Digitally Surfaced PALs (Free Form) Clarified

[shrimper~dan]

TECH,
I do agree that the dispenser need not invest in this technology, and I don't see where anyone is asking for it. What I get from this string is that the dispensers are leery of the technology because they don't see any proof of quality control. If one of your accounts, or potential accounts, wants to see that the original design is replicated accurately on the lens they have purchased, and you as the manufacturer can provide them with objective data that does just that, why wouldn't you? And if you are a manufacturer and you do not have the ability to verify the accuracy of your finished product, aren't you running a big risk?
Bottom line is if you are making free-form lenses you absolutely should have a method of verification for QC purposes. There are relatively low cost solutions in the marketplace that will do this, and as a side benefit allow you to show your customers exactly what they are getting and that it meets your quality control standards.

[AWTECH]

TECH,
I do agree that the dispenser need not invest in this technology, and I don't see where anyone is asking for it. What I get from this string is that the dispensers are leery of the technology because they don't see any proof of quality control. If one of your accounts, or potential accounts, wants to see that the original design is replicated accurately on the lens they have purchased, and you as the manufacturer can provide them with objective data that does just that, why wouldn't you? And if you are a manufacturer and you do not have the ability to verify the accuracy of your finished product, aren't you running a big risk?
Bottom line is if you are making free-form lenses you absolutely should have a method of verification for QC purposes. There are relatively low cost solutions in the marketplace that will do this, and as a side benefit allow you to show your customers exactly what they are getting and that it meets your quality control standards.

Yes, from a quality control standpoint you are correct. Without going into all of the potential points for errors with digital surfacing. The mapping is a way to see visually what you have, but to prove the surface is as design, you also need to check the surface with comparision x, y and z data. I don't know how many producers of digitally surfaced lenses use such methods, but I can assure you this is one important part of the QC at ICE-TECH for our digitally surfaced lenses.

[mahmoud.hamza]

hy every body
can some one tell me what is the difference between a freeform progressive lens and a convensional progressive lens :idea: in use!!!!

[NgCognito]

:shiner: I do agree with Uncle Fester. Until I get a simplified non-marketing type answer, I will continue to use Creation, Panamic, GT2 lenses. I don't need all the high tech explanations. I want a simple explanation that convinces my patients that it is worth the additional cost on a lens that might or might not show a significant difference. I have yet to come across a patient that has had or got the new lenses Zeiss individual or Shamir Autograph that saw a marked difference.

[AWTECH]

:shiner: I do agree with Uncle Fester. Until I get a simplified non-marketing type answer, I will continue to use Creation, Panamic, GT2 lenses. I don't need all the high tech explanations. I want a simple explanation that convinces my patients that it is worth the additional cost on a lens that might or might not show a significant difference. I have yet to come across a patient that has had or got the new lenses Zeiss individual or Shamir Autograph that saw a marked difference.

A simple explanation for the ICE-TECH Advanced Lens Technology individualized lenses is a wider corridor and no skew distortion. This is accomplished by managing the off axis error and power errors across the lenses surface.

See the post above by Craig. He has years of experience with many individualized lenses, including the ICE-TECH products and his patients notice the difference. I think other opticians patients may also benefit.

The least benefit will be from low cylinder low power lenses where the potential errors in molded lenses are not as noticable. This technology is not all marketing.

[TLG]

A simple explanation for the ICE-TECH Advanced Lens Technology individualized lenses is a wider corridor and no skew distortion...

Wow, I've never heard that one before. Oh yeah, except for every PAL produced since the original Varilux 25+ years ago:D

[AWTECH]

Wow, I've never heard that one before. Oh yeah, except for every PAL produced since the original Varilux 25+ years ago:D

OK, so you, like others on this board don't believe what a manufacturer says. If you look at the post by Craig, you see a clear statement from a optician user, (such as most of those not believing in what is actually proven to work).

Just curious how to explain Craig's statements????

I don't know why it is so difficult to admit that an improvement is possible.

[TLG]

OK, so you, like others on this board don't believe what a manufacturer says. If you look at the post by Craig, you see a clear statement from a optician user, (such as most of those not believing in what is actually proven to work).

Sorry to offend. My comment was totally tongue-in-cheek. I've been an optician since 1973 and have been witness to the introduction of countless new PAL lens designs. I don't remember a single one that hasn't claimed to have a wider reading zone and clearer peripheral vision. Your comment just struck me as funny because I've read/heard it with every new design. I apologize Allen - I have no ill feelings toward you in any way and I certainly did not mean it as a personal attack. And I certainly didn't intend to demean your product. It's obvious you are passionate about it and I admire (and envy) passionate people.

