Correlation of Optotypes with the Landolt Ring—A Fresh Look at the Comparability of Optotypes

  title={Correlation of Optotypes with the Landolt Ring—A Fresh Look at the Comparability of Optotypes},
  author={Wolfgang Grimm and Bernhard Rassow and Wolfgang Wesemann and Konrad Saur and Rudolf Hilz},
  journal={Optometry and Vision Science},
The legibility of three selected sets of optotypes: (1) letters; (2) Snellen E; and (3) KOLT test have been compared to the Landolt ring in a study based on the German Standard DIN 58220, Part 2 and the International Standard ISO 8597. The letters were printed in the standard typeface used on German street signs (sans serif Linear-Antiqua, Typeface B). The main results are: 1. A set of letters can be selected in such a way that the differences in legibility displayed between different letters… Expand
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