Two smaller groups 4.8M to 1.2M for repetitive testing (20/32, 6/9.5 to 20/8, 6/2.4 equiv.).
Can be wall-mounted.
Useful for testing sight in multiple languages. Also helpful for testing preliterate and illiterate patients.
Traditional design and proportional spacing help insure accurate testing.
PV Numbers are calibrated comparatively to our Patti Pics series charts: on the basis of the 5×5 Snellen grid and calibrated for equal recognizability against Sloan letters. Even illiterate adults can often recognize numbers. Deaf or mute adults can indicate the number seen with simple finger signs.