What Is Pupil Distance (PD) ?

 (PD is also called Pupillary Distance and Inter-Pupillary Distance )

buying prescription eyeglasses online you have probably seen the term PD or pupil distance so what is (PD)?>>>The distance between the center of the pupil in one eye and the center of the pupil of your other eye.PD varies from person to person but once you are an adult, your PD does not change. Therefore, as an adult, if you have had it measured, then it will still be the same, even if your spectacle prescription has changed. Once you know your PD, you do not need to measure it every time you buy prescription glasses.PD is measured either during the eye test or when prescription glasses are ordered so it is best to make sure your PD is included in your eyeglasses prescription.