Damn spots, they're all I see

June 29, 2015 3:59 AM

My last two pairs of glasses have ended up with tiny spots on the lenses. Two different optometrists/opticians have said they don't know why. Do you?

In the past three years I've had two pairs of glasses that have developed tiny spots in the anti-scratch coating. They are little round spots, across the whole lens on the eye-side, where the coating has vanished, like little bubbles. They're tiny, like half a millimetre across at most but there are hundreds on each lens. There are fewer near the top, where the lenses come close to my browbone, and near the bridge.

I only clean my glasses with a microfibre cloth. I don't use weird chemicals, either directly on my glasses or in everyday life. The only thing I can think of that would cause the coating to bubble off is steam, and the only exposure they have to steam is when I'm showering and leave them on the bathroom counter.

Both my NZ optometrist and my Swiss optician have said they don't know what might be causing this. Over time, it means visibility isn't as clear. I'd like to know the cause so I don't lose yet another pair when I next order new glasses!

Oh, and a PS: I have a pair of prescription sunglasses that I ordered at the same time as my last pair, and they are fine. Of course, I probably wear them a tiny fraction of the time compared to my main pair, which I wear all the time except when I'm asleep.

posted by tracicle to Health & Fitness (8 answers total)

Do you clean your glasses while wet or dry? If you get grit on them and are rubbing it around - no matter how great the cloth - it'll scratch the coating. Microfiber is great for oil and for not leaving any streaks, but any dust may end up scratching it if you use much pressure.

Try rinsing them with water first, then rubbing them lightly with the microfiber to dry - think "polishing" rather than "cleaning". If you have to scrub at all, rinse more.

Some of the microfiber sets I've gotten have come with a tiny spritzer bottle of what I think is rubbing alcohol. Adding moisture before cleaning will give it a layer of lubrication for any dust/dirt/particles between the cloth and the glasses.

I ended up getting laser eye surgery (OMG WORTH IT), so now I only have problems like this with sunglasses.
posted by bookdragoness at 4:19 AM on June 29, 2015

Best answer: I had this happen to the anti-glare coating with glasses I got in Masterton. I went to a new optometrist in Palmerston North a year or so later, he took one look and named where I got them from, followed by yeah, I've seen poor quality work like this a lot from that place. So it seemed, in my case anyway, to be an issue with the coating not being done well rather than anything I did. It was just basically lifting off one tiny bubble at a time. I had it stripped off completely and the glasses were fine for a couple more years until my prescription changed (just more glare). I've also had other glasses with anti-glare coating since and never had this problem despite being treated exactly the same (including having them live in the bathroom) so *shrug*.

The last lenses I got came with a several year warranty on the coating so maybe that's an option to look for if possible? It made me feel better any way.
posted by shelleycat at 4:20 AM on June 29, 2015 [1 favorite]

Yeah I paid a ton for anti glare coating and it did this consistently until I changed opticians. Now I have glasses from 6 years ago that are still fine.
posted by janey47 at 6:21 AM on June 29, 2015

All my old glasses with anti scratch coating, no matter where I got them, look like they were nibbled on by glasses termites. My brand new glasses have no such coating, nor the anti-glare, and they are clear as day and wonderful. I won't be wasting money on coatings ever again.
posted by poffin boffin at 6:27 AM on June 29, 2015

I specifically never get coatings on my glasses now because that would always happen to mine. I assumed it had to do with being in a chemistry lab and having them get occasionally exposed to vapors from organic solvents. The places I've gone to have seemed unsurprised by that line of reasoning. I'm not sure if it's relevant to your glasses or not, though my sunglassses with coating are also fine because I don't wear them at work.
posted by tchemgrrl at 6:32 AM on June 29, 2015

I used to work in wholesale optical/lens manufacturing. It has nothing to do with you and how you clean your lenses. The coating process is tricky because a lab is coating blanks, and it sounds like they coated a bad batch or coated a batch poorly. Usually when it's tiny spots, it's an indicator that the ultrasonic cleaner at the facility isn't working - that was our "tell" when we needed to get it serviced, little spots on the lenses we coated. Sometimes it's the autoclave/heater, which doesn't dry all the water spots before coating. If you're getting little spots of AR coating coming off your lenses, there are practically no household solvents or otherwise that would cause that kind of damage. It's not you.

Next time, get lenses with a manufacturing warranty. If it happens again, you should be able to take them back to the shop and say, "My AR coating was applied poorly, and I'd like it redone at your expense or the lab's expense."

For what it's worth, different blanks seemed to be associated with more frequent defects. I personally prefer Zeiss lenses whenever possible when I'm getting coated lenses, and I ask for them by name.
posted by juniperesque at 7:44 AM on June 29, 2015 [5 favorites]

I had a pair of glasses develop this problem and I used Armour Etch to remove the coating. Worked really well.
posted by Mid at 11:53 AM on June 29, 2015

Up until the mid 90s, I was able to get quartz coated plastic lenses that were virtually indestructible.

Several opticians have told me that the inferior anti-scratch coating I've gotten since then IS quartz.
posted by brujita at 11:20 PM on June 29, 2015