2.4K views · 28 reactions | Pupillary Distance (PD) is the distance, in millimeters, between the center of one pupil to the center of the other. The PD is needed to manufacture your eyeglasses because it determines the exact optical center of the lens, which is the point where you look through the lens. Note: the average PD is between 54 and 78mm. | Zeelool | Facebook

3.4K views | Did you know Pupillary Distance (PD) is used to help center a prescription accurately in your glasses? Learn how you can measure your own PD in 5 simple steps.  | Clearly | Facebook