How To Measure Your PD
What is Pupillary Distance
Pupillary distance (PD) measures the space between the pupils of your eyes
Why is it important
It ensures that you are looking through the optical center of the lenses
How to Measure
Just look straight, and use a ruler to measure
It's better to ask your family or friend to help measuring.
Please measure several times to get more accurate value.
As a reference:
Normal PD range for adult: 58 - 68 mm
Normal PD range for kids: 42 - 52 mm