# Optical Forums > Ophthalmic Optics >  Wavefront Guided Spectacle Lenses

## musicvirtuoso

Quick poll, guys:

I'd like to know anyone's take on Wavefront Guided Spectacle Lenses, like those from Ophthonix (iZon). I'd also like to get your input on the lenses by Zeiss (i.Scription) and WaveForm. What has been you experience with these lenses? Are patients generally satisfied with the results? How is each lens marketed to the patient? I am looking for experience in the efficacy of lenses which take high-order aberrations into account. I understand that iZon is different than the other ones in that it actually has correction for the aberrations (the lens is more complex than I care to go into, I just want to let posters know that I know how the lens is made). Do you think that there is any point to having the layer for correcting those aberrations? (I understand that both Zeiss and WaveForm have clearly stated that they believe it is not effective to try to treat the high-order aberrations as iZon has). Anything that you want to discuss with this is great! Thanks everyone!

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## Darryl Meister

> I understand that iZon is different than the other ones in that it actually has correction for the aberrations (the lens is more complex than I care to go into, I just want to let posters know that I know how the lens is made). Do you think that there is any point to having the layer for correcting those aberrations?


Unless their product has dramatically changed recently, iZon lenses do not correct high-order aberrations any more than similar products on the market. Nor does the glue layer serve as an optical correcting layer for high-order aberrations.

Although I believe that Ophthonix initially experimented with a "programmable" glue layer, I believe that this approach was eventually abandoned.

As already described in several threads on Optiboard, you cannot eliminate the high-order aberrations of the eye with a spectacle lens without introducing even more significant aberrations away from the center of the lens.

It is unfortunate that sometimes the laws of physics get in the way of marketing.

Best regards,
Darryl

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## musicvirtuoso

> Unless their product has dramatically changed recently, iZon lenses do not correct high-order aberrations any more than similar products on the market. Nor does the glue layer serve as an optical correcting layer for high-order aberrations.
> 
> Although I believe that Ophthonix initially experimented with a "programmable" glue layer, I believe that this approach was eventually abandoned.
> 
> As already described in several threads on Optiboard, you cannot eliminate the high-order aberrations of the eye with a spectacle lens without introducing even more significant aberrations away from the center of the lens.
> 
> It is unfortunate that sometimes the laws of physics get in the way of marketing.
> 
> Best regards,
> Darryl


Thanks Darryl for responding. I was honestly hoping that you would put in your 2 cents. I actually had to do a bunch of my own research into this lens. When I asked Ophthonix for a white paper or more technical details, they were only able to send me their marketing stuff. It's kind of like trying to get information about the president or something. HAHA. Based on the patent and some presentations that I found about the lens, they _are_ doing that "programmable layer". You very well may know more than I do about if this actually happened.

I understand their explanation of how they manage doing this in a spectacle lens although I'm skeptical, as most are, about the efficacy of that method. I also understand the issues that can arise if that is done in a spectacle lens. Unfortunately, our rep doesn't really know anything about optics, so he was only able to tell me what he was told by their marketing department. 

I doubt that there is anyone else here that would be privy to technical information that you are not, so I'll keep trying to dig for info from Ophthonix. That being said, I'd still like to see if anyone has any patient feedback on _any_ of these lenses. I just want to get some input on that. 

Thanks again, Darryl. I always appreciate and absorb anything you have to say.

Drew

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## sharpstick777

In a literal sense, the word Waveform is simply synonymous with aspheric.  

As far as marketing hype, it will depend on the company who is using it.  In regard to lasik surgery, the theory is that it can correct irregular astigmatism based on varying the amount of correction on each axis, asymetrically.  In regard to opthalmic lenses, we don't have the same ability simply because the eye moves in relation to the lens.  We don't always look through the center like we do our corneas.  Correcting that in opthalmic lenses can simply cause more problems than it solves, as Darryl said.

There is the Wave-front technology of Essilor, which is essentially a distance aspheric design in simplest terms.   In my guestimate of what they are trying to do (its incredibly vague) is that its an aspheric design optimized on the larger pupil size during night vision.  But there is no proof of that per se, I am just trying to be generous.

In general, if the company can't explain it, it doesn't really exist.  

I do want to credit both Zeiss and Seiko, who have made their engineers easily available to answer the though technical question I have had about their products.  I prefer transparent companies.  




> Quick poll, guys:
> I'd also like to get your input on the lenses by Zeiss (i.Scription) and WaveForm. What has been you experience with these lenses? Are patients generally satisfied with the results? How is each lens marketed to the patient? I am looking for experience in the efficacy of lenses which take high-order aberrations into account.

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## Darryl Meister

> When I asked Ophthonix for a white paper or more technical details, they were only able to send me their marketing stuff


Well, you can certainly get a white paper on i.Scription!




> Based on the patent and some presentations that I found about the lens, they _are_ doing that "programmable layer".


Yes, they have a patent on a "programmable" glue layer. And, yes, they may have the capability of applying a small correction for high-order aberrations, at least within the narrow physical limits of altering the optics of the glue layer. And, at one time, they may have even supplied such lenses. However, I am under the impression that this is no longer the case.

