It was nice to see this board is an integral part of our industry, I am sure Steve is proud of that. I am also pleasently suprised by Zeiss, Essilor, and Schneider. They stepped up and offered information that I am sure will lead to better sales and better informed opticians.Originally Posted by TLG
ok foot in mouth...i fitted my dad with physio 360's and he loves them!!...looks like i deserve all the shots now!!
equal opportunity offender!!
Darryl, it sounds like the polishers are the weak link in the free-form process and need a form of truing occasionally.
Bob Taylor
The polisher is really just one potentially weak link in the chain. Both the generator and the polisher have a significant number of parameters that must be individually set for each job. These parameters are sent along to each machine in a separate file (in "G-code" or with other machining commands). The type of tools and other processing related parameters, such as equipment calibration and slurry quality, are also important variables. The center defect that AWTECH mentioned earlier, for instance, will result when the diamond cutting tool is out of alignment, producing either a "dimple" or a "nipple" defect once the lens starts spinning. In any event, since you can no longer rely on one or two power measurement points to determine whether you've surfaced a "quality" lens, a good free-form surfacing process should be complemented with a measurement system capable of "mapping" the entire lens.
Darryl J. Meister, ABOM
Just make sure this information isn't shared with anyone, a simple it's right will suffice. :D (sorry but if your pitching I'm batting)
The point Darryl makes is correct that a mapping of the lens will confirm that a freeform lens is made as it was designed, however these same method should also be used to conform front molded PALs since errors in blocking etc. would cause error in the lens design.
I know that different freeform surfacing systems remove different amounts of lens material. We developed our process to produce the surface in a manner that does not require for any significant removal of lens material after this production. Most lenses receive a hard coating of approximately 4 microns. This does not have a bearing on the lens power for spectical lens use.
Harry,
Are you suggesting that a printout of the lens mapping results be included with the finished order? That not only seems a reasonable request, but since none of us have the equipment to verify ourselves, should be mandatory I think. How else are we to know if it is correct? I totally agree - I'm not at all comfortable with my lab simply telling me it's right (I have plenty of problems with them on orders I can verify).
-Tony
This is analogous to performing a quality audit or inspection as part of an ongoing quality control program. Manufacturers, regardless of industry, generally do not supply this kind of information or data, just as you do not supply your own patients with this kind of information. Besides, what you were asking about previously was an optical analysis of the lens design, not really an analysis of surface quality, which is an altogether different discussion topic. The most accurate surface analysis devices, such as precision coordinate measurement machines (CMMs), generally cannot even perform an optical analysis directly.Just make sure this information isn't shared with anyone, a simple it's right will suffice.
Darryl J. Meister, ABOM
As Darryl pointed out, this is a complex issue and you are asking for a lens map with each order.
Do you want a sphere map? Do you want a cylinder map? Do you want verification of powers across the lens at various points? (say 5mm x 5mm). If you had these powers across the lens what would do with the information other than trust the manufacturer that the power they state is located at that point is correct?
The industry has been trained with point verification and now many are trying to make surface comparisions as simple as point comparisions. It is not that simple.
You know Allen, I get personally tired of your defensive posture on this subject. I'm willing to admit that I don't know how it is you verify them so I can't possibly tell you what I would like to see. Are you willing to admit that you have never been in our shoes and so you may never understand how important it is to us to be able to verify?
You continue to claim that the integrity of the lens is verified at the lab - give us what you know. Let us decide what is too much or too technical information. All of us have had to learn new skills to do the work we do each day. Are you suggesting we can't learn what you have? What makes you so much smarter than us? Sure, if you sent me some kind of mapping information today I would be clueless looking at it. But if all of us got one everytime we ordered this type lens, you can be darn sure we would take classes or read up on it so we could understand. I think it's arrogant to tell us we don't deserve it because we don't know enuf to understand it. If there does exist some type of readout and your only reason for not providing it to us is that you don't think we would understand it, I think that is very shallow thinking and frankly, somewhat insulting. What if you had no way of verifying lenses but your equipment manufacturer told you, "Just send them out, they'll be perfect." Would you be comfortable with that? I doubt it. If your answer to that question is 'NO' you should be able to empathize a little for what we're talking about. And if your answer is YES, you're a liar.