I don't know why it is so difficult to admit that an improvement is possible.

My greatest hope is that it is possible. Improvement in PAL designs has not grown by leaps and bounds by any means. The improvements are miniscule in my opinion, but I don't think that anything I've posted has suggested that I don't think they could be improved in general. I have worn at least 10 different PAL's, including 2 'Freeform' designs. They all suck. Really. I've worn them every single day for at least the last 12 years. They are a compromise. Yes, I wear them because I don't wanna see the line. But I also wear them because I have tried Flat Tops and Rounds and although my vision was MUCH clearer in each of those, I don't like having to adjust my body position when I want to view near objects at varying distances, preferring to adjust just my head to find the correct area of the progressive instead. We are a long long way from a PAL design that provides the type of vision in distance and near that is anywhere near what the lowly FT28 provides. I respect people like you who have a vision of making them better.

Sorry again to have offended you. Best wishes,

[mahmoud.hamza]

:(:(:(:(:(:(:(:(
Hi frinds

In the TRIVEX test lenses we found a small problem the lenses are liitel bit scratched I don’t know why but it seems like the polishing process was not very good.
Can you please clarify it to me ?and have you an idea about the solution

our machines are OPTOTECH .

I am a little bit afraid because in our future production we are going to focalize on TRIVEX lenses .our sell will be about 30% TRIVEX so the process must be very good and must be Ok.
Thank you

[Fezz]

Here is a link to Younger Optical's Trivex processing page:

http://www.youngeroptics.com/product...techinfo.shtml

And a link to PPG's Trivex info page. They have a valuable download with all of the Trivex processing info.

http://corporateportal.ppg.com/NA/ch...ptical/Trivex/

Good luck.

[mahmoud.hamza]

Here is a link to Younger Optical's Trivex processing page:

http://www.youngeroptics.com/product...techinfo.shtml

And a link to PPG's Trivex info page. They have a valuable download with all of the Trivex processing info.

http://corporateportal.ppg.com/NA/ch...ptical/Trivex/

Good luck.

Fezz
thank you for your replay.
do you please heve any document or information that can help me to know freeform process better because I am a new ingeneer in our company and the other freeform suplier in our country heve more experience then us.
thanks :)

[AWTECH]

I do not know if Optotech has much experience processing Trivex. I know many of there machines are used to produce the Seiko freeform lenses and Seiko does not offer Trivex.

We process freeform Trivex, but we use a very different process than Optotech.

What type of material settings are you trying to use to process the Trivex? With the Optotech polishing machine you may need a different polishing tool to be successful.

What does Optotech say about the polishing problems you are having?

[mahmoud.hamza]

I do not know if Optotech has much experience processing Trivex. I know many of there machines are used to produce the Seiko freeform lenses and Seiko does not offer Trivex.

We process freeform Trivex, but we use a very different process than Optotech.

What type of material settings are you trying to use to process the Trivex? With the Optotech polishing machine you may need a different polishing tool to be successful.

What does Optotech say about the polishing problems you are having?

seiko doas not offer trivex but we have optotech software OEM and it offer TRIVEX
we we use OEM freeform software.
the polishing tool are :
-Polishing strip LP26, 1,27mm,
for polishing wheel Ø70
-FEM-flex. Polishing tool HD25
Ø65mm for Polishing cap
-Polishing Membrane
Ø60 R50 incl. GR35 1.27
-Polishing Membrane
Ø60/100 R50 incl. black felt
optotech did not replay us for this problem yet.
but I know many companys which use optotech machine to produce freeform TRIVEX like TOG from Thailand.

[YrahG]

I know this thread is old, but their is a wealth of information here. What I got from this thread is that their is no QC standard, Darryl mentioned that opticians don't release QC standards to their patients, in my case that is correct and in most cases that is correct, but the QC standard is ANSI and measurements are taken and writen on the work order, these measurements are the fabricated measurements and are compared to the supplied measrements if they meet ANSI they pass and the work goes out to the patient to be dispensed, I think the only reason why I don't give this data to the pateint is becuase no one has asked. It is written and available and if asked for I would provide this information to a patient and even go over the differences and show them how they meet the tolerances we have set in place which conform to ANSI standard.

