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Snellen Pocket Eye Chart
Conversion of LogMar Visual acuity into Snellen
Calculation of Snellen's Letter size
Snellen Chart - A Complete Tutorial.
Snellen Eye Chart - a Description and Explanation - Precision Vision
Which font is used in Snellen charts (also known as eye exam charts)? - Quora
Calculation of Snellen's Letter size - Snellen视力表计算_哔哩哔哩_bilibili
How to construct a Visual Acuity Chart?
Snellen chart, Optometry, Visual Acuity Testing