AR lenses... And me.

They drive me up wall, it's just like oleophobic coatings.
Always attracts finest lint particles and dust, and some look greasy.

Fenix, I'm looking at you, I really dislike your AR lenses. On my other lights like Olight, if I carnauba the lens, it's evident.
I just like it OK, phones, tablets, I wax many things.

Try and wax or keep a Fenix lens dust free'ish.
They look like crap all the time, dusty and streaked.

True it's kept cleaner by that coating yes of mud and oils, but I clean that off myself easily enough, it's kind of obvious when needed.
When waxed, most contaminants don't stick to it as easily, and lens looks great.

I wax glass on my vehicles too ftr. I like high surface tension and byproduct of shininess.

So, now AR is my pet peeve being a slight clean freak of my tools.
Does AR bother you at all?
I never even touched on the hue's it can cause, I also think it's not the cats pajamas for maximum clarity even if science says otherwise.
I want to see the Wave of light from behind my light, and twin electron trails clearly from the sides. I see this on other lights nicely.
I believe the AR slightly diffuses beam profile and clouds this effect.

Though my thought to ask all of you is, and I hope this kind of makes sense to someone,..
does that tinted coated glass bother you?

Anyone tried Rain X on a lens? As far as dirty lenses, my ZL SC52d is my worst offender as the way I carry it I must touch the lens to get it off of my belt.

I try to ignore the grease.

I've used rain-x on a few, the hotter ones can cause yellowing tho.

That's got to be the silicones turning yellow, repels moisture, attracts dust and smoke and ages.

The AR coating is there to increase the amount of light getting out of the light. I don't find it attracts dust, I just notice the dust more because the glass looks more transparent. I like the AR coating, if nothing more than to get another 5%-10% more output.

We build high precision lens assemblies from a few hundred to many thousands of dollars in price. The coatings we most often use are MgF2 and though not impossible to damage are very tough. We never use a polish of any kind on a lens. The correct or appropriate cleaner should be specified by the manufacturer of the assembly (in this case the flashlight). We typically use a reagent grade solvent like acetone or IPA but it depends on the adhesive or material adjacent to the lens. Acetone will melt plastic and smear some O-Rings, ISO can breakdown some adhesives and smear those on the optic. Contact the manufacturer for a recommendation before you use a solvent (!). WalkIntoTheLight is correct about the increased output.

I'm sure you guys are correct.

Still I will always feel if the glass is lighting up, it's diffusing.
I've other lens that do not light up like these AR coated ones in particular.

I want all the light out, in all directions not just a range of degrees.
If it's to wean reflected, it's weaning output.
To myself these coatings belong on cameras and displays, not on a photon blaster where every possible electron counts.

About attracting dust, it's a joke how much faster it accumulates on this glass versus others. If it does appear dusty, it is, if it glow, it's capturing.

Go to just about any good camera sales store and purchase a few of their lens cleaning pens and microfiber cloths.

The pens have a fine hair brush on one end and a coated suction looking cup on the other. Just use the brush. The microfiber cloth isn't recommended for removal of oil or grease, but the clean a lens and leave no lint.

That's what I use now too, from my real old canon.
I'll try an get pictures of one that does not gather it out of the air and one that does badly. May be hard as it's only visible lit.

dude! Im an optician and have dealt with AR coatings for a dozen years. Stop the waxing etc! Most flashlight lenses use cheap AR just go to any Lenscrafters and buy a lens cleaning kit. Lens cloth plus spray should do you fine. For really stubborn dirt etc use rubbing alcohol and a Q-tip then go over with spray. You will never get the cheap AR coatings spotless. I must admit that Armytek has by very far the highest quality easiest to clean AR coating on their lenses in the industry love the green sheen they have. Dont let the AR on the vast majority of lights drive you up the wall! Dont expect to be able to keep them spotless as they are not meant to be able to be kept spotless its just their to help light transmission efficiency...

I would not recommend rubbing alcohol or any product from the personal care department for cleaning a lens. ISO (Isopropyl Alcohol) and in particular reagent grade ISO are not the same thing as rubbing alcohol just like reagent grade acetone and fingernail polish remover are not the same even though in each case they are the same base chemical. For the cosmetic products they add perfumes and dyes that will leave deposits on the lens coating or in some cases may damage the coating by staining it. Eyeglasses are a very specialized field (and I tip my bottle bottom glasses to you for doing it for a living) but the applications are different than illumination optics and so are the cleaning methods.

Isopropyl then for the tough stuff. Acetone may or may not crack the lens depending on if the lens has been hard coated and then treated properly I only use it to remove progressive lens markings on already ground and treated lens blanks. I seriously doubt these light lenses are hard coated acetone will most likely instantly cause it to crack. I use eyeglass spray cleaner and a lens cloth. For tough stuff isopropyl works just fine. Never had a bad reaction in a light lens. Ty for the hat tip. Rarely do I have to break out the alcohol. If spray cleaner and a good lens cloth doesnt "get it" then its something thats permanent. Keeping all the eyeglass lenses clean that I have to deal with drives me up the wall enough I know better than to freak over my light lenses although I seriously wonder why the big LED light makers dont offer high end hard coat based/teflon based hydrophobic/oleophobic AR coatings on their lenses for an up charge hell Id buy it. Idk exactly what mix Armytek uses but its the toughest most resistant AR coating Ive ever seen on a light lens.

What do you think of Olights lens?

