JUN 14

Prescription Limits and Lens Curvature

Prescription lenses are a fairly complicated business, and none are more complex than curved lenses for wraparound frames.

Lens Curvature and the Limits of Prescription Glasses

Most people think that prescription glasses are an exact science, and in some ways they aren’t wrong. The numbers written on your prescription are not a guideline; there are strict tolerances regarding how precise a prescription has to be.

On the other hand, two people with the same prescription may feel completely differently about the same pair of glasses. One might feel that the prescription is perfect, while the other is so uncomfortable that he or she can’t stand to wear the glasses for more than a few minutes. These are extremes, though the example is not an exaggeration.sunglasses, eyeglasses, prescription sunglasses, prescription eyeglasses

When ordering prescription glasses in a wraparound frame, this disparity is acutely magnified. Prescription wraparound glasses (such as sunglasses frames, motorcycle glasses, and safety glasses) must be made with special and deliberate care to ensure that the patient can see and feel comfortable while wearing the glasses. Even then, there are a select few people who cannot get used to wearing prescription wraparound glasses, just as there are people who cannot adapt to progressive bifocals.

Here are good guidelines to follow when ordering prescription wraparound glasses online:

  • Prescription power in this context is defined for each eye seperately. It is measured by adding the sphere and cylinder powers together. In example, -2.00 sphere and -2.25 cylinder in your right eye would equal a -4.25 power. On the same token, a +2.00 sphere with the same cylinder would add to only -0.25. Axis is not factored here.
  • A lens’s “base curve” is defined as the amount of curvature of the front of the lens. Typically, the lens front is not altered during the prescription making process. All the power of the lens is worked into its back: the side facing your eyes.
  • Higher base curves mean more curved lenses. A base curve of zero is as flat as glass on the front, whereas a base curve of 8 is the standard for many especially curved wraparound lenses in sports glasses.
  • If you are ordering prescription glasses in a wraparound frame, you can expect that the prescription will have to be made into a curved lens of base 6 or 8. There are limits to the power of a prescription in this base curve. If your total prescription power in one or both of your eyes adds to anywhere outside the range of -4.00 to +3.00, you are at special risk of not adapting to wraparound lenses.

  • Prescriptions with a power outside the range of -6.00 and +4.00 either cannot physically be done or are barely able to be done in a high base curve, depending on your prescription. The end result is, even if the prescription is made, it is highly unlikely that you will be able to adjust to the new lenses.
  • People with prescriptions that have high cylinder (outside the range of -2.00 to +2.00) generally cannot adjust to a wraparound frame.
  • Those who have prism are also at risk for being unadaptable to wraparound frames. Also, in general, prism causes the eyeglasses themselves to look strange or bad in a wraparound.
  • If you have never had a wraparound prescription before and are on the border of one of these limits, it is good to be cautious. You may not be able to adjust to a wraparound prescription.

If you are curious about whether your prescription will work in a wraparound frame, it is a good idea to call us so we can have a conversation about it. We will be able to tell you whether or not wraparound style prescription glasses are right for you.

Occasionally, even people who have a very light prescription find that wraparound glasses do not work for them. This is not a matter of preference of lack of flexibility; it is simply an inexplicable issue that occurs for select individuals. There are no solid explanations, but it may have something to do with your ocular muscles or even something with the processing of your vision that occurs inside your brain. Whatever the reason, some people just aren’t right for wraparounds.

There are other options if you want a wraparound prescription in a curved frame and your prescription is too high. Give us a call or leave a comment if you’d like to talk about this. We hope this sheds some light on prescriptions in wraparound frames, and thanks for reading!

  1. Steve says:

    Well I got my new glasses, the plus 16 in one eye and 15.5 in the other bifocals. Long story but I been looking through terrible glasses for 6 years, last year was through the new ones that had a curve on the back thinner at the edges caused smokey blur, narrow vision. Anyway the new ones are like my old, old, ones but smaller and still not clear to the edge, but it’s so weird to see again after all that time. Please complain and tell these corporations to make aspheric plus 16 lenses. (or for any high prescription would be IS a superior lens.)

