PUPILLARY DISTANCE
PD:
Measurement from Pupil Center to Pupil Center, in Millimeters
How to Measure PD
PD, (Pupillary Distance), refers to the measurement of distance from the center of one pupil to the center of the other pupil. The distance is measured with a ruler and always in millimeters.
Ask your Eye Doctor to include your PD Measurement on your prescription to get the most accurate reading or carefully use a ruler to measure from one pupil center to the other.
Look in a mirror and line up a ruler on the millimeter side between pupil centers.
Double-check that the ruler "O" mark is lined up exactly at the center of the first pupil.
Measure the exact distance in mm to the center of your other eye. That is your PD!
