A.R. Coated Drillmounts

**Mike Fretto** · 01-25-2001, 10:21 PM

Were having a small disagreement here you guy's and gal's may be able to shed some light on. Here's the problem, when faced with a job requesting A.R. coating with tint some of my co-workers feel it best to send for coating tinted in the uncut form. The thinking is, the A.R. will not stick well if applied to an edged and already tinted lense. We use primarilly UTMC. Also with regard to A.R. drillmounts is anyone having trouble with the jig for drilling the Titan frames slipping on A.R. coated lenses .

[This message has been edited by Mike Fretto (edited 01-25-2001).]

**Steve Machol** · 01-26-2001, 01:04 AM

Mike,

Are you saying that you send edged lenses in for UTMC custom coating? This is not supposed to be the case since the backside hardcoat process requires uncut lenses. Would you mind emailing me with more details?

smachol@optiboard.com

(I'm Director of A/R Services for Sola in case you're wondering.)

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OptiBoard Administrator

**Texas Ranger** · 01-26-2001, 01:36 PM

Mike, Any time you're doing AR and tint, you're going to be in trouble, since the AR process has a significant effect on the tint. we do our best to have the coating lab do the tinting, send a sample tint, or have an identical demo lens as the labs. it is also helpful that the pt understand that color in the lens is generally a cosmetic factor and open to perceptual factors, sometimes tinted lens will look different in different lighting even. on drilling the titans, we do many and 95% ar AR, so the basic thing is the double sided scotch tape. do it their way and it works fine.

**Steve Machol** · 01-26-2001, 10:51 PM

Actually I hate to disagree with the esteemed OptiWizard Al :D, but I've done a lot of testing of tinted lenses and AR. The bottom line is that I've seen no difference in AR durability (scratch resistance and adhesion) between tinted and untinted lenses. Note - this is true for cosmetic tints only and not UV tints (as mentioned in another topic.)

The only real problem with tints and AR is the affect the process can have on the tint hue and density. This is particularly a problem with AR processes that use aggressive pre-cleaning. However your AR lab should be able to recommend tinting procedures that minimize this problem.

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OptiBoard Administrator

**Pete Hanlin** · 01-29-2001, 05:18 PM

We do quite a few Titans, and here are the steps I've adopted:
1.) Edge the lenses
2.) Apply blue lensaver tape (used in a surfacing lab) to both sides of the lens
3.) Drill
4.) Send out for AR coat- we use Pentax (sorry Steve :( )

If the lens is gonna scratch, chip, etc., why not do it before having the lens AR coated? Same goes for finishing the lens- might as well do anything that could ruin the lens before having it coated. Also, I swear they're easier on drill bits when they are uncoated.

I used to use a leap pad to hold the guide on for the Titans. However, I find the thickness of the pad causes problems. Now, I just blue tape both sides and hold the guide on with a piece of Scotch Tape. This has worked really well!

Hope this helps,
Pete

PS- I try not to sell tints with AR... simply because you can't really adjust the tint afterwards (I mean, you can, but ;) ). When the patient just has to have a tint, I just tint it a little darker than I want and back it down a bit in the neutralizer. One question for Steve would be concerning Spectralites- I've had more problems with AR adhesion with Spect. than any other material- whussup with that? Is it just the coating company putting the Spectralites in with other lenses and not customizing the coating to adhere to the particular scratch coating on the lens???

**Steve Machol** · 01-29-2001, 05:54 PM

Originally posted by Pete Hanlin:
<FONT COLOR=#FF0000>One question for Steve would be concerning Spectralites- I've had more problems with AR adhesion with Spect. than any other material- whussup with that? Is it just the coating company putting the Spectralites in with other lenses and not customizing the coating to adhere to the particular scratch coating on the lens???</FONT>

I honestly haven't heard of any more problems coating Spectralite than any other material. We (Sola) use the exact same process for Spectralite that we use for CR.

The real answer depends on a number of factors, including but not limited to:

1. The location of the adhesion problem (front, back, both surfaces?)

2. The backside hardcoating coating used. (You should always use a backside hardcoat for A/R jobs, but the A/R lab needs to ensure impact compliance.)

3. The pre-cleaning process used by the A/R coater.

Feel free to call me if your want to discuss this more.

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OptiBoard Administrator

**Texas Ranger** · 01-29-2001, 08:03 PM

Steve, what were you disagreeing with me about? I wasn't questioning the durability of AR on tinted versus untinted lenses, only that it is extremely difficult to match an existing tint for color hue and density, so it's better to send a sample. We only use Crizal, so we can't do the tinting ourselves. But the AR process(all of them) does affect the tint. But,Steve, we're in total agreement! Al.