If you wear or have been told that you need eyeglasses, at some point, a specialist may show you your corrective lens prescription. This collection of numbers can look confusing at first but is surprisingly simple once you understand the basic information they describe. Here's what you should know about the information contained in a prescription and how to understand it.

What Do the Numbers in a Prescription Mean?

An eyeglass prescription consists of several numbers that indicate the corrective power of the lenses. The prescription is written in diopters, a unit used to measure a lens’ refractive power.

The first number is the sphere power, which represents the amount of power needed to correct either nearsightedness or farsightedness. The second number is the cylindrical power, which describes the amount of power needed to correct astigmatism. The last number is the axis, which indicates the exact orientation of the cylindrical power. Together, these three numbers indicate the exact power and orientation of the lenses needed to correct a person's vision.

How Can You Read Your Prescription?

Reading an eyeglasses prescription is fairly straightforward. First, you’ll need to find the sphere (SPH) value, which will tell you the strength of the lenses. A positive number means you’re nearsighted and need a concave lens, and a negative number means you’re farsighted and need a convex lens.

Next, look for the cylinder (CYL) value, which tells you the amount of astigmatism correction required. Then, find the axis (AX), which tells you the orientation of the astigmatism correction. Finally, look for the add (ADD) value, which is the additional magnification required for reading glasses. Once you have all of these values, you can provide them to your optometrist or optician to order the correct lenses for your glasses.

If you're looking for more expert eye care advice, new eyeglasses, or simply a routine eye exam, get in touch with Russellville Eye Clinic PA. Serving patients throughout Pope County, AR, the staff at this eye health center can help with everything from providing new prescriptions to screening services and treatment for a wide range of eye health conditions. Call (479) 968-7302 to schedule an appointment, and visit them online to learn more about their services.