Here is where I see a difference in the FF lab not provideing any QC data, large manufacturers have built their reputation on the quality of their lenses. Their is a reason why people were using and selling Varilux, Zeiss, Hoya, Shamir, etc blanks instead of genericaly produced blanks from various other manufacturers. With a molded design the PAL surface is verified byt eh manufacturer to meet their standards although this QC data is not available the reputation of these companies was built on the quality of these lenses which is a reason why ECP's choose these brands. The lab takes these blanks and further processes a prescription surface onto the back and then verifies that this combined optical system meets the necessary tolerances ANSI at 3 point DRP, PRP, and NRP additionally the blank may be sagged at the surfaceing department but often times the lens is processed in most labs without the need for sagging the lens. So at the optician level this lens has been through 3 QC processes along it's production:

1. PAL surface at the manufacturer
2. Prescription (combined optical effects at DRP, PRP, and NRP) at the lab
3. Prescription (combined optical effects at DRP, PRP, and NRP) at the dispensary

The digitally surfaced process is created all at the lab, so even though a Zeiss, Varilux, Hoya, or Shamir design is licensed. The manufacturer does not directly verify the surfaces. So the QC process is:

1. Design at the lab
2. Prescription (combined optical effects at DRP, PRP, and NRP) at the lab
3. Prescription (combined optical effects at DRP, PRP, and NRP) at the dispensary

The process is not much different except that the manufacturer of the design is now the lab, combine this with compensations, compensated Rx's being supplied in 0.01D, and the need for smaller aperature digital lensometers for proper verification and the dispenser is left without an adequate way to verify the lens and the manufacturer/lab would have no vested interest other than sales of the product to accurately verify the design and Rx.

Now I know labs that misplace returns and credits accidentaly on purpose, this is not the kind of lab that I would trust with my FF lens production. Our profession is based on science not faith, so I prefer their be some form of verifiction other than faith available to the dispenser. This means that somewhere along the line ECPs need to adopt more accurate equipment that can verify these lenses, for the time being I have a lab that I trust that uses sophisticated equipment in their verification process, they are family owned and have built a reputation on quality before FF came out. I will trust them until a better way to verify comes along.

[AWTECH]

Now I know labs that misplace returns and credits accidentaly on purpose, this is not the kind of lab that I would trust with my FF lens production. Our profession is based on science not faith, so I prefer their be some form of verifiction other than faith available to the dispenser. This means that somewhere along the line ECPs need to adopt more accurate equipment that can verify these lenses, for the time being I have a lab that I trust that uses sophisticated equipment in their verification process, they are family owned and have built a reputation on quality before FF came out. I will trust them until a better way to verify comes along.

There is verification possible today.

Our designs have specific information to verify to. We check this with every lens. Does that mean that a mistake will not be made. No

Computers can crash, humans can make mistakes, but in our facility we pride ourselves in have some to best digital surfacing and/or freeform knowledge and capabilities. Our related company Advanced Lens Technologies, LLC develops and consults with companies around the world on freeform and freeform processes.

[Darryl Meister]

What I got from this thread is that their is no QC standard, Darryl mentioned that opticians don't release QC standards to their patients, in my case that is correct and in most cases that is correct, but the QC standard is ANSI... I think the only reason why I don't give this data to the pateint is becuase no one has asked. It is written and available...

We are talking about two very different things.

The ANSI Z80.1 standard is obviously a public document, which your patients could obtain with minimal effort. However, the ANSI Standard tolerances are not the results of a quality audit or inspection, they are the guidelines for conducting one. Providing these guidelines in no way indicates how close a given pair of eyeglasses is to them.

Eye care professionals generally don't submit a report to their patients listing the measured value against each guideline in the ANSI Standard for every pair of eyeglasses, nor do laboratories submit such a report to eye care professionals. At each stage of the supply chain, we only pass it on to the next if we feel that the product meets our own quality guidelines (i.e., the eyewear "passes" inspection).

But the proposed scenario of providing a detailed analysis of the lens, while not without its merits, still assumes that eye care professionals would "take the laboratory's word for it" anyway once they receive a report, contour plot, or whatever from the lab, especially without extensive training in the interpretation of the results. And ECPs are still responsible for independently verifying the results for themselves.

I have no doubt, however, that such a quality assurance system may eventually become the new standard of lens inspection someday, as free-form lenses become more pervasive and digital inspection devices become more affordable, but it will involve a pretty steep learning curve.

[AWTECH]

Darryl said:

I have no doubt, however, that such a quality assurance system may eventually become the new standard of lens inspection someday, as free-form lenses become more pervasive and digital inspection devices become more affordable, but it will involve a pretty steep learning curve.

I agree with the above post. In addition I would like to add that I believe the Optician inspection detail that is still being performed is a bit overkill today. I think the correct measurements for fitting are very important but the number of incorrectly made lenses from quality run facilities getting past the internal verification is very few.

It would be interesting to have a study that would check the glasses for patient fit only then see how many patients complain, and see what percentage is due to lenses getting past the final inspection and verification where they were made. I think the percentage shipped that were incorrectly processed is very low. My guess is there will many more errors such as, Rx wrong, or PD not right etc.

