18/01/1908 Dutch ophthalmologist Herman Snellen dies
Unit 4 - Snellen Chart
He Introduced the Snellen chart to study visual acuity. A person taking the test covers one eye from 6 metres and reads aloud the letters of each row, beginning at the top. The smallest row that can be read accurately indicates the visual acuity in that specific eye. The chart was later developed into similar but more practical LogMAR chart.