PAL designs that Compensate for BC's

[Angel of Grace]

I often encounter pt's that are high myopes that want the wrap sunglass frames. Currently I use Shamir's Piccolo with Attitude to compensate for the curve issues. Does KBco have a lens that does the same thing? Would that be the Fushion lens?? Can anyone give me info on any PAL designs that are polarized and work well with wrap frames? Thanks and as always optically yours, Angel of Grace

[optical24/7]

KB Co's is called EOS Wrap. Poly 83mm blank, grey and brown polorized. Power range -4.50 to +2.50.

[HarryChiling]

I don't understand how the Kbco lens is comped for wrap, if the lens is aspheric and lets say you need an 8 base in the poly the range is -4.50 to +2.50, that's a 7.00 D differnce if you were to split the difference you would wind up at -1.00 D, so if we used Darryl's Optical Analysis program (again Darryl the thing is wonderfull, can't thank you enough). A lens that has +0.02 D Mean Power Error at 30 degrees of ocular rotation would have +0.35 D MPE in a power of -4.50 and a -0.04D MPE in a +2.50 power. I am curious how a 8 base with a set asperic value can cover such a broad range better than a spherical lens? If the lens had various asphericity which would depend on the Sph Equiv power ordered than I could see how the lens would be comped, but their product is not more comped for wrap than a image polar.

[Barry Santini]

I don't understand how the Kbco lens is comped for wrap..... I am curious how a 8 base with a set asperic value can cover such a broad range better than a spherical lens? If the lens had various asphericity which would depend on the Sph Equiv power ordered than I could see how the lens would be comped, but their product is not more comped for wrap than a image polar.

Harry, that's because KBco's wrap solutions are a series of many different asphericities designed for the rX range covered, all on an 8BC. If you call KBco, they'll send you their "white paper" and research on the whole thing, incluidng edging, which is *very good* info about wraps.

The bottom line for me on wraps is:
1. It doesn't always have to be an8BC
2. The Rx you start with really determines most success and client satisfaction
3. Many clients love their wraps
4. Some clients, won't, no matter what you do (like progressives)

If the orig Rx IS NOT fully focussed for infinity, then *comp'ing* it will only make things worse to compensate it (comp's result is even weaker in most minus Rxs). This is the main reason why so many labs (MJ, Oakley, Pech, etc). have determined that they won't routinely wrap-compensate moderate minus Rxs. Its avcompounding effect!

FWIW

Barry

[HarryChiling]

Harry, that's because KBco's wrap solutions are a series of many different asphericities designed for the rX range covered, all on an 8BC. If you call KBco, they'll send you their "white paper" and research on the whole thing, incluidng edging, which is *very good* info about wraps.

The bottom line for me on wraps is:
1. It doesn't always have to be an8BC
2. The Rx you start with really determines most success and client satisfaction
3. Many clients love their wraps
4. Some clients, won't, no matter what you do (like progressives)

If the orig Rx IS NOT fully focussed for infinity, then *comp'ing* it will only make things worse to compensate it (comp's result is even weaker in most minus Rxs). This is the main reason why so many labs (MJ, Oakley, Pech, etc). have determined that they won't routinely wrap-compensate moderate minus Rxs. Its avcompounding effect!

FWIW

Barry

Good to know, I wasn't aware that it came in various aspheric values, do you get to order whatever asphericity you want?

I agree it doesn't always have to be an 8. If you were putting back bevels on them like some online dealer I saw here a while ago you could get away with anything that had a back base of 8. Or you could use any base you want and put an 8 base bevel on it (doesn't look great on polaized though). It does depend alot on the Rx as you mentioned, anyway I don't see a magic bullet as far as the process for wraps. Everthing has to be taken into consideration in the moderate to higher Rx's.

