This revised eye chart incorporates a slight change in the difficulty score for each of the ten SLOAN letters derived from the best corrected visual acuity examinations of 7,420 eyes during the ETDRS study.
Can be wall-mounted.
ETDRS 2000 Series charts utilize a geometric progression from line to line. Each optotype on the chart is proportionally spaced. By using these types of progression and spacing the chart becomes balanced and equal. This give the patient a well calibrated test that can be reused, relied on, and trusted.