Each Prescription is always read left to right starting with your RIGHT Eye prescription strength.

OD (right eye)   OS (left eye)

SPH: This is the Spherical power of your prescription. It corrects either the distance or reading strength of your prescription.

CYL: This is the Cylindrical power of your prescription, also known as your Astigmatism. This power is always measured in MINUS form.

Axis: Your Prescription Axis tells us what direction we need to position your CYL (astigmatism) power in your lenses. Simply stated: It describes the position of your Astigmatism. All axis angles are measured in degrees from 1 to 180.

ADD: Your ADD power is also known as your reading power. When correction for up close is needed, we combine your distance power with your reading power to make your prescription "Readers" Please note on your order if your prescription is for reading only.

PD: Your PD, also known as your pupil distance is the distance between both of your pupils. Your PD is always measured in millimeters. We use this measurement to center your eyeglass lens prescription in your frames so you are seeing through the clearest part of the lens. If your PD was not provided to you on your prescription, you can either stop by our Flagship location (JJ Optical in Regina, SK) or you can follow the instructional video below to take your own measurement. 

Prism: Prism correction is used to correct Misaligned eyes, also know as "lazy eyes" Due to the complex nature of Prism, we do not offer it online. Please visit our flagship store for in-store assistance.

Jimmy Mac How to Read Prescription