2017
5:25 PM
Used to test vision, the Snellen eye chart typically has what single letter in the top row?
A
D
E
T
Answer: A Snellen chart is an eye chart that can be used to measure visual acuity. Snellen charts are named after the Dutch ophthalmologist Herman Snellen who developed the chart in 1862. The normal Snellen chart is printed with eleven lines of block letters. The first line consists of one very large letter, typically the letter E. Subsequent rows have increasing numbers of letters that decrease in size. A person taking the test covers one eye from 6 metres or 20 feet away, and reads aloud the letters of each row, beginning at the top.