Pupillary distance is the space — measured in millimeters (mm) — from the center of one pupil to another. When you need glasses, an optometrist or an optician will measure this distance to make sure ...

The pupillary distance (PD) measurement is a requirement for people who want to purchase eyeglasses. Here, find out how to measure your PD using a mirror and a ruler. Share on Pinterest Some eyewear ...

Pupillary distance helps center your eyeglasses prescription. Your eyeglasses provider normally measures it for you, but you won’t find it on your prescription. If you order glasses online, you’ll ...

The abbreviations and numbers on your eyeglass prescription describe the type and strength of lenses you need, and the degree of nearsightedness, farsightedness, or astigmatism in each of your eyes.