The truth about Camber

[ThatOneGuy]

Does anyone remember when progressive lenses used to be sold on the merits of their design? "This lens will give you wider intermediate," "That lens provides you with the most add power," "The other lens wont work with a seg over 17," etc.

Does anyone remember when a new lens hit the market, it would be availble in one or two lens materials only? Other materials and photochromics and polarized versions would come out "eventually."

The promise of freeform lenses was that we would have better correction for unwanted astigmatism and all materials available on all lens designs immediately. Period. That was the promise.

The more complex the design gets on the front surface OF A FRONT SIDE MOLDED PRODUCT, the more limitations you have in product availability and advancement. Also, the SIGNIFICANTLY higher overhead costs to labs who must stock the various complex options available.

Can someone explain to me why camber lenses are being presented as a huge step FORWARD? I fail to see based on any information presented that camber is any improvement over, say, a Hoya lens, or the physio 360. No one lens design works best for everyone, and yet the camber lens seems to present a one size fits all lens via its elephant trunk molded lens. At least the Individual 2 adjusts corridor lengths based on many perameters, and Autograph offers multiple fixed corridor lengths.

So said another way, I guess I'm asking if anyone can explain how camber isn't just a front molded progressive with backside optimization.

[Tallboy]

Because it is a plano blank not one with a molded add. It is different because of this. Any number of progressive designs could be cut on the backside in theory. The blank would have a different base curve for the DV rx and the NV RX, all on the same plano blank. In theory optimizing this - especially for hyperopes. I've had meh results though others (such as Craig on here) have said they have great results. I think it comes down to what designs are being used - I probably used the wrong labs who chose poor designs (cheaper?)

I haven't been won over by it for the same reasons of higher overhead / lack of extra "wow" results. However labs would only have to stock "camber blanks" in base curves not base curves AND adds. But yeah.

[ml43]

All other front side molded PAL's besides the Camber have areas of converging and diverging curves(front to rear relative).

The Camber is converging across the entire surface, and is horizontally spherical.

It's not a front side molded PAL, it's just a special aspheric lens, that was designed to help optimize free form PAL optics.

[Craig]

It is our lens of choice. We only offer the Camber and use another if we have no choice but the compensation and zones are our favorite.
Best Lens Made and only one the is actually an improved design of the blank!

[hyperoptic]

Camber is a step forward because it helps address many of the concerns found in single vision frontside Digital PAL's, it allows for flatter curves in plus powers, better thickness profiles, and wider fields of view. By combining the two surfaces (the front is a continuously variable surface not a PAL) together patients experienced easier adaptation, better near visual performance, and overall better comfort (these were the results of our wearer trial) Advantages for the ECPs are availability and flexibility, the designs can be decentered, its available in materials from CR-1.67 polarized, Trans, and clear. The principals behind it are not new, they are based in science that is well accepted in practice, we just applied the Tscherning ellipse to a digital platform. Camber lens technology can be used with 4 different lens designs each developed for lifestyle selection in mind, with corridors in one MM steps with a minimum fitting height of 14. If you'd like more information give me a call and I will send you some more information and answer all your questions. Kurt Gardner 336.529.9284 (Im with IOT)

[Robert Martellaro]

Can someone explain to me why camber lenses are being presented as a huge step FORWARD?

Flatter moderate plus lenses with a full backside PAL surface for hyperopic absolute presbyopes without a positive ocular curve or the use of high refractive index low Abbe lens materials.

No royalty fees to Zeiss.

Camber is a step forward because it helps address many of the concerns found in single vision frontside Digital PAL's, it allows for flatter curves in plus powers, better thickness profiles, and wider fields of view. By combining the two surfaces (the front is a continuously variable surface not a PAL) together patients experienced easier adaptation, better near visual performance, and overall better comfort (these were the results of our wearer trial) Advantages for the ECPs are availability and flexibility, the designs can be decentered, its available in materials from CR-1.67 polarized, Trans, and clear. The principals behind it are not new, they are based in science that is well accepted in practice, we just applied the Tscherning ellipse to a digital platform. Camber lens technology can be used with 4 different lens designs each developed for lifestyle selection in mind, with corridors in one MM steps with a minimum fitting height of 14. If you'd like more information give me a call and I will send you some more information and answer all your questions. Kurt Gardner 336.529.9284 (Im with IOT)

Hello Kurt. I have a few questions.

