Your Prescription Glasses: More Than Meet The Eye.
If your eyecare professional determines you need prescription lenses after an eye exam, you'll receive a prescription slip much like those you'd receive for a particular medication. But that's where the similarities end! Your personal prescription will provide data specific to your need for prescription eyeglasses as well as outline any recommendations your eyecare professional may have for more specialized lens products and treatments.
How To Read Your Prescription.
While not all eye doctors use the same abbreviations, here is a list of commonly used terms you'll often find on a slip for prescription lenses.
- O.D. stands for "Oculus Dexter", which is Latin for "right eye"
- O.S. stands for "Oculus Sinister," which is Latin for "left eye"
- D.V. "Distance vision" relates to far-sightedness – a condition where distant objects are seen clearly, yet objects close up are seen less clearly.
- N.V. "Near vision" relates to near-sightedness – a condition where near objects are seen clearly, yet objects in the distance are seen less clearly.
- SPH stands for "sphere", and corresponds to numbers that indicate the degree to which a patient is near-sighted or far-sighted
- CYL means "cylinder", and corresponds to numbers that indicate the amount of astigmatism present in a patient's eyes. Astigmatism is an eye condition resulting from an irregular curvature in the eye, causing mild, moderate or severe blurred vision.
- AXIS corresponds to numbers indicating the orientation of astigmatism in the eyes – how and where the irregular curvature occurs.
- PRISM is a prescription element that's added if your eyes need help either working more effectively together, or staying in proper alignment.
- PD stands for "Pupillary Distance", and measures the distance between your pupils (in millimeters). This measurement helps ensure your prescription is properly placed in your frames.
- Seg Height short for "Segment Height" – referring to the near portion or "segment" of the lens and how it aligns in the frame relative to your pupils. It is important when fitting multifocal (bifocal, trifocal or progressive) lenses to achieve optimum use of the reading portion.
The point is, while eyeglass lenses are prescribed to correct all kinds of vision problems, prescription lenses have come a long way – offering you the opportunity to truly customize your eyeglasses and make a statement about how you choose to look at the world.