  2. Steve says:

    I never had lenticular lenses. I was born with defective eyes, the lenses that work were made by Sola a plus 16 curve with bifocal, Then Zuise came along and bought it and they destroyed the molds, Why ? because the industry wants everyone to get cataract surgery. I am so tired of hearing that a stupid lens can’t be made in this day in age, I am not a car that needs discontinued car parts. Plus I am tired of everyone thinking on how bad my eyes are when in fact I can do most every function in life, and have used telescopes, microscopes,frisbee golf, driving. So I am left with labs trying to struggle all because of corporate greed, more or less. I just want people to know what is going on.

    • rxsafety says:

      I understand if you need anything please let us know we would be more than happy to work with you on a new pair of glasses.

  3. Steve says:

    I have a plus 16 curve lens that have been made 40 plus years ago and worked very good. My natural lenses are still in my eye and I never had lenticular lenses. However the lens companies have abandoned me or anyone like me, Ya really great technological world with computers and lasers and they can’t even make a friggen lens for us people who NEED glasses. Most of you can see without glasses and now they turned it into a market for people who go for cosmetics, sickening. Heck why make bandaids anymore .

    • rxsafety says:

      Steve,

      Please call customer service and ask for Ryan we can still get lenticular lenses. 888-440-9797. I can help you out no problem.

  4. Tej says:

    My prescription is as follows, I want to know can I use Base 8 curve lenses in rimless or semi rim frame. I spend more time in front of computers and outdoors.

    Right Eye Left Eye
    SPH -3.25 -2.75
    CYL -1.0 -1.0
    AXIS 30 145

    Please help. Thank you for your time.

    Regards,
    Tej

    • msatghare says:

      Tej,

      Thank you for the Inquiry. With That high of a Rx it might be hard to do a Base 8 rimless wrap. You might be better going with a rimmed frame with a insert in it. Please call our customer sertive 888-440-9797 they can go over some options for you.

  5. JOSE says:

    My son just received his Oakley Crosslink XS. I don’t think these are exactly a wrap around type but they are curvier than his original pair. The Oakleys have the same prescription as his original pair of flatter glasses. (R +6.00,+1.00,090 L +6.00,+1.00,080). He complains that the Oakleys don’t work right. (He’s 6) I wondering if the curvature of these lenses is making some of the lens useless, particularly on the outside edges? Do you think these are a bad choice for him or how long before he may get used to them? Thank you.

  6. Raji nair says:

    Dear sir,
    Can i have a curvature frame …
    SPH CYL AXIS ADD
    R -1.50 -1.25 30 1.25
    L 0.00 0.00 1.25

    R -1.46 -1.20 31 1.27
    L 0.04 -0.01 89 1.24

    I have written the way its written on my prescription.

    I work more in computer as i am working in graphics …pls email me if i can have curvature lens

  7. Lai says:

    Hi, I have a patient with Left / right 4PD.
    He feel more comfortable after tested with 2BD on Left Eye.
    This is his first time use prism and he chosen a oakley curved frame. It is possible to put prism on curved frame?

    This patient was wearing oakley curved frame for many years.

    Thanks for your time.

  8. raymond says:

    can I get progressive lenses fitted to my existing frame?
    My frame has high curvature, (sport style).
    My prescription is plano for distance and +1.5 for reading.
    How much is the cost for varilux or zeiss lenses?

  9. KS says:

    sp= -6.5
    cyl= -1.5
    Axis= 135 deg

    Was wondering if wrap around sunglasses would work for me?

  10. carlon says:

    I don’t like how sunlight gets in over the top of my current frames, so I need a hat too. I thought wraparounds would solve this by eliminating the gap over the glasses by my eyebrows, but my prescription is -3.25 sphere and -1.50 cylinder – above the limits of -4 combined that you suggest. What other frames might I try to keep overhead sun from getting over the frame tops?

  11. Drew says:

    Hi,
    Current prescription
    Right -0.75 -0.75
    Left -1.00 -0.75
    For astigmatism

    Was wondering if wrap around sunglasses would work for me?

    Thank you

    • msatghare says:

      Hi, It depends on the frame but if your prescription has a cylinder it must have an axis and your prescription does not have that.

  12. Holly Martel says:

    This info has helped me a great deal, Thank you


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