# UV LED Options?



## tomcat017 (Sep 10, 2013)

Hello all,

Wondering what the best options are for UV LEDs currently on the (reasonably-obtainable) market. Ideally, I'd like to eventually obtain/build a light in anything from a 2-primary to 3D Mag form factor. What I'm looking for are (1) negligible visible light output and (2) coverage in the 350 nm range. The wider the UV spectrum, the better (though not looking for any UVC or germicidal). I have an arc AAA UV, but it's way underpowered for what I need. I built a UV HID, but the glass window lasted all of 30 seconds (see here tragedy http://www.candlepowerforums.com/vb...pt-at-UV-HID-Mag-failed&p=4277502#post4277502). The output was perfect (tons of light, good spectrum coverage). Is there anything comparable in LEDs? If I were able to track someone down willing to build a custom light?


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## rayman (Sep 11, 2013)

I'm looking too for an UV light for quite a while. I think getting a quality emitter is the problem over here. There were some UV Cree XR-E around but they were pretty had to get.

I found a budget UV light by accident which seems to have a UV Cree XP-? in it. Normally I'm not into budget lights where you don't know what company they are coming from with most fake flashlight-manufacturer "....fire" names. You can find the light on Fasttech and here is a small review with a clear picture of the led. Even on the shops website you can clearly see thats some sort of Cree XP-?. I just ordered one and can write a little review on here when I get it. I think buying the light is even worth if you only want the emitter as I don't see any cheap source of quality UV LEDs.

Btw: I'm sorry for your failed project . I'm really into Maglite mods and this seem like a real nice mod.

rayman


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## TweakMDS (Sep 11, 2013)

I use a Nichia NCSU033B led that datiLED modded for me to go into a McGizmo AMC Mule (he made the whole light engine can actually, so it just screws in). 

Afaik they are special order, but if you're interested you can drop him a line. Perhaps he will do another run of Nichia LEDs - if enough people are interested.

Fantastic little light, but it's horrifying to actually use in the kitchen, because you'll realize how much filth there actually is. The risky thing with this light is that it's extremely bright, but almost completely outside the visible spectrum. Goggles are an absolute MUST.

My initial purpose was to use it for flower and insect photography, but so far I've only played with it (a LOT).


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## evilc66 (Sep 11, 2013)

LEDEngin has a few options for UV LEDs in the 365nm range. They aren't cheap. If you want to go into lower wavelengths, then take a look at Roithner Laser. Lots of options, but again, silly expensive.


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## tomcat017 (Sep 11, 2013)

Thanks guys. Tweak, I'll look into that, it sounds perfect. Do you know approximately what it's putting out in terms of power and wavelength range? If it's primarily UVA, are the goggles really required? Is it just the intensity? B/c that part of the spectrum shouldn't be too damaging, yea?


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## TweakMDS (Sep 11, 2013)

tomcat017 said:


> Thanks guys. Tweak, I'll look into that, it sounds perfect. Do you know approximately what it's putting out in terms of power and wavelength range? If it's primarily UVA, are the goggles really required? Is it just the intensity? B/c that part of the spectrum shouldn't be too damaging, yea?



Not too sure on the details, I think mine is a 3-stage GDuP light engine driven at either 1 or 1.4A on max, but not 100%sure (datasheet says 1000mA max, so probably that). It's a pretty narrow 365nm band. Afaik, that particular led is actually the narrowest of the common UV leds (meaning it doesn't emit much light below of above the 365nm wavelength band).

Here's the datasheet, check out page 10: http://www.nichia.co.jp/specification/products/led/NCSU033B-E.pdf

Regarding eye protection, the problem with using UV light in a dim room, is that your pupils will be wide open. Since bright UV light will not trigger your irises to close down, you're exposing your eyes to a buttload of potentially damaging light, which will eventually deteriorate your eyesight (cloud up).
Besides, if you plan to use it for any sort of fluorescence, amber UV glasses are the way to go anyway, as they'll actually enhance the fluorescent colors while cutting down the little amount of visible light that the LED emits.