I have 4 Olights both M2X and M3X Javelots, the R40A and the SR52. All 4 have very thick very well manufactured optical grade glass and above average AR. Love the blueish very evenly and properly applied purple sheen to their lenses. Havnt had to spray any of them theyve all proven hydrophobic, oleophobic, highly scratch resistant and super easy to lightly wipe clean with a lens cloth. Trying to remember where I saw it but the lens on the SR52 is something crazy like 3.5-4mm thick which is excellent. These lenses wont crack without some kind of severe shock to them. For how big the Javelot and SR52 lenses are they have all remained very anti static like as despite how big they are not much sticks to them and I use them regularly then again I also sheath them all properly and am not careless with my glass. I am fairly new to Olight still. My first was the SR52 which I consider to be one of the best highest quality high output LED light purchases Ive ever made. Then came the R40A and Javelots. All 4 have done nothing but impress the hell out of me. I consider all 4 to be above the standard that Fenix has set.

OK makes sense to me.
I'm finding the Olight glass much better, less glowing.
They shine up nice, whether it makes you and Harold's skin crawl or not lol.
The Olights take wax like a non hydrophobic glass, very easy, shines like diamond, non abrasive of course.
The Fenix, repel it largely. Look perfectly clean when light is off, but if seen from side at low power, looks like crap as described in OP.
Thanks for feedback everyone.

YW. What on earth are you waxing your lenses with? Even I have never heard of this. If it makes you feel better and hey maybe you do indeed wax your lenses well enough to actually create a very thin and even wax layer that sheens. Sounds like your Fenix AR is pretty oleophobic(anti oil)which is actually a good thing. Would love to see a pic or two of your waxed lenses sometime. Technically the wax is making light transmission more difficult there is no optical grade wax that I have ever heard of but hey to each their own. But yes I have been pretty damn impressed by the Olight lenses they are high quality and very tough wiping off lightly very easily.

Pure caranuba.
It has to harden, cleans and acts as a barrier to moisture but not light. No glass is perfect, wax perfects it IMO without any evidence.
(Think of it as really clear bondo, sand of the thick layers until perfectly smooth) That's my theory.

AR is to reduce reflective glare is it not?
Light from a flashlight by nature of a collimator and focused efforts is still not perfect 90 degree output, so in essence (AR) defines hot spot by nature of electron reduction or glare reduction?
Because the electrons are boiling off en masse throughout head, TIR optics would be most beneficial unless AR is not reducing angular electron pathways?
Electrons are boiling off at around 180 plus degrees, then effort is given to heard them to a focused beam with spill being the by-product of the radical electrons, or the uncaptured light, less then 90 degrees and angular by nature of the freedom they possess.
Maybe too much quantum idk.
It's a wave and electrons.

Edit to add, dedoming aids throwing as more electrons are leaving 90 degrees to surface, but still bleeds to the sides. Reflection reduction would only tighten hot spot, losing free spill light.
If that helps make my thinking clearer.
You bet, I'll set up camera tomorrow and try an capture the M3XS-UT, side shot in moon maybe. Eco on Fenix.

I also collect knives and can get pretty obsessive compulsive over how well I keep them waxed. Thats one thing Ive never heard of anyone waxing their lens before though. AR is there indeed to reduce or eliminate glare and in doing so aids the transmission of light through the lens to nearly 100%. The newer AR coatings I work with in my lab are astonishing. They can also be $80 per lens though I use a brand called Saphire on my eyeglasses its the best AR out there its got it all. Teflon, super hard coat base anti static hydrophobic oleophobic even anti fog. I can only ever see something like Sapphire on a light lens in a high dollar custom build. May want to familiarize yourself with Zeiss AR coatings and Alize by Essilor those are extremely high quality AR. Looking forward to your pics. As a flashaholic nothing is worse than when I buy a light get it and inspect it only to angle the lens in the light and see that the AR gets spotty halfway across the lens and stops now THAT is bad AR(first NC P12 was like that).

Tldr, if the glass glows, there's resistance.
Hence Fenix always having tight corona hot spots on reflector based lights with AR applied.
This is my theory, I welcome to be proven wrong more so , then, it's wrong.
Cheers.

Maybe you're thinking of light and the general concept of energy at too small of a scale or there's a misunderstanding but you are not likely to find discussion of electrons boiling off or resistance at an optical interface. Photons yes, electrons no. The "is it a particle or a wave" discussion become an issue when we are designing systems to count photons but in illumination systems like a flashlight a simple ray trace will suffice. I am not aware of reflectors using an anti-reflective coating. That would seem counter productive. I am aware of filter or selectively reflective coatings for reflectors to reduce UV or IR output.


So then on to some of your points. "If the glass glows it has resistance." Maybe it's terminology here again but in general yes there is a scattering of light going on at the surface. The only time you see light is when it's being bounced/scattered off something. The glass doesn't have resistance so much as it has scattering as does the surface or surface coating. Just because you see backlit surface contamination it does not follow that you will or will not have a specific beam/spot attribute in the far field. The beam characteristics are determined by the optics unless the contamination is so high that the total output is grossly compromised.

Picking through the points in this thread might seem like I'm harassing and that's not my intention at all. Perhaps I should focus (ba-dum-bump) on the AR coating. The point of the coating is to reduce Fresnel loss at the interface between two different refractive indices. The greater the difference between the two indices the greater the Fresnel loss but also the more ability to bend the light to make it go where you want it. You'll have that loss going in and going out but it's not all absorption, some is reflected back into the optic (and often gets bounced around contributing to the huzz around the spot). Between the contribution of stray light and the LED being an extended source instead of a nice theoretical point source, the spot is going to look a little fuzzy even through a multi-lens collimator. I'm always fine with being corrected so if I've been unclear let me know.