This "revised" eye chart incorporates a slight change in the difficulty score for each of the ten SLOAN letters derived from the best corrected visual acuity examinations of 7,420 eyes during the ETDRS study. The "original charts" difficulty scores were derived from the examination of 234 eyes.
For vision testing at 3 meters (10 ft.)
Acuity range 30M to 1.5M (20/200, 6/60 to 20/10, 6/3 equiv.)
Measures 62 X 65 cm (24.5 X 25.5 in.)
Fits ETDRS Illuminator Cabinet CAT. NO. 2425
Can also be wall mounted
ETDRS "2000" Series eye tests are used by and supported by the National Eye Institute (NEI). They are used in Low Vision Evaluations, Clinical Testing, and Clinical Research. They are also supported by the FDA. ETDRS vision test charts have become the world standard in vision testing due to their precise calibration. Proportional spacing, attention to equality in difficulty from line to line and optotype to optotype, and geometric progression are what make the ETDRS charts so reliable and trusted worldwide.
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