A Sloan Letter ETDRS contrast chart at 2.5% contrast and proportionally spaced (logMAR) lines; line sizes range from 10/100 to 10/5 (3/30 to 3/1.5 equivalent) with letter size, 20 foot, 6 meter, LogMar, and decimal notations. These charts fit in the ESV3000™ ETDRS Standardized Viewer and ESC2000™ Illuminated Cabinet.
Dimensions: Height 24.5" x Width 25.5" (62 cm x 65 cm).
Testing distance: 10 feet/3 meters.