I do have respect for the knowledge you possess and appreciate what you have to offer this board. I also understand your desire to give proper representation to your spoke in the wheel (the lab). To be honest, I may actually trust YOU to do my work. The problem is that you can't speak for every lab on earth so the question each of us has to ask is if we can trust OUR lab. Sometimes I think you take our questions and comments way too personal.
I did not write this as a personal attack on you Allen. It's just that throughout this thread you continue to tell us we don't need to know what we would like to know. I really don't think you can understand our position if you haven't walked in our shoes.
Respectfully,
-Tony
I don't take this as a personal attack. It is not that the desire to know is wrong. As you admit, you don't even know what you are asking for. I think in concept what you are asking for is logical, but the need is not as you believe. At some point you have to have confidence in your lens manufacturer. This can be a combination of blank provider, lens design provider and lab facility that produces the lens.
The chance of a lens design that we produce being not correct and not detectable by your current methods is way less than 1%.
To accomplish what I think, you think you need would require an investment by the retailers of between $50,000 and $150,000 plus training on the use of the equipment. You would also have to have the suppliers agree to provide comparision data files. (I doubt many would be willing to do this since with enough data files there lens designs could possibly be reverse engineered.)
This is like asking Microsoft to provide you with their source code for Office so you can check their software. Once they provide the source code, you don't need them anymore. Not that a one store optical is going to do this, nor is an individual user of source code going to write their own programs, but a competitor of the lens manufacturer or a competitor of Microsoft would both have an interest in having a very low cost investment compared to the developer.
We are in the process of providing these lens maps for each job with each order. This should be ready right after the first of the year. You can get an idea of the usable area of the lens from these, but you can not compare this to the lens you are replacing unless it was made by the same manufacturer.
Unfortunately, what you and others think is so easy to provide, is quite complex and made to see very simple when you read about this type of technology or see the equipment at an optical trade show.
Do we make mistakes, yes. Do we correct them, yes. Other than mistakes that are correctable due to human error, such as wrong info entered in the data entry program, we have less than 1% non-adapts. The lenses we produce are verified by traditional means and the patients can see. The patients benefit from the improvements in their vision with our lens technology. You and a few others have asked similar questions and assume that our lenses will not work for your patients because you can not perform a very high level verification. You have to ask other than the fact you think you need this information, why do you need it? What is the cost benefit for having it? Will your patients pay the extra costs of this verification? Look at what is charged for lens edging and mounting. If it takes an investment of 2 to 3 times the finishing equipment what will you have to charge your patients for this?
I am trying to explain this so that you and the others will understand that it is not a zero cost solution.
You can purchase equipment to verify any lens, map each uncut you order, freeform or not. Your Doctor will have to provide you with the data based on the viewing angles of the bundles of rays concept to verify that the lens is producing the powers at the points desired. This way you would be providing knowledge that you are having lenses produced to solve the vision problem based on the Doctors prescribed power needs. (Unfortunately this level of Doctor prescribed Rx across the lens is not available.)
I hope this helps clairfy some of the challenges with a complex lens design and the thought that easy verification at no cost to the retail optical is possible.
We provide very functional lens products, that work. It is surprising that we don't have these type of requests from opticians using our lenses, only from those who are not using them. If you order and dispense 10 pair and then feel like we are not producing a working product for your patients I can see the push for a solution, but this whole concept is a push by those not using the products for a solution that may not be necessary. How necessary is this if the cost per retail optical is $150,000?
I don't assume that in any way at all and I can practically guarantee you that few others on this board would make that assumption. It isn't about that. Many of us have done this for longer than we wanna admit and we are used to a certain protocol when we receive orders from our lab. One of the primary concerns for us is that the lenses were made as we ordered them. If you haven't been 'one of us' I can understand why it seems so simple for you to think that we can somehow just let that go. Maybe we can in time or maybe we will have to eventually, but it goes against the makeup of any seasoned ecp to receive a pair of lenses and simply call the patient and tell them they are ready. We are all used to making that call after we have personally checked the product against what was ordered. That is the point I was trying to make in my post - I just don't think you understand how important it is to some of us because you haven't been in our shoes. That's not a knock on you (and I thank you for not taking it that way).
