What is PD and how to get it

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.

  1. If you purchased glasses before, contact the store you bought your glasses from and ask them for your NEAR PD(recommended)
  2. Go to a local eyewear store or optometrist office and get your NEAR PD measured. Most  will only charge approximately $5 for measuring your NEAR PD(recommended)  
  3. Contact your optometrist for your NEAR PD(recommended)
  4. Measure the PD yourself (not recommended)  If you decide to measure the PD yourself and it turned out to be not accurate, there will be a 50% remaking fee to remake another pair of TTLs for you

schultz dental loupes about pd

To measure your Pupillary Distance (PD):

Place a regular ruler on the bridge of your nose. Have a friend face you about arms length away. Have your friend measure the distance between the center of your pupils (your pupils are the black dots in the middle of your eyes). Or you can also measure the NEAR PD yourself simply by looking in the mirror. If you need your glasses on to do this, you can draw dots on the lenses where your pupils are (using a magic marker or highlighter); then take the glasses off and measure the distance between them.

Remember, the PD number is noted in millimeters. If your ruler has only inches, please click here to convert inches into millimeters. 

As a guideline:

Most adults' PD's are between 55-65mm. Most kids' PD's are between 42-54mm.