Is Camber optimized for position of wear with full Rx optimization over the entire lens?

If true, is there design optimization (zone configuration, periphery design, corridor length, etc.)

Is there an Rx tweak at the distance and near reference points? If so, I would expect to see a compensated Rx.

What are the maximum plus powers (max distance plus near) for Trivix and 1.60?

Best regards,

[hyperoptic]

Is Camber optimized for position of wear with full Rx optimization over the entire lens?

If true, is there design optimization (zone configuration, periphery design, corridor length, etc.)

Is there an Rx tweak at the distance and near reference points? If so, I would expect to see a compensated Rx.

What are the maximum plus powers (max distance plus near) for Trivix and 1.60?

Best regards,

Camber is a compensated lens using Digital Ray Path Technology (www.digitalray-path.com) we are maximizing the fields of view along the entire surface of the lens using default or provided POW measurements, we take the personalization further by allowing the selection of a design that can be matched to a persons lifestyle, (Larger distance, balanced, larger reading zone, and a softer design for first time PAL wearers) This will mean that you will get a compensated Distance Rx and add power.

Maximum powers can vary slightly and we are always trying to make a lens more efficient, I would contact your Camber lens provider (if you dont have one visit camberlens.com for a list) and they can let you know their power restrictions.

Thanks

[Robert Martellaro]

Camber is a compensated lens using Digital Ray Path Technology (www.digitalray-path.com) we are maximizing the fields of view along the entire surface of the lens using default or provided POW measurements, we take the personalization further by allowing the selection of a design that can be matched to a persons lifestyle, (Larger distance, balanced, larger reading zone, and a softer design for first time PAL wearers) This will mean that you will get a compensated Distance Rx and add power.

Thank you.

I see that the inset is calculated for work distance as well as IPD, vertex distance, and Rx. I would expect to see that from a FBS PAL; there's no reason not to implement that calculation unless it's a low end design. After all, some of the premium semi-finished lenses have some degree of inset and corridor length optimization for base curve and add power.

A couple more questions if I may.

If we map a plano sphere +2.50 add PAL, and a +1.50 -3.00 x 45 PAL, many PAL design cylinder plots take on a significantly deformed appearance. Does the Digital Ray-Path® technology modify the PAL optics so that the intended PAL design is reasonably true across a very wide range of RXs and fitting parameters? If so, is it calculated in real-time?

WRT the distance, balanced, and near designs, could you describe the tradeoffs made when going from one design to another, specifically the distance and near zone widths and their associated corridor lengths.

Maximum powers can vary slightly and we are always trying to make a lens more efficient, I would contact your Camber lens provider (if you dont have one visit camberlens.com for a list) and they can let you know their power restrictions.

I'll do that (Walman is my primary lab). I understand that it's hard to pin this down unless we know a little about the frame shape, size,and decentration, primarily with plus powers.

Best regards,

[Sphinxsmith]

We've been using Camber lenses from Identity in IL and have been very happy with them. In fact they are appreciably less expensive than the conventional lens we had been using.
They've been extremely versatile and I'm not having to hop around from lens to lens and lab to lab to get just the right product.

cs

[Jason H]

Dunno, I've had as many hits as misses with camber. It makes so much more sense from a surfacing standpoint for hyperopes instead of myopes. Interesting stuff, but better? Physics has laws instead of guidelines for a reason.

[Robert Martellaro]

My Rx -9.50 +1.00 x 115 +2.75 add
-9.25 + 1.25 x155
Previous wore Ind 2 and another IOT design and GT2 3D

Thanks rdcoach5. We've both been around long enough to know that there's no single design that's optimal for all RXs and individuals.

Dunno, I've had as many hits as misses with camber. It makes so much more sense from a surfacing standpoint for hyperopes instead of myopes.

Yup. Working the steepest curve makes the most sense, and that's why a spherical front with the progressive optics on the back works better with minus, but hard to do with plus (expensive to work both surfaces). Camber looks like a nice in-between work around, that is, only a moderate increase in cost, due to the proprietary blanks, without significant optical compromises compared to surfacing the progressive optics on the front of the lens.