If my lab had it and provided me with a readout, why would I have to purchase it also?How necessary is this if the cost per retail optical is $150,000?
Take care,
-Tony
Until you provide the mathmatics to those smarter than me I hope you know no paper verification will be acceptable (ie. the X ray pipe welds at Three Mile Island "passed" inspection since they were copies of perfect welds).We are in the process of providing these lens maps for each job with each order.
Again I humbling show my ignorance but when you say your lens is 30% wider than others is that from a corridor width of 2, 4, or 6 mm. It would IMHO make a difference.
TLG said:Look at the above statement: You can confirm that a lens we make using our individual surfacing, just like you confirm a standard front molded PAL. You can use the same equipment. If the far vision sphere is correct, you pass this, if the cylinder power and axis is correct you pass the lens, etc.One of the primary concerns for us is that the lenses were made as we ordered them. If you haven't been 'one of us' I can understand why it seems so simple for you to think that we can somehow just let that go.
You don't confirm the configuration of the molded surface, do you? So why do you have a need to confirm the surface we produce if the standard confirmation methods will verify the lens?
TLG Said:Because you said you need to verify the lens yourself. (Why do you need a standard lensometer if your lab could provide you with the powers in the lens?)If my lab had it and provided me with a readout, why would I have to purchase it also?
Uncle Fester said:This is the approximate additional widith in the corridor for like powers compared to a molded PAL. The corridor width varies depending on the Rx, cylinder and axis. The management of power error and off axis error can be managed much better than a fixed molded design. The patients notice the difference. No distortion in the design by managing these issue with each individual design.Again I humbling show my ignorance but when you say your lens is 30% wider than others is that from a corridor width of 2, 4, or 6 mm. It would IMHO make a difference.
I would like to be able to explain our technology so that more and more optical professionals will better understand this type of technology and how these lenses can benefit their patients.
Please understand that when I first started developing these lenses for individual trials I thought I understood the designs and opportunities for the patients. After three years of producing these lenses I still learn more and more about the benefits. I also am constantly learning more and more about how to explain the many dynamics to this different approach to lens design and production.
Last edited by AWTECH; 12-01-2007 at 12:37 AM. Reason: Added sentance
What's the sum difference between the corridor width of a "molded PAL" and a "fixed molded PAL" in a pl/+1.00 +2.00 +3.00 add?This is the approximate additional widith in the corridor for like powers compared to a molded PAL. The corridor width varies depending on the Rx, cylinder and axis. The management of power error and off axis error can be managed much better than a fixed molded design. The patients notice the difference. No distortion in the design by managing these issue with each individual design
I'm sorry but your qualifying "appoximate width in the corridor" also can't help but raise my eyebrows.
The last sentence has me going huhn
Last edited by Uncle Fester; 12-02-2007 at 12:55 AM. Reason: specify powers
The Minkwitz Therom:
P=Astigmatic Power
M=Mean Power
x=lateral measure from the umbilic
y=vertical distance to acheive the mean power change
This is a good indicator for how wide a progressives corridor is going to be. If I had a map of a lens I could easil confirm if the lens corridor is 30% wider than it shoudl approximately be. And before desings gets thrown around like some sort of neutralizeing word keep in mind that the minkwitz theorom isn't fool proof and is an estimate, but it holds true for the umbilic of the lens fairly accurately. Now I know that the just the movement of the lens surface from the front to the back gives the increase of the corridor width of 8% negatign any effects of power from the equations.
example of 4mm coridor length, 2.2mm thickness, and back vertex to center of ocular rotation of 27mm.
tan(x)=4mm/27mm+2.2mm
tan(x)=4mm/29.2mm
tan(x)=0.1370
x=7.8o
tan(x)=4mm/27mm
tan(x)=0.1481
x=8.4o
That's a difference of 0.6o which is 0.6o/7.8o=0.0769 or roughly 8% increase in width now that's assumeing some figures here but if the lens was fit closer the numbers look better. I would just like to verify for me personally that the lens supplied isn't just a standard desing surfaced on the back (which is still old technology being wraped in a pretty bow). I would like to check off axis powers, but I can't with my lens clock because the surface has the progressive on it so it's for sure going to throw my clock off, my lensmeter could give me the power in various points but it would take me forever to verify more than a few spots on the lens. So then like metioned above I check the DRP, NRP, and PRP and then just assume the rest is right. The idea is for me to put every patient of mine in a lens that costs me double what I am currently payign for lenses, I have no way of verifyign or obtainign data to confirm the lens is truly better, and my current non adapt rate is 5%.
