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How do I read my glasses prescription?

Following an eye exam, your optician will provide you with a prescription. Your prescription will include the following general parameters:

OD – Right eye parameters

OS – Left Eye parameters

SPH – Sphere indicates the amount of lens power prescribed to you for nearsightedness or farsightedness

CYL & AXIS – CYL (Cylinder) and Axis information helps correct Astigmatism. Both parameters are required together.

ADD – This provides magnifying power for reading, progressive and bifocal lenses.

How do I read my glasses prescription?

In addition to the general parameters, your glasses prescription also requires a Pupillary Distance (PD). Your PD is the distance measured in millimeters between the centre of one pupil to the centre of your other pupil. You will need to provide both the general parameters and your PD when ordering glasses through Oyesum Optiks. You can obtained your PD through a doctor during an eye examination.