The quality control for lenses today by quality labs is pretty good. With lens mapping measurement equipment being available that can be set with specific go or no go settings, lenses can be acurrately verified before leaving the facility where they were produced. This is an excellent way to verify freeform lenses, then the only final check is the PD, and height and alignment of the engraving marks so that both lenses are on axis. (If the marks are engraved after generation the chance of the design being off axis is almost non-existant.

[Barry Santini]

Isolated inspection and verification of finished eyewear, even using advanced technology for QC ensurance, can only...at best, IMHO, ensure that the eyewear has a chance to be considered "adequate".

It can never be excellent, when it is divorced from dispenser/client interaction and experience.

Moving the public to love the idea of wearing eyewear...prescription or not... is not within the payscale of a lab or online delivery.

ANYONE who thinks that "correctly-made" eyewear is all about what goes on just at the lab level, is, again - IMHO, naive about the complete eyewear experience.

Adequate is NOT excellent. Never has been. Never will be.

Choose your weapon.

Barry

[Fezz]

Great thread!

Lots of valuable information!

:cheers::cheers::cheers:

[YrahG]

I have no doubt, however, that such a quality assurance system may eventually become the new standard of lens inspection someday, as free-form lenses become more pervasive and digital inspection devices become more affordable, but it will involve a pretty steep learning curve.

Agreed, there has to be a set standard that will be accepted for the verification of FF lenses on both ends the dispenser and the laboratory. I pointed out ANSI in my post to show that a concrete standard for a tolerance exists and it is transparent. My lab doesn't supply me with any specific data because I can just as easily check it, but they do tell me that "all lenses meet or exceed ANSI" and they supply me with an ANSI summary at my request. In contrast with FF their exists no standard to check against and I fear that ANSI is not adequate, with no standard each laboratory is free to make up their own, which is fine, but their is no information available to me the dispenser as to what this standard is or a way for me to feasably check it against this standard if one existed. This technology is still feeling growing pains, still has issues, and still has room for improvement still very fascinating.

As an example if I was to throw ANSI out the window I could reduce the cost of lenses by a certain percentage since their would be no failed lenses. An OMD on this board was just suggesting this very same principle regarding prism tolerance as a means to save a few dollars. With more and more labs offering FF lenses their needs to be a way to verify lenses as competition increases the margins on the product get cut and we'll start to see a rash of poor quality masquaradeing as precision. Also with the ability of every lab to create their own design I don't want to see 1970's PAL tehnology processed with FF start flooding the market. That's just not what I want.

[YrahG]

Isolated inspection and verification of finished eyewear, even using advanced technology for QC ensurance, can only...at best, IMHO, ensure that the eyewear has a chance to be considered "adequate".

It can never be excellent, when it is divorced from dispenser/client interaction and experience.

Moving the public to love the idea of wearing eyewear...prescription or not... is not within the payscale of a lab or online delivery.

ANYONE who thinks that "correctly-made" eyewear is all about what goes on just at the lab level, is, again - IMHO, naive about the complete eyewear experience.

Adequate is NOT excellent. Never has been. Never will be.

Choose your weapon.

Barry

Nicely put, I of course advocate precision on the part of the dispenser as a prerequisite to any eyewear experience. Thank you everyone lots of great replies and comments, they keep the juices flowing.

[AWTECH]

YrahG

Also with the ability of every lab to create their own design I don't want to see 1970's PAL tehnology processed with FF start flooding the market. That's just not what I want.

I don't know what how you think this will happen. Designing a PAL for freeform use is not a simple task.

Don't think that only the big name companies can create great lens designs. People create, whether they work for a large company or small one.

[YrahG]

YrahG

I don't know what how you think this will happen. Designing a PAL for freeform use is not a simple task.

Don't think that only the big name companies can create great lens designs. People create, whether they work for a large company or small one.

Agreed, but that same philosophy applies to people cheating. People cheat, wheather they work for a large company or small one.

I hope you don't get the impression I am talking about your company, I have had no dealings with you to base anything off.

[AWTECH]

Also with the ability of every lab to create their own design I don't want to see 1970's PAL tehnology processed with FF start flooding the market. That's just not what I want.

I was only pointing out the fact that a great deal of good products are available from smaller companies. In fact there are many smaller companies providing products and services to the big companines. Then the big companies market these products under their own name. (But that is true with many industries)

[YrahG]

I was only pointing out the fact that a great deal of good products are available from smaller companies. In fact there are many smaller companies providing products and services to the big companines. Then the big companies market these products under their own name. (But that is true with many industries)

Agreed. I wish more specifics were available, but that's business.