Difficult to receive "perfect" lenses with AR coating?

**audelair** · 03-19-2004, 08:41 PM

I received my first Transitions lenses with AR coating recently, and am very pleased with them.

There is some kind of a scuff mark on it that is irremovable, however (i.e., i tried cleaning it). it is almost impossible to see outdoors or by the window. But it is easy to see indoors, around any electric light, especially looking at it at an angle against a dark background. it is still detectable looking at it straight on depending on the lighting.

basically it is about the size of a thumbprint. but it is more of a scuff than a smudge, as i can see distinct scratch lines.

i'm guessing this is in the AR coating?

It was like this when i received it, as I noticed it before I had made any contact with the lense.

The good news is that I can't notice it at all when i am wearing the glasses. It is only noticeable when I take them off and examine them.

My question is whether these types of blemishes/imperfections are normal and acceptable? Is this a sign of a poorly applied AR coating, and is it worth taking it back to get replaced? I bought this from a high-end private optometrist.

Thank you for any feedback/advice you can offer.

**Stopper** · 03-19-2004, 08:52 PM

Not sure what it is but I would take it back for inspection and explaination. I'm sure they would like to know if you are having a problem so they can help.
:cheers:

**audelair** · 03-19-2004, 09:53 PM

actually i took it back immediately and we were unable to see see the scuff. the store has full size windows all around so it is very bright there and hard to see any scratches. i didn't want to waste too much of their time, so i told them it's no big deal. of course as soon as i leave the store and go back into my car, i see the scuff again :D

like i said, the scuff is very minor. does AR scratch very very easily? this is a pretty top optometrist, so i'm guessing they used one of the better AR's. if it's just a light surface scuff that maybe the optometrist caused using the microfiber, then it probably isn't a big deal, since it's minor (almost undetectable looking at the lens straight-on). i just wasn't sure if extremely fine scuff marks on a new lens is a sign of a bad AR job.

The reason it is a bit odd to me is that it is not really a scratch as it is a patch. imagine running sandpaper across it using your thumb's pressure. that's what it looks like except extremely light (barely noticeable).

thanks for the input.

**Cowboy** · 03-19-2004, 10:07 PM

Aude,

Honostly, if your optician respects the quality he puts out, he will replace it if you have concern. As a consumer, you should not sacrifice for second best. You paid top dollar (I am assuming) for these glasses, and you should receive them free from imperfection. You would not accept a lexus with scratched paint or torn seats, would you? Take them back and ask to have it replaced. In most cases, the lab that produced the lens would likely replace it for the optician, so you would not be putting him out either. If you were my client, I wouldn't have even asked you to prove the smudge existed, it would have been replaced without question.

But, thats just me.

:cheers:

Cowboy

**mrba** · 03-19-2004, 10:19 PM

Typical Engineer! Our most scrutinizing customers by far. Hard to tell if they aren't perfect without looking at them, but by all means take them back to where you got them and then relax.

My Dog told me today that life is too short.

**chip anderson** · 03-19-2004, 10:44 PM

If you don't notice it at all when wearing the lens, and others don't notice it when you are wearin the lens, why do your care?

Chip

**audelair** · 03-19-2004, 10:54 PM

Cowboy said:
Aude,

Honostly, if your optician respects the quality he puts out, he will replace it if you have concern. As a consumer, you should not sacrifice for second best. You paid top dollar (I am assuming) for these glasses, and you should receive them free from imperfection. You would not accept a lexus with scratched paint or torn seats, would you? Take them back and ask to have it replaced. In most cases, the lab that produced the lens would likely replace it for the optician, so you would not be putting him out either. If you were my client, I wouldn't have even asked you to prove the smudge existed, it would have been replaced without question.

But, thats just me.

:cheers:

Cowboy

thanks for the feedback. luckily i have a year's warranty on this, so if i find that it really bothers me, i'll talk to him about it :)

**audelair** · 03-19-2004, 10:55 PM

chip anderson said:
If you don't notice it at all when wearing the lens, and others don't notice it when you are wearin the lens, why do your care?

