Looking for cheap small UV light..

Planterz

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The real question (besides quality) is the wavelength the LED. A violet 405-410nm wavelength light will fluoresce most things that show up in UV. I carry a violet Photon keychain light (405nm) and it fluoresces things better than the UV Photon simply because it's brighter (at least it looks that way). The UV Photon is 370nm, which is mostly invisible to the naked eye and does produce very accurate UV color rendition. What I mean is, unlike the violet Photon, the UV doesn't tint things purple, "tainting" them. Like when I shine the tritium vials on my Luminox, they show up the correct color under UV, but under the violet the color isn't quite the true color.

My brighter UV light is a Jil which uses the Cree 7090 UV LED, which is far brighter than the 5mm LEDs in those cluster lights. It's 395nm so it's less purple than true violet, but it's still a very visible purple.

The problem regarding that UV light you have in your link is that we have no idea what wavelength the LEDs are. It also matters what you're intending to fluoresce. If it's just highlighters, UV ink (for handstamps or whatnot), or symbols on ID cards and such, most any UV or even violet light will suffice. Heck, even blue LEDs can fluoresce some things like highlighters. If it's to detect cat **** or scorpions, or other more specialized uses, there's also specific wavelengths that function best for each circumstance.
 

ericg533

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The lighthound UV light is 395-400nm. I have one. It's fun, but outputs mostly visible light.
 

fire-stick

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Mainly just looking for something to detect human/animal "fluids".

If the UV light doesn't say what the wavelength is, is it pretty much guesswork.
 

xenopus

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Hi:

380nm is a good wavelength to detect bodily fluids. If, however, your forensic sample is on bedsheets which have been washed with brightners in the detergent, then the whole sheet will fluoresce. The answer in this case is to excite with blue at 465-470nm, for example, and use orange barrier glasses.

Cheers,
Piers
 

fire-stick

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xenopus said:
Hi:

380nm is a good wavelength to detect bodily fluids. If, however, your forensic sample is on bedsheets which have been washed with brightners in the detergent, then the whole sheet will fluoresce. The answer in this case is to excite with blue at 465-470nm, for example, and use orange barrier glasses.

Cheers,
Piers

WOW Thanks.. Straight forward answer!! Nice website too.. I know where I'll be buying my UV light from......
 

PeterScowcroft

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Oct 1, 2006
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I am also looking for a UV light with a slighty different use.

I do have to ask first, why do you want to highlight bodily fluids?


Certain types of limestone/calcite are supposed to flouresce red in UV light.

This makes an idea for a very interesting cave light.

Does anyone know what frequency excites limestone/calcite and which UV leds use it?

I would also prefer NO visable light to be sent out of the torch.

If my plan works my flashlight should make the cave walls glow but I shouldn't be able to see anything else.


Anyone have any good suggestions?

I bought that light off ebay, quite purple, seems to work quite well and good build quality.

Just checking for body fluids brb.

Nope according to this light my sheets are clean as clean can be (not very likely)
 
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Trashman

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No visible light? I think you're looking for something in the 352-360nm range. The ones on ebay that state 380-385nm in the title don't put out too much visible light, either, but definitely more than a 360nm.
 

PeterScowcroft

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The critical thing is the ability to fluoresce limestone!

If I still worked in a lab this info would be so easy to get, I can't seem to find it anywhere!
 

Trashman

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AndyTiedye

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Oct 28, 2006
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Santa Cruz Mountains
I just stuck a UV LED into a regular MiniMag and drilled out the reflector to fit.
It seems to be the right voltage to direct-drive it.
 
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