Understanding Your Eyeglass Prescription
Your eyeglass prescription is a map of exactly how your eyes see the world. When you walk out of Vision Palace Optical on Avenue U after your eye exam, that little slip of paper in your hand contains precise measurements that tell an optician how to craft your glasses so you can see clearly. But unless you know what the letters and numbers mean, it just looks like a code. Here's what you're actually reading.
What Each Line on Your Prescription Means
Your prescription has two main sections: one for your right eye (OD, which stands for oculus dexter) and one for your left eye (OS, which stands for oculus sinister). Most people's eyes have different prescriptions, sometimes by a lot. Don't be surprised if they don't match.
Each eye's prescription includes three main values. The first is sphere (SPH), measured in diopters, which corrects whether you're nearsighted or farsighted. A minus sign (-) means you're nearsighted and have trouble seeing far away. A plus sign (+) means you're farsighted and have trouble seeing up close. The bigger the number, the stronger the correction.
The second value is cylinder (CYL), also in diopters. This corrects astigmatism, which is a blurry or distorted vision at all distances caused by an irregular cornea shape. Not everyone has astigmatism, so this line might be blank or say "0.00." If you do have it, you'll also see a third number called axis, which ranges from 0 to 180 degrees. The axis tells the optician exactly which direction to position the cylindrical correction on your lens so it lines up with your eye's irregular shape.
Additional Numbers You Might See
Some prescriptions include add power, which is an extra magnification for reading or close work. You'll see this on bifocal or progressive prescriptions, especially for people over 40. The add power is usually a small plus number (like +1.50 or +2.00) that makes small text clearer without taking off your glasses.
You might also see prism and base, which correct double vision or eye alignment issues. These are less common and used only when your eyes don't track together perfectly. If prism is on your prescription, that's something Dr. Shlivko or Dr. Sheyko will have discussed with you specifically during your exam at our office on Avenue U.
Many prescriptions also note your pupillary distance (PD), which is the distance between the centers of your pupils, measured in millimeters. This number matters a lot when glasses are made because the optical center of each lens needs to sit exactly in front of your pupil. An accurate PD is especially important for stronger prescriptions or progressive lenses. We measure PD carefully here in Sheepshead Bay as part of your complete exam.
Why the Numbers Matter for Your Vision
According to the American Academy of Ophthalmology, even small differences in these numbers can noticeably affect how clearly you see. A difference of 0.25 diopters in your sphere might not sound like much, but your eyes notice it. That's why precision matters when your glasses are made.
If your prescription changes year to year, that's normal. Your vision can shift for all kinds of reasons: age, eye strain from screens, seasonal dry eye in Brooklyn's variable weather, or just the natural aging of your eye. That's why we recommend a thorough exam at least every two years, or annually if you're over 50 or have conditions like dry eye or diabetes.
Never assume your old prescription will work in new glasses. Prescriptions expire. In New York, a glasses prescription is typically valid for two years, but if a lot of time has passed, your vision may have changed enough that you need a fresh exam. And if you order glasses online using an old prescription, you could end up with glasses that don't correct your vision the way they should.
How Brooklyn Patients Can Use Their Prescription
Once you have your prescription, you can use it at any eyewear retailer or optician in Brooklyn. Some people get their glasses made at the same place they get their exam. Others take their prescription to a different frame shop. Either way, the numbers and measurements stay the same.
If you're unsure about any part of your prescription, or if you get your glasses made somewhere else and they don't feel quite right, bring them back to Vision Palace Optical. We can check whether the glasses were made correctly according to your prescription, and we can verify that the PD and optical centers are positioned right. Sometimes a simple adjustment or re-centering fixes the whole problem.
Frequently Asked Questions
What does a minus sign mean on my prescription?
A minus sign on the sphere line means you're nearsighted, so you see close objects clearly but distant objects are blurry. This is the most common type of refractive error in Brooklyn and across the U.S.
Why are my eyes so different from each other?
It's completely normal for each eye to have a different prescription. Your right eye and left eye developed with slightly different shapes, and that affects how light focuses on the retina. As long as both measurements are reasonably close, your brain blends the two images together and you see normally.
Can I use my glasses prescription to order contacts?
No. A contact lens prescription is different from a glasses prescription because contacts sit directly on your eye instead of in front of it. You need a separate contact lens exam and fitting to get the right measurements for contacts. We offer contact lens fittings right here at our Avenue U office.
What if my prescription has a prism?
Prism corrects double vision or eye alignment problems. If Dr. Shlivko or Dr. Sheyko prescribed prism, it's important that your glasses are made exactly as specified. Prism glasses need precise centering and can't usually be made by just any eyewear shop. Bring your prescription to an experienced optician who understands prism correction.
How often does my prescription change?
For most adults in Brooklyn, prescriptions stay fairly stable year to year. But they can shift due to age, eye strain, dry eye, or other factors. That's why we recommend regular eye exams at least every two years, and annually if you're over 50 or have certain eye conditions.
Why does the add power on my bifocal prescription look so small?
The add power is the extra magnification for reading, and it's usually only +1.00 to +3.00 diopters. It looks small because it's an adjustment on top of your main prescription, not a separate full correction. For example, if your sphere is -3.00 and your add is +2.00, you're reading through lenses that effectively become -1.00 for close work.
What to Do With Your Prescription After Your Exam
Keep your prescription in a safe place. Many people take a photo of it with their phone or store a copy in their email so they always have it when they need it. If you're traveling outside Brooklyn or ordering glasses online, you'll need to reference it.
Remember that our office on Avenue U has your complete eye exam file. If you lose your prescription slip or it gets worn out, call us at (718) 998-8400 and we can print you a new copy. We're open Monday through Saturday, so it's easy to stop by on your lunch break or after work in Sheepshead Bay.
If anything on your prescription confuses you, ask us to explain it. Vision Palace Optical has been serving Brooklyn families and immigrants from all backgrounds for over 30 years. We speak English, Russian, and Spanish, and we never rush through explanations. Your vision is too important to leave anything uncertain.
References
Book your eye exam at Vision Palace Optical and get a complete explanation of your prescription, book through Zocdoc, get in touch, or call us at (718) 998-8400. We're at 1723 Avenue U in Brooklyn, open Monday through Saturday.