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## desertdog256 (Sep 11, 2013)

Google "32 UV LED" and you'll find an LED array that works in the Maglite. I have one in my 3D and it is very bright for scorpion hunting in the desert. Less than $30USD.


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## 8steve88 (Sep 12, 2013)

If you have a p60 host then try this 365nm drop-in, I've found it to be much better than the other ready made options that I've tried.
I'm running it at 18v - 6x3v 123A Lithium primary cells in a Solarforce L2P with 2 extension tubes and AR glass lens.
Solarforce $25.50 + $2 Shipping =$27.50
Kaidomain drop-in $15.81
Kaidomain AR glass lens $3.03
FastTech, 3x2pack CR123A 3x$3.23 =$8.91 ($0.78 discount for 3 packs)
Total = $56.15

OR

I've heard these are good, Tank007 UV also available at your favourite flashlight store online.


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## TEEJ (Dec 5, 2013)

I just got a Xenopus Electronix 365 nm UV light, and it has the Nichia NCSU033B LED mentioned above, it puts out about 450 mW at the 365 nm peak, in this application.

It uses an optic instead of a reflector, and can run on two CR or RCR123's, or an 18650. (Its output is regulated)

Its a BEAST as far as output, at least compared to my other UV lights, even the 3D Mag conversion UV scorpion hunter can't out throw it. The 365 nm part is very potent, it has almost no visible light, but, fluoresces things like crazy. 

I like it.


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## joeray (Dec 16, 2013)

Just a quick and maybe off topic question:

For UV LED lights, at which wavelength does one need to worry about eye protection so one does not damage they eye? I believe it's 365 and shorter wavelengths, is that correct?

thanks in advance.


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## TEEJ (Dec 16, 2013)

joeray said:


> Just a quick and maybe off topic question:
> 
> For UV LED lights, at which wavelength does one need to worry about eye protection so one does not damage they eye? I believe it's 365 and shorter wavelengths, is that correct?
> 
> thanks in advance.



All of them actually. It feels like you have sand in your eye, etc, with even a minor exposure with 390 nm for example.


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## jspeybro (Dec 28, 2013)

What's your application? 
350nm is already a short wavelength for LEDs. down to 365nm, they are reasonably priced, but going any shorter, drives the price up in the hundreds of dollars for just a few mW of power. 
Going below 350nm will most likely not work well, since you'll need special materials that are transparant to these wavelength. Simple PC, PMMA or glass will simply block all of your light.
Also, you ask for LEDs, and want a broad spectrum. These 2 things don't go together...

As mentionned, LedEngin has a good range of high power 365nm leds. They glow purple, but do produce a lot of light. Don't look straight into these LEDs or you may damage your eyes. You can already damage your eyes with blue light, so don't look into UV lights wether it's an LED, HID or fluorescent lamp! 

*Regarding safety:*
It's not the intensity but a photochemical effect in your eye that is dangerous. In laser safety circles, people talk about the blue-light hazard:
http://en.wikipedia.org/wiki/Blue-light_hazard#Blue-light_hazard
Wavelengths shorter than 400nm, cause damage to tissue, and since your eyes are the most light sensitive tissue you have (and you only have 2 eyes, ever), don't just mess around with it!
Don't just have fun and shine it in peoples eyes too.
Fluorescent lamps are broad sources with low surface intensity, but LEDs can have high intensities on a small surface and can be dangerous!


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## PhotonWrangler (Dec 28, 2013)

As jspeybro mentioned, LEDs are pretty monochromatic by nature so you won't get much of a spread in terms of wavelengths. You specifically mentioned 350nm; are you using it to look for a specific substance that fluoresces at that wavelength, or are you just looking to get as far away from the visible spectrum as practical? I have a flashlight based on the Nichia NCSU033B and it does ok in terms of good fluorescence with low visible light output, although it has a minor annoyance where I can see the die pattern in the projected beam, making for a somewhat mottled beam pattern. Anyway I think the Nichia currently hits the sweet spot in terms of price/performance ratio.


