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How To Read Your Eye Prescription

After your visit to a Calgary optometrist, you may get a prescription for eye correction. While you may know your vision needs work, these prescriptions can be hard to read for other reasons! To decipher the numbers and terms here is a quick and handy guide on how to read your eye prescription.

Understand the Headings in Eye Prescription First

The first thing you will see on your eye prescription from a Calgary optometrist is that there are different sections. Usually, these headings are two-letter abbreviations like OS, OD and OU. These abbreviations are short for the Latin terms oculus sinister, oculus dextrus and oculus uterque. These sound advanced, but their meanings are actually simple.

Oculus sinister (OS) stands for your left eye while oculus dextrus (OD) represents your right eye. Anything under the label oculus uterque (OU) is indicative of both eyes.

Examine the Numbers Second

Under each heading, you should see numbers. These numbers represent the amount of correction. Larger numbers indicate that more correction is needed.

There should also be a plus or minus sign in front of the numbers. This sign indicates if you are nearsighted or farsighted. If the number is a plus, then you are farsighted. A minus sign, by contrast, indicates nearsightedness. Specifically, the numbers are measurements of focusing power. Your Calgary optometrist may refer to this as a diopter. It denotes what lens you need.

Eye Glasses Vision Perscription

Consider Additional Commentary Last

If there is an additional notation on your eye prescription, then it probably relates to astigmatism. Astigmatism will appear with three numbers. These numbers are measurements for spherical, cylinder, and axis.

Spherical numbers indicate the degree of your correction. Your cylinder number is the extent of your astigmatism. The axis number shows the directionality of your astigmatism.

Astigmatism refers to the shape of your eye, so it is important for precise measurements to be included in prescriptions.

When you need a Calgary optometrist, trust the experts at Urban Eyecare. Visit us at one of our two Calgary locations for a comprehensive eye exam for you or your children. We are happy to help! Call us today!

Sunridge Location (403) 280-8330

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