Did you know that an error of only 2mm can lead to a loss of more than 40% of your clear vision field?
PD, or pupillary distance, refers to the distance in millimeters between the center of one pupil to the center of the other. It is used to determine where the optical center of the lens should be placed on your glasses that need to line up over the center of the pupil. Having a correct measurement of your PD on your glasses prescription ensures that you’re looking through the ideal precise placement spot (Optical Center) in your lenses.
There are two ways to measure the distance: single PD and dual PD.
Single PD will measure the distance between the center of one pupil to the other while dual PD consists of two numbers and is the distance between the centers of each pupil to the bridge of the nose.
For Example, The average adult's single PD is between 54-74 mm; kids' are between 43-58 mm but a fun fact is that most of us are not symmetrical and therefore your dual PD will be most likely not even 32/30.
On your next visit with Eyecare Leaders, be sure to ask about your PD and discover how symmetrical you are :-).