Chip

as stated in my first post, the ultimate question is: "Is this a sign of a poorly applied AR coating, and is it worth taking it back to get replaced?"

**For-Life** · 03-20-2004, 12:28 AM

The coating is crazed. It is not necessary a bad coating, probably just an unlucky thing. But I do agree that you should get it replaced.

**paw** · 03-20-2004, 12:37 AM

Yes, it's worth it to get it replaced. I don't know if it was poorly applied, or got scratched after application.

Either way, the patient should never receive lenses that have a noticable imperfection. If you notice an imperfection upon receipt of the lenses, take it back. You paid for "perfect" lenses, so make sure you get "perfect" lenses!

Take the person outside, if it makes you feel better, to show them the scratch, or go there when they tend to be less busy, so you don't feel pressured about "wasting" their time.

AR coatings are really nice to have functionally and cosmetically, and you should feel confident wearing your AR coated lenses, without worrying about a scratch.

**Eddie G's** · 03-20-2004, 07:38 AM

MRBA, you're soooo right!

:cheers:

**Cowboy** · 03-20-2004, 08:31 AM

Eddie G, MRBA,

Don't rag on the guy. He had a legitimate question and it should be anwered professionally, not personally. Just because he is an engineer does not make him an more or less "scrutinizing" as you or I. Remember, we are consumers outside our jobs and those service people could be saying the same about you.

:finger:

Cowboy

**Bev Heishman** · 03-20-2004, 12:26 PM

I have had to replace several AR coated lenses with a problem similar to this. I could only see it under a spotlight in my dispensary. The patient had a lot of problems especially at night. It does not appear sometimes until a day or two goes by. Ours was from the chuck pressure from edging the lens even though we use 3 mm blue dots to protect the surface. It starts small and some times invloves more area.:)

**JRS** · 03-20-2004, 02:28 PM

If his "scuff" mark looks like a circle (ie. thumbprint) and it is centrally located, it is most likely a chuck pressure mark. I did not see his Rx, but I would guess it's a thin-centered lens.
If it is to one side, and seems to be located on the ocular side, it could be bad adhesion of the applied rear coating.

Engineer - is the thumbprint about the size of a dime and located near the center of the lens?

**audelair** · 03-20-2004, 03:48 PM

yep, it is the size of a thumbprint (the size of a circle with several horizontal 'scratches'), near the center. the prescription is -5.00, and they were the high-index transitions.

thank you very much for all of the feedback and information. if it will get worse, i may have to get it replaced.

and i am pretty scrutinizing. however, the first time i saw it i was merely looking at it, and was by no means "inspecting" it. i just happened to be in the right lighting or something. ever since then, i have been scrutinizing it pretty hard (can't help it!).

so i guess it's a chuck pressure mark? will it cause any longterm problems with the lens? thanks again for all the information, you've all been very helpful.

**For-Life** · 03-20-2004, 04:00 PM

audelair said:
yep, it is the size of a thumbprint (the size of a circle with several horizontal 'scratches'), near the center. the prescription is -5.00, and they were the high-index transitions.

thank you very much for all of the feedback and information. if it will get worse, i may have to get it replaced.

and i am pretty scrutinizing. however, the first time i saw it i was merely looking at it, and was by no means "inspecting" it. i just happened to be in the right lighting or something. ever since then, i have been scrutinizing it pretty hard (can't help it!).

so i guess it's a chuck pressure mark? will it cause any longterm problems with the lens? thanks again for all the information, you've all been very helpful.

It could spread throughout the lens and become far more worse. The lens is probably Airwear Crizal with Transitions. I have had chuck marks appear a couple of times when I have used that lens, probably only half a percent of the time. It can be caused by too much pressure on the chucks or if the chuck is removed by ripping it off the lens instead of twisting it, or it could just be a defect. Get it replaced. Most dispensers want you to come back in a situation like this, because it allows us to fix mistakes before they happen again.

