# AR Coated lens changes light color



## Mr. Nobody (Mar 13, 2015)

I just got in a AR coated lens from Sweden and it changes the XM-L2 cool white color to a funky green/yellow almost NEUTRAL. :sick2: I don't like it! it looks exactly the same as the OE lens but def messes with output


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## smokinbasser (Mar 13, 2015)

There is a AR coating and it might be if it's installed backwards it permits some lousy light through. I'm just guessing as to the results. I just hold the filter next to a light source and see which side doesn't reflect as well if at all.


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## Mr. Nobody (Mar 16, 2015)




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## Anders Hoveland (Mar 27, 2015)

Mr. Nobody said:


> I just got in a AR coated lens from Sweden and it changes the XM-L2 cool white color to a funky green/yellow almost NEUTRAL. :sick2: I don't like it!


If the AR coating is not thick enough, or was not applied properly, this can be a problem. In this case the coating would be more effective at not reflecting longer wavelengths than the shorter ones. The blue wavelengths in LED light tend to be shorter than the blue wavelengths from incandescent light, color temperature being held equal. My guess is they tested those anti-reflective lenses with incandescent light, not fully anticipating aesthetic problems that would result when the light being focused was from an LED.


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## SemiMan (Apr 1, 2015)

The one comparison picture you posted are from completely different flashlights so it is hard to make any comment.

Frankly, it does not make any sense as the AR coating materials used in the visible range are pretty much transparent in the visible range, even at the blue of the LED.

As AH points out, could be a flawed AR coating, and/or you got one that is not actually a visible IR coating. When you look through the lens, does it have a bit of a tint -- likely towards red/brown? There are some AR coatings that are really intended for near IR, but they are clear through most of the visible spectrum except into the blue. That would do what you are seeing.


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## markr6 (Jul 1, 2015)

I started to wonder about this on my Zebralight SC600w II L2. The tint on it is WAY better than any other Zebralight I've had and actually one of the best tints I've had in general.

The coating on this is very noticeable, much more than any other light I own. I wonder if it's actually making the tint better? It's neutral, but almost cool. Very nice!

I don't even remember what that one is on the back right, D25LC2 maybe, which I sold.


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