[Sphinxsmith]

This was a nice breakdown on the tech.
http://www.2020mag.com/ce/TTViewTest...essonId=111613

cs

[Robert Martellaro]

This was a nice breakdown on the tech.
http://www.2020mag.com/ce/TTViewTest...essonId=111613

cs

Anyone else having a problem with the statement that non-camber FBS PAL designers use up their design tools to correct optical problems created by a single vision front surface?

[Craig]

Anyone else having a problem with the statement that non-camber FBS PAL designers use up their design tools to correct optical problems created by a single vision front surface?

He is speaking of prioritizing the design and it makes sense to me. I learned that the diopter drop is 2 from the distance and actually 1 above the MSRP; did not know that.

We use this lens 100% if we can and all wear it as well.

[ThatOneGuy]

Anyone else having a problem with the statement that non-camber FBS PAL designers use up their design tools to correct optical problems created by a single vision front surface?

Yes. It is grossly apparent that the person writing the article has never been involved in 3D modeling or calculations. There is no such thing as "using up" design tools.

I'll write more later.

[ml43]

Yes. It is grossly apparent that the person writing the article has never been involved in 3D modeling or calculations. There is no such thing as "using up" design tools.

I'll write more later.

depends on what you define as a "design tool"

if we are talking about zernike coefficients to optimize a conic, after about the 10th term, things get a little messy, especially from a manufacturing/metrology stand point.

[Uncle Fester]

This was a nice breakdown on the tech.
http://www.2020mag.com/ce/TTViewTest...essonId=111613

cs

DISCUSSION: WEARER TEST

IOT, in association with the University of Madrid, designed and conducted a double-blind wearer trial comparing a Camber finished lens with one processed from a single vision blank. Both used the same contemporary IOT back-surface progressive design technology. Both prescriptions were made from the same material, same central base curve, in the same frame, and worn for one week each. The only difference between the two pairs of eyewear was the lens blanks they were processed from: Camber versus single vision. Wearers and testers were unaware of which lens was which. After trying them both, wearers were then asked to compare lenses.
When asked, "Which lens do you prefer the most?" wearers preferred Camber 2 to 1. Regarding ease of adaptation, 8 of 10 reported that adaptation to Camber seemed easier. Nine of 10 reported better near vision. Considering all factors, 55 percent (a majority) found Camber better, 39 percent found it to be equal.
Wearer trials like this are not very common today because it is very tough to show significant differences in wearing experiences. Test subjects find it difficult to differentiate and express their preferences. Additionally, the trials are very expensive and time-consuming to perform. Therefore, these reported results are significant.

I'd like to see the powers of the 6% who did not feel the lens was better or as good.

Did they randomly vary or were they specific to higher plus/minus or cylinder powers?

[Robert Martellaro]

I'd like to see the powers of the 6% who did not feel the lens was better or as good.

People are strange.

[ThatOneGuy]

I'd like to see the powers of the 6% who did not feel the lens was better or as good.

Did they randomly vary or were they specific to higher plus/minus or cylinder powers?

My interpretation of the wearer test was that they were comparing IOT vs IOT. The limitations are in their math, and I would be curious to see how those same 6% feel about Hoya vs Seiko vs Shamir vs Zeiss designs.

Additionally, I wonder how long the patients wore each product.

[Jason H]

Again, minus curves ought to be on the concave surface.

[Jason H]

And a -5.00 with a +2.00 add is still minus all the way around

[optical24/7]

I glanced over the above 20/20 article. What I didn't see was how the Camber lens addresses the vertical cyl induced outside the umbilic by increasing the BC from top to bottom. Maybe Kurt could tell us here.

[Robert Martellaro]

It's vertically oriented, something that Essilor showed to be less upsetting to the wearer than an oblique orientation.

I hope they don't have to use up all of their design tools compensating for the more complex aspheric surface though.

[optical24/7]

I hope they don't have to use up all of their design tools compensating for the more complex aspheric surface though.

Now that's funny!


I'll be putting the Camber through my own blind vetting process with my persnickety engineer patient base with next year's "Exploratory Budget".

[ThatOneGuy]

It's vertically oriented, something that Essilor showed to be less upsetting to the wearer than an oblique orientation.

I always saw their claims about that as disinformation to try and combat Zeiss' horizontal symmetry patent from the 80s.