So all my progressives cost 2 times more and I am only potentially going to satisfy another 5% of my practice. I might as well start stocking pantyhose as I am sure I can also potentially get abotu 5% of the women to buy panty hose from our office. It may sound idiotic, but it should hold true for many offices, I don't think non adapt rates are going to drastically be reduced by these lenses that are optimized with the help of FF processing, heck one could make an arguement that instead of manufacturers using FF processing they could start making BC's in a wider raneg to help reduce errors (instead of 2, 4, 6, 8 make them in 1, 2, 3, 4, 5, 6, 7, 8, 9) this could reduce the error as well. Sure FF processing is a great way of making it possible for the manufacturer to reduce their costs in stocking blanks in all the various permutations that would be necessary in a lens series that had so many BC's.
Another thing I would like to see is the inset, I would want to see that the inset of the lenses and the corridor was palced in such a way that my patient is getting a lens optimized for his/her abiltiy to converge.
If you are afraid that someone is going to reverse engineer your design, I wouldn't worry because it's not your design it's SEIKO's and chances are your competition would already have an idea of your lenses capabilities and they more than likely have more than one map. It would be naive to think that your design has never fallen into the hands of your competition. I am sure the big boys have large databases of various lens maps, I know a few that do just ask your Shamir rep they will show you their lens and their competitors lenses.
I find it disappointing that as an independent lab you are very secretive about all facets of your lens and have even in many cases eluded to that most opticians aren't smart enough for the information, while every month i get articles in various magazines giving infrormation from Zeiss, Essilor, and Scneider. I have always had a tough time with independent labs, in theory I would love to support independent labs but time after time I have been burnt myself except by one and I don't even order many lenses from outside labs especialy the tough ones those are done in house. So for me when I hear trust us, I cringe.
I have in the last two months used the Definity twice and my patients have been plesed. Both case have been high cyl patients and I have another high cyl patient that I will be putting in the Definity as soon as it gets back from the lab and I expect it to go over well also, but I know a bit about the lens and the design. I would love more info, but understand the hessitance of giving away too much, but believe me over time this truth will get out there and the ones that are holding won't be holding our business.
Last edited by HarryChiling; 12-02-2007 at 04:42 AM.
Since the width can change with each design and there are over 2 million possible designs the word approximate is the only accurate way to descibe this. The specific Rx you are asking about will have differences between molded PAL designs: If you want to provide an uncut in the Rx you are talking about, in a material we offer I can then measure each and give you accurate measurements. (the above Rx does not mention Axis which is a critical component.)What's the sum difference between the corridor width of a "molded PAL" and a "fixed molded PAL" in a pl/+1.00 +2.00 +3.00 add?
I'm sorry but your qualifying "appoximate width in the corridor" also can't help but raise my eyebrows.
The last sentence has me going huhn
If this is the last sentance you are referering to; I don't know how to respond other than the complexity of this combined with the proprietary nature of the methods we use to achieve these results is very complex and not easy to explain to someone who has not spent years working with our designs and processes.I also am constantly learning more and more about how to explain the many dynamics to this different approach to lens design and production.
Remember you can check our lenses, just like you verify any other PAL. You don't check the corridor widths on molded designs before despensing.
The process of additional verification is possible but the cost vs. benefit is doubtful in my opinion.
Harry Said:Harry this is not a true statement you have made. You are very smart but don't make untrue statements about another company's products.If you are afraid that someone is going to reverse engineer your design, I wouldn't worry because it's not your design it's SEIKO's and chances are your competition would already have an idea of your lenses capabilities and they more than likely have more than one map.
