20 ft: COH (9 Line) Chart

(9" x 14") Sloan optotype chart for vision testing at 20 feet. Features two smaller groups 20/25 to 20/12.5 for repetitive eye testing. May be wall mounted or used with illuminated cabinets (66003, 66004, 66016, 66090).

The Sloan optotypes were developed on the same basis as Snellen optotypes. Sloan optotypes do not use serifs however, but do use a logarithmic geometric progression.