What’s The Story About Pupillary Distance On My Prescription Glasses?
This has become a topic of conversation in our industry. We will do our best to tread lightly, but we want to share what we believe is true about pupillary distance.
Why is this a hot topic?
Have you ever asked for your pupillary distance measurement at your local eyeglass shop or optometrist office, and got the stink eye?
This question is a sore spot for us because it makes us feel like you don’t want to do business with us, which by the way you have every right to shop around to where you like. We know that you mean well by asking us this innocent question.
What is Pupillary Distance?
This refers to the measurement between the center of your pupils (aka the dark round centre part of your eye).
Back in the day, we’re talking 1900s, this was the only real measurement opticals would take to make your prescription into your glasses. It still works to this day, but your vision is not fully optimized. Technology has advanced, hallelujah!, and we now use up to 5 measurements to make your glasses
Why more measurements?
The answer is welcome to the world of “Digital Surface Freeform” technology.
We now use modern computers as part of the process of edging your prescription into your lenses. The advantage of using computers to do up your lenses is because we can enter 100x more data points on the lens surface, which makes your prescription more customized to your frame and where they naturally rest on your face. This makes your prescription more accurate so you end up seeing HD instead of 360-480p (maybe not quite 4K yet).
Using digitally surfaced lenses and measurements on top of pupillary distance is even more critical for those who have high/thick prescriptions, astigmatism, and wear progressive/multifocal lenses. It’s important to get your PDs properly measured with these wearers because if we’re off in the measurement then you’ll experience headaches, blurred vision, and may feel off balance.
So, can I have my Pupillary Distance?
No… at least not at Respect Eyecare.
We believe in offering everyone that comes to Respect the best possible vision, and that we would be doing a disservice otherwise. We believe it creates an awkward situation if we offer your pupillary distance measurement but then you experience problems seeing well with your new specs from X, Y, Z Optical? Were the optical centre, pantoscopic tilt, faceform wrap, segment height and vertex distance included in the measurements? It makes it challenging for us to pinpoint the solution.
We use to get guests coming back telling us there must be something off with the prescription we gave them or they’re not seeing well with their glasses made X, Y, Z Optical. In our experience, 9/10 cases there’s no change to the glasses prescription. That’s because we now know that it takes more than just one measurement to get your glasses bang on.
Conventional lenses that only require a Pupillary Distance measurement work, you just may not be seeing as clear as you can be.
About The Author Dr. Steve received his Doctor of Optometry at the University of Waterloo. He serves as the owner and full-time eye doctor of Inglewood and Ramsay at Respect Eyecare. His special interest is in contact lenses and dry eye syndrome.