What Are Ultraviolet LED's Good For?

I can say that they make scope CRTs light up real good. Not sure exactly what kind of LEDs you mean, but I've seen violet LEDs used in fake money detectors sold at dollar stores.

You can also get UV CCFLs.

On a sunny day (Fri, 27 Apr 2007 19:59:40 GMT) it happened D from BC wrote in :

Probably not powerful enough, have not tried.

25 minutes on a Germ killer lamp of several Watt is needed?

Na, or takes a long time.

Weak feable ones ? ;-)

SURE

With enough of those.

Yes, this is in fact the only use I have seen, except UV LED as source for white LED with fluorescent layer.

??

There are some physics applications I can think of.

Yes, they're quute good for that.

Kevin

I don't have any fake money, but I understand they have potential for detecting it.

Wandering around the house and garden at night seeing what responds.

Rockhounds use them for identifying some minerals and gemstones

I understand (from a cop mate) that s**en fluoresces under UV light, so it's used by forensic examiners.

Here's one application that may be useful

Barry

Previous (mostly bad) ideas:

*-*-*+priced.cheaply+novelty+zz-zz+further-*-into-the-*-spectrum+funny-*-name *-*-paint+minerals+winter.tan+milliwatts-*-*-*-*-*-*-*-*-*+*-meant-*-*-*-*+zzz+four-page-*-*-+*-stamp-*-*-*+robot+*-*-*-*-wavelength-too-*+art+prop-*-*-*-*+chlorophyll+qq-qq+scorpions

white LED

Oh..about the tonic water See glowing tonic water due to UV exposure on wikipedia

(I can't believe how many times I end up on wiki.....)

When I heard of UV LED's ..I thought cool... However ,I couldn't think of "big bucks" applications...

Phosphor coated backlight? UV glue cure? Invisible ink fun for kids?

I dunno.. D from BC

Really!!! ?? Somebody posted that it's slow.. Did you make a UV led exposure table? D from BC

Cool..I can check the bed for scorpions and also see if it's time to wash the sheets :P D from BC

no - well yes, but you'll ned a few weeks spare - to erase EPROMS, you ideally need UVC which will do it in 10-20 mins

yep

no - UVC does that - it also kills desireable cells - i.e. skin and eye so don't mess with it in the open

if your kiss poster has flourescent inks, they'll shine a treat

long term exposure can result in a tanning of the cornea which is irreversible - but again it'll take weeks of exposure - it won't stimulate the production of melanin in skin cells

yep

tonic glows in UV? didn't know that - maybe... what is fun is you can make a UV torch out of LEDS and go scorpion hunting - the carapace of scorpions lights up like a beacon at night.

also those tubes generate UVC - LEDS all have (those that I have seen) too-low-a-frequency to be useful.

"D from BC" schreef in bericht news: snipped-for-privacy@4ax.com...

No.

Yes. Elector published an UV exposure box for Eurocard size. (24 LEDs, 6 min. exposure time.)

Maybe.

Depends.

Not yet but you can build one. Use enough LEDs. They produce the same light as in face tanners. Can harm your eyes too.

Do you have some?

Don't know.

petrus bitbyter

UVC is really a partial synonym for soft X-rays. UV-EPROMS erase with just about any wavelength under 350 nm (still UVA). Shorter wavelengths and brighter sources are faster. A standard dental X-ray shot (0.6 seconds) will do the job quite nicely as well.

With enough LED's to make a bright source.

UVC does the job nicely, but no LEDs emit that short wavelength yet. Ultraviolet light in the germicidal wavelengths ? 185-254 nanometers. found at:

Again source power is an issue versus gas discharge lamps.

Possibly, if you could afford hundreds to thousands of the very shortest wavelengths available (about 325 nm last i looked, and very expensive).

Sources at 350 nm are short enough wavelength to cause tonic water to fluoresce. The fluorescence peak seems to be around 450 nm.

Via google:

Question

What is the wavelength of UVa, UVb, and UVc light measured in nanometers, and frequency (in Hz)? Asked by: Richard M. Arnold, B.S.

Answer

According to multiple sources (NASA, FDA, and others) here are the wavelengths of the UVA, UVB and UVC regions:

UVA 400 nm - 320 nm UVB 320 nm - 290 nm UVC 290 nm - 100 nm Found at:

--
 JosephKK
 Gegen dummheit kampfen die Gotter Selbst, vergebens.  
  --Schiller

C. That is the money maker. Get your act together and go for it.

--
 JosephKK
 Gegen dummheit kampfen die Gotter Selbst, vergebens.  
  --Schiller

No

Probably but you need too many to be useful

No

Yes

No

Yes

Yes

>

Writing messages on glow-in-the dark emergency signs.

[snip]

There might be just enough time to get it on Walmart store shelves before Christmas. :) All I have to do is mod some led flashlights. D from BC

It's never that easy :( Well..back to work on my other invention: The talking vacuum: Rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr "Bag full!" What? " Bag full!" What? "Bag full!" D from BC

I found a UV LED built into an invisible-ink pen (including three button cells, IIRC) at the dollar store.

Best regards, Spehro Pefhany

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