Pupillary Distance: Why This Measurement Matters

Pupillary distance (PD) pertains to the distance between your pupils. You might not see it on your eye prescription, but it is essential to the comfort of your new glasses. If this measurement is incorrect, you could suffer from blurred vision, eye strain and headaches.  

Keep reading to learn more about the importance of accurate pupillary distance.

Good Eyeglass Fit

The primary purpose of PD is for eyeglass fitting. It can be used to assess areas of your vision, but you don’t see it on your prescription because it doesn’t affect your vision treatment management. Your opticians might measure your PD using a pupillometer or a digital PD meter. They will hold the tool up to your face and make necessary adjustments to achieve the right distance.  

To see as clearly and comfortably as possible, your lenses must sit directly in front of your pupil. Your prescription’s clearest part is the center, and lining it up with your pupil will help you see clearly and reduce the likelihood of eye strain. PD could be different depending on the eyeglasses you prefer. 

Testing Stereo Acuity and Near-Point Convergence

Your eye doctor refers to your depth perception as stereo acuity. Each of your eyes sees a different image, but your brain pieces them together to create a three-dimensional object. PD allows specialists to understand the difference in your field of vision between your left and right eyes. 

Near-point convergence happens when your eyes focus on a nearby object. To test it, your doctor might bring a pen or another item to your nose and see how your eyes move together to focus. As your eyes converge, your pupillary distance shortens, so your eye specialist might assess changes in your PD.

At Insight Vision Center Optometry, we are committed to helping meet your vision and eye care needs. We offer prescription glasses, specialty contact lenses, dry eye treatment and more! Call us at (714) 486-3315, or fill out our contact form to learn more about our services.