I have in confidence discussed more details about our designs than I am willing to make public. You are jumping to conclusions with the above statement. We do have the Seiko Succeed production capabilities. The ICE-TECH products are not the same.
Harry said:OK Harry I am 90% sure I will match detail for detail what you received about the Definity. What information did they provide that I am not willing to provide?I have in the last two months used the Definity twice and my patients have been plesed. Both case have been high cyl patients and I have another high cyl patient that I will be putting in the Definity as soon as it gets back from the lab and I expect it to go over well also, but I know a bit about the lens and the design.
As I have said you can order the lenses we produce and if the patient is not satisfied you can return them for fully credit. How much risk are you taking?
Harry said:You are asking for a map of each individualized lens, what map do you want Sphere, or Cylinder? what maps have you been shown? Cylinder or Sphere? Showing a plano with a 2.00 ADD is not showing much.I am sure the big boys have large databases of various lens maps, I know a few that do just ask your Shamir rep they will show you their lens and their competitors lenses.
I really think the only way you are going to be satisfied is to invest in your own lens mapping equipment. You know something about programming and could get this working and solve your problem.
Why not just verify using your current method and let the patient tell you if they have better vision or not. Just a thought.
The solution to lens verification is readily available at a cost of about $40k. While that is not cheap, when compared to the overall investment required to produce backside progressives, it is a no-brainer for any lab doing this type of work. A printer option is available that will print the resultant data as well as a picture of the lens profile.
http://www.visionix.com/site/prod/vm/vm2500.asp?s=all
That is the beginning of a solution for a lab, however there is much more required for the retailer to use such equipment. There is almost none of the equipment for digitally surfaced lenses that is plug and play.
If you know the power 7mm from the optical center to the left, how do you know if this is the correct power? Remember the industry has the opticians checking the Doctor prescribed Rx. There is currently no way for the Doctor to give you this power 7mm from the optical center. So what are you really checking this against at the optical retail level?
I am writing to let you know we have done THOUSANDS OF FREE-FORM LENSES and have never had an issue with any brand except Ophthonix; why do we feel a need to map the entire lens? We don't do this on any other lens we verify! This is no different than as a rep. clients would call and complain the cyl was off in reading area of the progressive. They just needed to verify the distance and put them on the patient.
I know a few producers of free-form do map the entire lens to ensure it was built correctly and the rest will be getting the equipment as volumes increase on free-form.
THE ONLY THING THAT MATTERS IS MY CLIENTS OVER THE PAST 5 YEARS LOVE THE VISION OUT OF THE LENSES!!
I just adjusted a pair of free-form lenses from over 3 years ago and the
client just had a new pair made up north and does not like them as well. Same RX. He is going to get a new RX and a pair in clear, transitions and polarized. That is why the independents need to promote the new technology and look towards the future of the industry.
Just put the lenses on the patient and let them tell you if the RX is correct!
Craig
I agree with Craig, however it is important from a manufacturing QC standpoint to be able to verify that you are in fact making what you think you are making. The ability to print a copy of the finished lens map is an added feature for those dispensers that are interested. Keep in mind that the technology I referenced will also produce a printable map of any progressive, whether it's a "free-form" or a traditional molded design. When a new product or technology is attempting to gain acceptance into the marketplace, it is very often a matter of comfort level with the customer that makes the difference. Remember the first time you heard about shopping "on-line"?
Craig:
Thank you for the confirmation of the concept of using traditional methods to verify.
Unfortunately most of the opticians asking for this additional information have no way to verify the lens surface.
Your point that you have fitted many different brands of these lenses with good results and without any additional equipment confirms that this traditional verification process works.
If the patient can see better, that is the result the optician and the patient should be looking for, not what the power is 8.5 mm from the optical center.
shrimper~dan said:This is for the manufacturer. The retail optician can not really tell that much from the map of the lens. If the retail optician had such a machine they could compare one molded lens for patient "A" with an individualized lens for patient "A" and see the difference in two maps, but the optical surface design is a very complex result of the lens design software capabilities.I agree with Craig, however it is important from a manufacturing QC standpoint to be able to verify that you are in fact making what you think you are making.
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