In optical dispensing, what does "PD" represent?

In optical dispensing, "PD" stands for Pupillary Distance. This measurement is critical for ensuring that the optical center of the lenses is perfectly aligned with the pupils of the eyes when glasses are worn. Proper alignment ensures optimal vision and comfort for the wearer, as misalignment can lead to visual distortions or discomfort.

The pupillary distance is typically measured in millimeters and can be determined through various methods, such as using a ruler or specialized tools during the eye exam or fitting process. It plays a significant role in crafting prescription eyewear, especially in multifocal lenses, where precision in placement of the lenses according to the user's eye position is even more crucial.

Understanding PD helps optical professionals provide the best service and product quality to their clients, ultimately enhancing their visual experience.