| Description | This translucent eye chart uses Sloan optotypes for accurate testing. Each optotype has been calibrated for size, difficulty, threshold blur, and dimension. Each line is arranged equally. This eye test also includes two smaller groups for repetitive | The charts come as a set of two panels (21x24inches, 53x60cm) each with a high contrast chart one side and a low contrast chart (18% Weber or 10% Michelson) on the other. The optotype set is the family of ten British Standard (1968) 5x4 non-serifed |