HOW TO UNDERSTAND YOUR PRESCRIPTION

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What is it Common layouts Prescription terms Get prescription

2. MOST COMMON LAYOUTS

Here's a look at a sample eyeglass prescription and a walk-through on how to read it. Below are examples of alternative prescription formats. Look through these to get a general feel, but don't worry if yours still looks different – so long it has all the essential information, you are good to go!

Each optometrist or ophthalmologist will have their own format for writing a prescription, so yours may not look exactly like the one pictured, but that's nothing to worry about. The essential information should be there, and it should always begin with your full name.

(Oculus Dexter – Latin abbreviation) means the right eye.

(Oculus sinister) means the left eye.

SPH

Sphere this indicates the amount of lens power measured in diopters (in 0.25 steps)

(-)

Stands for near-sighted (difficult to see things that are far away).

(+)

Stands for far-sighted (difficult to see things at close distances).

Pupillary distance (PD): The distance between the center of each pupil, measured in millimeters. It tells the optician where to put the optical center on each lens

Cyl/CYL

Cylinder. Only for astigmatism. The amount of astigmatism that is caused by an irregularly shaped cornea, measured in diopters (in 0,25 steps). If there is no cylinder, your eyes are perfectly spherical.

ACH/A

Axis only for astigmatism. The direction of astigmatism, measured in degrees (0-180).

ADD

Addition. If you are over 40, you are likely to see ADD on your prescription – that's the difference between near and far values. Often the same for both eyes. For multifocal glasses.

Prism

Often prescribed when your eyes don't work well as a pair. Not common.

Base

Tells the opticians where to put the prism in your lenses.