**audelair** · 03-20-2004, 05:45 PM

For-Life said:
It could spread throughout the lens and become far more worse. The lens is probably Airwear Crizal with Transitions. I have had chuck marks appear a couple of times when I have used that lens, probably only half a percent of the time. It can be caused by too much pressure on the chucks or if the chuck is removed by ripping it off the lens instead of twisting it, or it could just be a defect. Get it replaced. Most dispensers want you to come back in a situation like this, because it allows us to fix mistakes before they happen again.

thanks very much, i'll go get it replaced asap :)

**Clive Noble** · 03-20-2004, 11:17 PM

I'd also say it was chuck pressure or 'drag' from the roughing wheel against the chuck, maybe there was a fault in the application of the hard coat.

100% take it back, make sure the dispenser sees the fault and knows what you're talking about.

**mrba** · 03-21-2004, 03:51 AM

Cowboy,

"our most scrutinzing customers by far" is a tactful way of saying a customer is picky, resenting that fact out of lazy selfishness, and yet respecting thier higher standard.

You say

..."Just because he is an engineer doesn't make him more scrutinizing"...

Wrong. Having dispensed in the silicon valley, I can assure you I have dispensed more engineers in one week than most do in a lifetime. They are by far wayyyyyyyy more picky. No question. And its not even a generalization. Its a fact (not a rag on). I have a customer in Mt. View (that uses my lab), and writes ENGINEER on every such order!

Having said all that you don't need to be an engineer to want a bad job re-done.

That was my professional opinon thank you, and I stand by it.:hammer:

**rsandr** · 05-01-2004, 04:24 PM

Engineers are picky.
I had one giving me a b*ll*cking because a top hat washer on his wife's rimless wasnt up to scratch, he could see the tag where it had been broken off the pack.

The words 'faulty flange' often raise a titter when i remember the conversation.

**Pete Hanlin** · 05-03-2004, 07:43 AM

As JRS, Clive, and others have pointed out, the mark is almost certainly from either a.) too much chuck pressure during edging, or b.) a mismatched chuck and block during edging.

Just as a general word, if you edge lenses in your office and have noticed this problem (looks almost like fog in the center of the lens- under magnification it appears like a spider web), have your edger updated to handle thin AR coated lenses.

Also, when you are deblocking, twist the finishing block off (with pliers designed for that purpose). "Peeling" the block and pad off with your thumb can create a small line of crazing in the lens periphery.

Finally, if you have an air-heated frame warmer in your office, do not use it on frames that have AR coated lenses mounted. You will probably craze the AR- you might not notice it, but the patient eventually will.

**For-Life** · 05-03-2004, 08:47 AM

I wanted to add from my experiance with one of the newer machines. I have the Delta and I had been getting chuck marks when I did larger frames, but not smaller frames. What was happening is when the machine tells you to use a larger chuck, it takes the lens down in one step, for a smaller chuck it would take it down in steps. So I now take down my larger poly with AR down in steps. Just to help if someone has similar problems.

**Jedi** · 05-03-2004, 01:17 PM

A tip that one of my lab tech gave me for "seeing" crazed coatings is to hold a lens against ( a couple of feet ) a black surface, then rotate the lens, a better alternative than "hunting" for it.

**drk** · 05-03-2004, 01:26 PM

Hey, I swear that I've seen this before too, but it was off-center. It really did look like a fingerprint that was on the lens surface before AR coating was applied. Is that possible?

**edKENdance** · 05-03-2004, 09:53 PM

Unfortuantely I've learned to find crazed coatings on lenses quite a bit recently. What we finds works the best is to hold the lenses at intermediate distance in front of a bright light source looking at the front of the lenses. Tilt the lenses away from you and they show up quite clearly and almost look like a smudge. We edge with spartans and have only seen this happen with our poly/ar's.

For fun you can intentionally craze a defect and train yourself to see it really quickly. The un-fun part is trying to craze the defect again and again and not being able to do it.