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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 paraments

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.

How do I read my contact lens prescription?

Your contact lens prescription will contain the general parameters we listed earlier in addition to a Base Curve (BC) and a Diameter (DIA). Your BC and DIA information is necessary when placing an order for contact lenses as these values help ensure a proper fit on your cornea and total eye surface to ensure comfort and encourage eye health including proper oxygen to your eyes.

If you are refilling a contact lens prescription, you can look to the packaging that your current lenses came from. The information should be listed on the side of the box.