PD stands for pupillary distance - the distance between your pupils. It is usually 60-70 millimeters. This measurement is crucial for us to line your RX up correctly. Anywhere that has made lenses for you in the past has this measurement on file. You should be able to obtain this simply by calling them.
PD and how to measure (PD) is the distance between the centers of the pupil in each eye, usually measured in millimeters. This measurement helps to properly align prescription lenses to the center of the pupils. You can ask your optician to measure this for you or you can measure it yourself. To accurately measure the PD, use a ruler and a mirror or ask a friend fro assistance. Set a millimeter ruler on the bridge of your nose and align the Zero - 0 mark with center of your left pupil. Looking straight ahead, use the ruler to measure the distance between the center of your left pupil and the center of your right pupil. The measurement should be taken twice for accuracy.