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## TEEJ (Dec 28, 2013)

PhotonWrangler said:


> As jspeybro mentioned, LEDs are pretty monochromatic by nature so you won't get much of a spread in terms of wavelengths. You specifically mentioned 350nm; are you using it to look for a specific substance that fluoresces at that wavelength, or are you just looking to get as far away from the visible spectrum as practical? I have a flashlight based on the Nichia NCSU033B and it does ok in terms of good fluorescence with low visible light output, although it has a minor annoyance where I can see the die pattern in the projected beam, making for a somewhat mottled beam pattern. Anyway I think the Nichia currently hits the sweet spot in terms of price/performance ratio.



I have the same LED, and concur


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## tomcat017 (Dec 28, 2013)

Thanks, all.

I was both looking to go farther from the visible for minimal light output, and to fluoresce substances with a peak response at ~350nm. As you've all pointed out, I recognize that spectral width is limited with LED. I've been using nailbender's LEDgine P60 dropins and have been extremely impressed, especially for the price. The UV HID project has given me the best results so far, but it's silly expensive, and I don't want to break another glass window within 20 seconds (costly mistake).

I'd like to try out the Nichia NCSU033B that you guys are talking about - which lights are you using that have this emitter? Thanks!


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## TEEJ (Dec 28, 2013)

See post #9 for what light has the LED.




If the stuff glows best with 350 nm, then you are going to need a different LED though for best performance...one that goes down that far.


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## tomcat017 (Dec 28, 2013)

TEEJ - any particular product here you can personally confirm works great for you?

http://www.xenopuselectronix.com/xeled/index.html


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## TEEJ (Dec 28, 2013)

tomcat017 said:


> TEEJ - any particular product here you can personally confirm works great for you?
> 
> http://www.xenopuselectronix.com/xeled/index.html



*XeLED-Ni1UV-R3-365-SS-K


*


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## tomcat017 (Dec 28, 2013)

Thanks TEEJ! Have you had a chance to compare it to an LEDgine Cree UV P60, like the one's nailbender offers? Curious how extreme the difference is.


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## TEEJ (Dec 28, 2013)

tomcat017 said:


> Thanks TEEJ! Have you had a chance to compare it to an LEDgine Cree UV P60, like the one's nailbender offers? Curious how extreme the difference is.



No I haven't.

If someone sends me one, I'll pop it into a host and try it out though.


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## tomcat017 (Dec 29, 2013)

TEEJ said:


> No I haven't.
> 
> If someone sends me one, I'll pop it into a host and try it out though.



Using mine for class right now, but as soon as we're done with ALS, I'd be happy to ship one your way for comparison if you take a few beamshots


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## TEEJ (Dec 29, 2013)

tomcat017 said:


> Using mine for class right now, but as soon as we're done with ALS, I'd be happy to ship one your way for comparison if you take a few beamshots



No problem.

Let me know before you ship it though.


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## Bronco (Jan 5, 2014)

Not sure if this is helpful or not, but when talking about broader spectrum UV lights, I immediately think of the Streamlight Night Com. I have one of these and it's a pretty solid little light. It has a 2xCR123 form factor and isn't terribly expensive. There's a central white C4 LED that operates independently from an outer ring of six smaller UV LEDs which all illuminate at the same time. Three of the UV LEDs are 365nm and three are 390nm. I realize this puts the spectrum in a higher range than the wavelengths you're seeking, but the UI and driver set-up is so convenient that it might be worth exploring a mod in which a range of UV LEDs more to your liking could be swapped out for the stock ones. 







http://www.batteryjunction.com/streamlight-51046.html?gclid=CMyjwdLW57sCFQuUfgodb3gANQ


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## tomcat017 (Jan 7, 2014)

Thanks Bronco!


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## alpg88 (Jan 7, 2014)

just don't use polycarbonate lens with uv led.


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## davesc (Jan 7, 2014)

alpg88 said:


> just don't use polycarbonate lens with uv led.



Just curious...Why?


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## alpg88 (Jan 7, 2014)

it blocks uv. you want either pete, acrylic, or glass. also, i would check if AR coating wont block uv as well.


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## davesc (Jan 8, 2014)

Thank you...I did not know that.


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