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"2000" Series Revised ETDRS Translucent Chart "1", Chart "2", and Chart "3"
The same standardized format as the Original Series charts accepted in studies sponsored by the National Eye Institute as well as all the other features and specifications described on the original ETDRS page. The 2000 Series Revised Charts incorporate a slight change in the difficulty score for each of the ten SLOAN letters derived from the best corrected visual acuity of 7,420 eyes during the ETDRS study. The Original Series Charts difficulty scores were derived from the examination of 234 eyes. The 2000 Series has the ultimate homogeneity with a balanced arrangement so that each of the ten SLOAN letters in the chart are represented at least once in every position across a line.
Charts measure 62 x 65cm (24.5 x 25.5 in.)
All charts fit ETDRS Illuminator Cabinet Cat. No. 2425 or can be wall mounted.
All charts have acuity range of 20/200 to 20/10, (6/60 to 6/3 equiv.)
4 meters - 40m to 2m
3 meters - 30m to 1.5m
2.5 meters - 25.2m to 1.2m
2 meters - 20m to 1m
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