How to measure PD (Pupil Distance)

Your pupillary distance, or PD, is the distance between the centers of your pupils in millimeters (mm).
This measurement is necessary to ensure the correct positioning of the TTL loupes.
Because loupes are only used to view close objects, the PD you need for Loupes is called Near PD. Near PD is normally 2-3mm smaller than your regular PD. Make sure your optician is aware of this when you request your PD.
You have several ways to obtain Pupilary Distance, but we strongly recommend having your PD 
measured by a professional:

  •  If you purchased glasses before, contact the store you bought the glasses from and ask them for NEAR PD(recommended)
  •  Go to a local eyewear store or optometrist office and get your NEAR PD measured. Most will only charge approximately $5 for measuringyour NEAR PD. 
  •  Contact your optometrist for your NEAR PD(recommended)