One of my tricks is that I clock the frame front with my lens clock and from there I try to match this reading as close as possible. Works very nicely I also like to put front bevels on them to keep them looking clean on the front, but find that on the higher (-) Rx's you have to do a bunch of hand work to make it fit right or use a special bevel which our equipment doesn't have (if I can't do it in office I won't offer it).

Thanks Barry insightfull as always.

[AWTECH]

I often encounter pt's that are high myopes that want the wrap sunglass frames. Currently I use Shamir's Piccolo with Attitude to compensate for the curve issues. Does KBco have a lens that does the same thing? Would that be the Fushion lens?? Can anyone give me info on any PAL designs that are polarized and work well with wrap frames? Thanks and as always optically yours, Angel of Grace

ICE-TECH Advanced Lens Technologies offers a proper compensated individualized solution using digital surfacing. If the frame is designed for an 8 base the front curve is an 8 base and the back surface is designed for the panto and the wrap angle. If the frame has a plano 6 base then the optical backside is designed around the 6 base front geometry.

If you want more information please call or e-mail ICE-TECH
Phone: 888-423-8324
E-mail: info@ice-tech.com

[Angel of Grace]

Thanks for all the information on this subject. I agree that the BC of the frames lenses should always be considered as an important aspect of how the glasses will turn out. Some RX's just won't go on steeper base curves. It kinda goes back to BC theory. A total power of the lens, the lens design and technology used to create the lens as well as the shape of the frame and where cylinder axis lies at all help to create the best possibilities for the patients. I enjoy helping people get not only good visioin but fabricating a great looking pair of suns that fit and function superior.

I work for large practice and we have our own lab. I will look into some of your suggestions. Thanks.

[HarryChiling]

I work for large practice and we have our own lab. I will look into some of your suggestions. Thanks.

Why didn't you say you had acess to a lab. Is it surafceing? If it is I can give you some really good information on lenticulars used as a carrier curve for higher Rx lenses. I am thinking of making software for computing this if I ever get free time in my life again.

[Angel of Grace]

Harry, wouldn't the bowl effect of the lenticular carrier tend to make the lenses look weird?? I understand that they would be aspheric but i am getting a mental picture of how it would look in such curved frames. If i was to use a flatter BC sunframe like 6b it probably would look better. This is a way to address the higher power RX's and could probably be accomplished in house surfacing. The lens from Ice-Tech Advanced Lens Technologies is one I'd like to learn more about but would have to be done out of house due to digital surfacing so it probably cost just as much or more than Piccolo with Attitude. Can anyone give me comparisons or feedback of Piccolo with Attitude versus EOS wrap solutions. Can anyone tell me if EOS wrap solutions is available to the smaller labs for surfacing??

[AWTECH]

Harry, wouldn't the bowl effect of the lenticular carrier tend to make the lenses look weird?? I understand that they would be aspheric but i am getting a mental picture of how it would look in such curved frames. If i was to use a flatter BC sunframe like 6b it probably would look better. This is a way to address the higher power RX's and could probably be accomplished in house surfacing. The lens from Ice-Tech Advanced Lens Technologies is one I'd like to learn more about but would have to be done out of house due to digital surfacing so it probably cost just as much or more than Piccolo with Attitude. Can anyone give me comparisons or feedback of Piccolo with Attitude versus EOS wrap solutions. Can anyone tell me if EOS wrap solutions is available to the smaller labs for surfacing??

Private message me with your e-mail address and I will get you the price information so that you can compare the ICE-TECH digital individualized solution. You will be see that it is not that expensive when you consider the backside AR and super hydrophobic, edging challenges for wraps etc.

[cjbails]

Can anyone tell me if EOS wrap solutions is available to the smaller labs for surfacing??

Angel - Wrap Solutions lenses are available to any surfacing lab that wishes to order. They are no different, in terms of surfacing, than any other polarized lens with the exception that they are 83mm in diameter and 13mm thick. Even so KBco makes available a laboratory processing manual if there are any questions. I would be happy to send you information if you like.