Ordering prescription glasses online at phaneo is fast and easy. To custom-craft your lenses in our integrated optical laboratory, we need two critical pieces of information: your Eyeglass Prescription and your Pupillary Distance (PD). Here is our simple guide to understanding both.
1. How to Read Your Eyeglass Prescription
An eyeglass prescription consists of numbers and abbreviations. Below is a breakdown of the standard terms used by your optometrist:
| Abbreviation | Full Name | What it Means |
|---|---|---|
| OD | Oculus Dexter | Parameters for your Right Eye. |
| OS | Oculus Sinister | Parameters for your Left Eye. |
| SPH (Sphere) | Sphere | The strength of your correction. A minus (-) sign indicates nearsightedness; a plus (+) sign indicates farsightedness. |
| CYL (Cylinder) | Cylinder | The amount of lens power needed to correct astigmatism. If you have no astigmatism, this column will be blank or say "SPH" or "DS". |
| AXIS | Axis | The direction of your astigmatism (measured in degrees from 1 to 180). Required only if you have a CYL value. |
| ADD | Addition | Additional magnifying power added to the bottom part of progressive or bifocal lenses. |
2. How to Measure Your Pupillary Distance (PD)
Your Pupillary Distance (PD) is the distance (measured in millimeters) between the centers of your pupils. It ensures the optical center of your lenses sits perfectly in front of your eyes. If your doctor did not write your PD on your prescription, you can measure it yourself at home:
Stand approximately 8 inches (20 cm) away from a well-lit mirror. Hold a millimeter ruler flat against your browline.
Close your right eye, and align the "0 mm" mark of the ruler precisely with the center of your left pupil.
Look straight ahead. Close your left eye and open your right eye. Read the millimeter line that aligns directly with the center of your right pupil.
Repeat this process 2 to 3 times to ensure a consistent, accurate measurement. For most adults, a standard PD falls between 54mm and 74mm.
Need Help or Want Us to Handle It?
If you find this confusing, don't worry! You can simply upload a picture of your physical prescription slip during the checkout process, and our certified in-house lab technicians will manually verify and extract all the details for you.
Email your prescription photos to: support@phaneostore.com