Home/Blog/What Do The Numbers In Your Vision Prescription Mean?
What Do The Numbers In Your Vision Prescription Mean?
Leaving your eye exam with an updated vision prescription feels great, but if you’ve ever taken a glance at the prescription itself, you might find yourself confused. Unlike prescriptions for medication or physical therapy, vision prescriptions rely on a good deal of industry jargon and metrics. We’ll break down the basics for you, here.
KEY TERMS TO UNDERSTAND EYE PRESCRIPTION MEANING OD/RE, OS/LE, AND OU
Your prescription will contain some of these abbreviations. OD refers to the Latin “oculus dexter,” or “right eye” (RE). OS refers to the Latin “oculus sinister,” or “left eye” (LE). If your prescription deals with both eyes, you might notice the abbreviation OU, which stands for the Latin “oculus uterque,” or “both eyes.”
SPHERE (SPH), CYLINDER (CYL), AND AXIS
If you need vision correction, you’re either…
Nearsighted: able to see up-close objects, yet not able to see objects that are far away
Farsighted: unable to see up-close, while distant objects are much more clearly visible
…or both. The sphere section of your prescription indicates how much correction is needed for either problem. If you’re nearsighted, you’ll notice a negative number. If you’re farsighted, you’ll see a positive number.
The cylinder section of your eyeglass prescription, on the other hand, indicates how much vision correction is needed for astigmatism, a common condition that causes blurred vision. If this section of your prescription is blank, it means that you have little, if any, astigmatism to correct. If this column includes a negative number, it indicates that you need vision correction for nearsighted astigmatism, while a positive number indicates farsighted astigmatism.
Similarly, the Axis measures the position of astigmatism, indicating precisely where correction is needed.
The numbers in your prescription refer to diopters, a unit that refers to the power of the lens. The larger the number, the larger the correction that’s needed. When you look over your prescription, if you see smaller values like +/- .25, you can see that this part of your vision needs some correction. Larger values like +/- 5, indicate that a good deal more correction is needed for this part of your vision.
GET YOUR EYES CHECKED ANNUALLY TO MEASURE CHANGES
Understanding your eye prescription meaning empowers you to take good care of your eyes along with your providers. My Eyelab keeps track of customers’ prescriptions from year to year so we can measure changes in their eyesight. When you understand your prescription, you’ll also be able to notice trends and changes in your vision. If you notice, for instance, that your nearsightedness is worsening, you’ll know that this is something to ask about at your next eye exam.
WE’RE ALWAYS HAPPY TO ANSWER YOUR QUESTIONS
If you have further questions about your prescription, let us know! My Eyelab provides some of the most innovative eye exams in the industry, and we’re always happy to review the results with you in detail. In addition to revealing the vision correction you’ll need, our exams also identify a wide range of eye diseases, so our customers can be sure we’ll spot any signs of trouble.