How to read a prescription
How to read a prescription.
It's essential to understand how to read your eyeglass prescription. That's why we put together this guide to help you understand your prescription.
Glasses Prescription Definitions:
OD = Refers to the right eye.
OS = Refers to the left eye.
SPH = Sphere corrects nearsighted or farsighted vision.
A “plus” (+) sign in front of the number means you are farsighted.
A “minus” (-) sign means you are nearsighted.
Farsighted = Unable to see things clearly at a far distance.
Nearsighted = Unable to see things clearly unless they are relatively close to the eyes.
CYL = Cylinder combined with Axis shows that you have astigmatism.
Astigmatism = A misshaped cornea or lens of the eye that causes blurry vision.
PD = Pupillary Distance is the measurement of the distance between the pupils
The numbers = Represent diopters, the unit used to measure the correction, or focusing power, of the lens your eye requires.
ADD = The additional value is used for bifocal, progressive, and reading glasses that help correct presbyopia. It is also known as the magnification power.