Edging Anti-Fog Lenses?

[dragonquest]

Since the pandemic we have had an increase in interest in the anti-fog coatings for our lenses. However, these lenses have proved to be an absolute nightmare for our back of house lab. Every time we try to edge the lenses down they come out of the machine with black imprints in the shape of the edger clamp on the backside. The edger clamp is a black rubber so it appears to be the black dye of the rubber itself imprinting itself onto the antifog coating. Beyond this, you have to be incredibly careful marking the lenses up (you can only mark them up on the front side) or even cleaning them because the backside coating is damaged very easily. The specific coating in question is the Essilor Anti-Fog AR. I believe the Crizal Avance w/ Optifog doesnt have these issues, its more like a traditional AR, correct?

How do you guys edge these lenses? Or do you not even bother and send it off to a lab? Also, how do you clean these lenses?

[bta89]

We have tried tons of anti-fog stuff. Honestly the best stuff, lens and spray, that we have tried has been the Zero Fog Plus from Luxottica. We got a sample from our Oakley rep and while it's not 100% perfect, it is by far the best. I've sprayed it on my glasses and had it last up to 4 days before having to clean my glasses.

[NAICITPO]

Since the pandemic we have had an increase in interest in the anti-fog coatings for our lenses. However, these lenses have proved to be an absolute nightmare for our back of house lab. Every time we try to edge the lenses down they come out of the machine with black imprints in the shape of the edger clamp on the backside. The edger clamp is a black rubber so it appears to be the black dye of the rubber itself imprinting itself onto the antifog coating. Beyond this, you have to be incredibly careful marking the lenses up (you can only mark them up on the front side) or even cleaning them because the backside coating is damaged very easily. The specific coating in question is the Essilor Anti-Fog AR. I believe the Crizal Avance w/ Optifog doesnt have these issues, its more like a traditional AR, correct?

How do you guys edge these lenses? Or do you not even bother and send it off to a lab? Also, how do you clean these lenses?

I edged one pair of them and that was enough for me, I send them to the lab now. It's worked out, but we don't do a ton of anti-fog lenses. Most people just understand that there is no end all be all solution to the fogging problem.

I believe the optifog AR is more like a regular AR with those activation clothes, looks like an AR on both sides front and back. The Essilor Anti-fog when I clean them feels like the back of the lens is roughed up so air won't stick to it maybe? From what I remember it looked like AR only on the front side. Would love for a lens guy to go through how the anti-fog lenses are supposed to work.

[Alex Camblor]

3m blue chip lens protectors on the backside of the lens will avoid stains from the clamps, but I have always found those types of fog coatings to be more trouble than they are worth. They are too vulnerable to stains and you end up eating the cost of remakes if you happen to get ink on it and you're going to have unhappy patients if they end up staining it right after its dispensed.

Dynamic labs Fog Stopper works pretty well but does need to be reapplied every few days. At least you and the patient dont have to worry about messing up an uber-fragile fog coat with a little bit of ink.

[DanLiv]

I believe the optifog AR is more like a regular AR with those activation clothes, looks like an AR on both sides front and back. The Essilor Anti-fog when I clean them feels like the back of the lens is roughed up so air won't stick to it maybe? From what I remember it looked like AR only on the front side. Would love for a lens guy to go through how the anti-fog lenses are supposed to work.

Anti-fog works by lowering surface tension of water droplets so they "wet" the lens, i.e. spread out over the lens instead of beading up. Ironically that is exactly the opposite of what good hydro-/oleophobic ARs do; they enable and increase in surface tension of fluids through a very smooth surface which creates the "low contact angle" they keep talking about. This encourages fluids to not wet the lens and sit on the surface and be able to slough or be easily wiped off instead. However, this is the perfect surface for fogging. The anti-fog fluids and wipes basically just leave a residue that breaks up the smoothness of the surface and encourages wetting. The anti-fog coatings are somewhat hydrophylic so fluids stick to and wet the lens instead of beading up into a fog, but that also has the side effect of making the lenses feel less smooth, and they are an absolute bear to clean. You though cheap ARs are had to clean? Those anti-fogs are worse. I've dispensed a few Crizal Optifog and they are so bad I do not use them anymore. Essilor also does Optifog with TD2 hardcoating and that's not bad, no more difficult to clean than uncoated lenses.

[NAICITPO]

Anti-fog works by lowering surface tension of water droplets so they "wet" the lens, i.e. spread out over the lens instead of beading up. Ironically that is exactly the opposite of what good hydro-/oleophobic ARs do; they enable and increase in surface tension of fluids through a very smooth surface which creates the "low contact angle" they keep talking about. This encourages fluids to not wet the lens and sit on the surface and be able to slough or be easily wiped off instead. However, this is the perfect surface for fogging. The anti-fog fluids and wipes basically just leave a residue that breaks up the smoothness of the surface and encourages wetting. The anti-fog coatings are somewhat hydrophylic so fluids stick to and wet the lens instead of beading up into a fog, but that also has the side effect of making the lenses feel less smooth, and they are an absolute bear to clean. You though cheap ARs are had to clean? Those anti-fogs are worse. I've dispensed a few Crizal Optifog and they are so bad I do not use them anymore. Essilor also does Optifog with TD2 hardcoating and that's not bad, no more difficult to clean than uncoated lenses.

Thanks, great information!