A distance visual acuity chart incorporating some new design features
G. Strong and G. C. Woo
Standardized visual acuity assessments are possible when consideration is
given to legibility, acuity row legibility, letter spacing, optotype, row
arrangement, and letter size gradation. The relative optotype legibilities
reported by Sloan were verified experimentally under simulated conditions
of optical defocus. Acuity row component letters were selected to equalize
aggregate row legibilities and were arranged to minimize contaminative
sequencing dependency. We describe a new acuity chart format with vertical
acuity row presentations to eliminate bias from previous reading
experience, and testing procedures using this chart.