None of their current marketing materials that I've seen explicitly state that these lenses correct the high-order aberrations of the eye. Nor do they provide any optical examples of their lenses with corrections of high-order aberrations. And at least one published evaluation of iZon lenses (by Professor Rolf Blendowske) did not reveal any correction of high-order aberrations. Further, they have an entire line of lenses with _no_ glue layer (i.e., the "SL" line) that is marketed with the same visual benefits.

But, more importantly, and as I routinely point out, there is no way to correct the high-order aberrations of the eye with a spectacle lens, without making vision significantly worse everywhere else. So, even if their lenses did provide this type of correction through a given point of the lens, vision would actually become significantly worse than providing no high-order correction at all within a few millimeters of this point. I imagine that this would be reason enough to abandon the idea.

That said, I obviously do not work for Ophthonix, so I can only respond based upon my own assessment of available information. So, if you suspect that their iZon lenses still do offer such a visual benefit, I would encourage you to contact Ophthonix directly to request some actual technical details, examples of actual lens measurements with a wavefront sensor, or any other available evidence of to support such a product claim.




> There is the Wave-front technology of Essilor, which is essentially a distance aspheric design in simplest terms.   In my guestimate of what they are trying to do (its incredibly vague) is that its an aspheric design optimized on the larger pupil size


It is important to note that Essilor's selling proposition is a reduction in the high-order aberrations of the _progressive spectacle lens_, not the eye. Like low-order astigmatism, high-order aberrations in a progressive lens are an unavoidable consequence of the change in progressive power. So Essilor is claiming to better manage these aberrations.

You could "manage" the high-order aberrations of a progressive lens design, for instance, by using a merit function with one or more terms associated with rates of change in power; increasing or decreasing the regions of "sphericalness"; or applying other clever design techniques, depending upon the intent of the lens designer. Essilor apparently also changes the pupil weighting now as a function of height, which could also be factored in.

Maybe Pete Hanlin can provide some additional details regarding Essilor's technology.

Best regards,
Darryl

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## musicvirtuoso

> In a literal sense, the word Waveform is simply synonymous with aspheric.  
> 
> As far as marketing hype, it will depend on the company who is using it...


When I used the term "WaveForm", I was referring to the company named _WaveForm_, which produces lenses based on "optimized wavefront refraction", much like the i.Scription (as far as I understand it).  All three lenses (i.e. iZon, i.Scription, and WaveForm) are produced based on a "wavefront enhanced" Rx - that is, an aberrometer is used to determine a "more accurate" refraction which takes high-order terms into account. While the prescribing doctor is generally given license to alter the given Rx, I believe it's generally recommended that the lenses be made directly from that computer generated Rx (trying not to open the "subjective vs. objective refraction" can of worms). I'm just seeing if people have generally seen patient reactions consistent with the marketing of these lenses. For instance, iZon has had studies that show improved night reaction time, which may be perfectly valid. However, they also throw around the terms HD, and "wow vision", which generally doesn't coincide with patient's experience (at least not what people think those terms should mean).

I'm not looking so much to compare these lenses to each other, but rather to compare them to "standard" lenses (for lack of a better term). Thanks again for everyone's input.

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## musicvirtuoso

Oh Darryl, if only all companies were as accessible as you, we probably wouldn't have some of the problems we do. I agree that I should do more digging. It's not so much that I'm convinced 100% that the lenses do what I mentioned. I'm just trying to get a straight answer from them. I have noticed the vagueness of their materials and hope to find answers soon. 

I'm not using this as a gauge of which lens to pick, we already have the iZon lens in our office. It is really just for informational purposes. I'm just curious how people are selling these types of lenses and how patients react to them.

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## Darryl Meister

> Oh Darryl, if only all companies were as accessible as you, we probably wouldn't have some of the problems we do


Of course, you could also avoid this problem by just doing business with accessible companies.  :Wink: 

Best regards,
Darryl

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## musicvirtuoso

> Of course, you could also avoid this problem by just doing business with accessible companies. 
> 
> Best regards,
> Darryl


For as much as I would love to try out the i.Profiler, etc. I can't persuade the OD (who owns the business) to invest in it. Maybe eventually.....? I did stumble upon a long and heated thread about iZon when it first came out. Very interesting views. I contacted Ophthonix for more info, but doubt I'll be hearing back from them any time soon. Darryl, do you or anyone you know have the i.Scription or that lens from WaveForm? I wanted to know if this system (i.e. aberrometry taken into account with glasses, independent of manufacturing process) is effective. I know there is a lot of hype now behind high-order aberrations what with these lenses, PSF-based refractions, etc. Interested in some input on that as well. Thanks!

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## Judy Canty

Have you talked to your Zeiss rep about it?  Howie can probably help you with the doc and the financing.

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## Dave Metzger

iZon is AMF = Adios My Friend

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## wizardofeyes

Since iZon has gone out of business the HRK-8000A has been a wonderful replacement Aberrometer.  It is better in that it actually gives your K values too!.  This instrument has an open platform as it allows you to order HD lenses from ANY manufacture.  Whit iZon they would blend the HOAs into the LOA Rx at their lab.  With the HRK-8000A by Huvitz the info is sent to a cloud server, then optimizes and blends the HOAs into the LOA Rx and sent back to the instrument all while the patient is still sitting in the exam chair.  

Right now until the end of 2012 Veatch Ophthalmic Instruments is taking the Z-View in on trade and has an extremely aggressive pricing structure.  If you are interested in learning more about this then shoot me an email. tag@voi2020.com

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