Q: How do I determine the Pupillary Distance?
A: Dear, we would like to tell you that "PD" stand for Pupillary Distance and is a required measurement when making eyeglasses. When you have finished an ophthalmic examination or vision test, doctors will write your PD on the prescription. Generally, there are two different PD values. One of them is your basic PD, which is the distance in MM between the centers of your pupils. The other is mono PDs(PD for each eye), two numbers around 30mm. If you don’t have any PD values on the prescription, you have rights to contact your doctor/optometrist to get your accurate PD value.Or you can measure it yourself with a millimeter ruler. Follow these simple steps: 1.) Rest a mm ruler on the bridge of your nose just in front of your eyes. Look straight ahead and line up the 0mm marker with the center or one pupil.2.) Read the ruler in a mirror, or have someone at the same height as you read it.3.) The mark that lands in the center of the other eye is your Pupillary Distance. 4.) Repeat these steps 2-3 times to make sure your results are accurate.