Receiving your eye prescription can sometimes feel like reading a secret code. Between the Latin abbreviations and the various columns of numbers, it is easy to feel lost. Understanding what these figures mean can help you make better decisions about your frames, lenses, and overall eye health.

The Abbreviations

The most common abbreviations are derived from Latin, which is standard across the optical industry:

• OD (Oculus Dexter): Simply put, this is your Right Eye.
• OS (Oculus Sinister): This refers to your Left Eye.
• OU (Oculus Uterque): You may see this if the prescription applies to Both Eyes.

The Numbers

• SPH (Sphere): This is the most common part of the prescription. A negative sign (-) indicates you are nearsighted (myopic), while a positive sign (+) indicates you are farsighted (hyperopic). The higher the number, the stronger the lens.
• CYL (Cylinder) & AXIS: If you have an astigmatism, your cornea is shaped more like a football than a basketball. These numbers describe the strength and the orientation of the lens needed to correct that shape.
• ADD (Addition): This is the additional magnifying power used for reading. You will typically see this on prescriptions for people over 40 who require help with close-up tasks like reading a book or a smartphone.

Does Your Prescription Change?

It is completely normal for your prescription to change over time. Factors like aging, digital device usage, and general health can all impact your vision. This is why annual exams at El-Amin Ophthalmic Center are so important; they ensure your eyewear is always optimized for your current needs.

Next Steps

Instead of trying to decipher these numbers on your own, bring your latest prescription to us. We will ensure your new lenses provide the comfort and clarity you deserve.