ETEDRS-Originalserie 4 m – SLOAN-Buchstaben Tafel „R“Translucent LogMAR standard chart for 4 m distance. VA: from 0. 10 to 2. 00, Format: 62 cm x 65 cm Good Lite: 500013 ETDRS eye chart Original series chart R with proportionally spaced (geometric progression) lines; line sizes range from 20 200 to 20 10 (6 60 to 6 3) equivalent. Standardized format used in National Eye Institute clinical studies and in low vision evaluations that require accurate and repeatable visual acuity measurements. Chart