Deep UV (254nm) LEDs

DM51

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Bump - for an interesting question. Most of the ones used here in mods etc seem to be longer wavelength, ~400 nm. The ones you mention above seem to be very specialised ones for scientific / medical etc purposes, and probably have to be very precise, hence the high cost.

What do you want to use these for?

And welcome to CPF!
 

Theatre Booth Guy

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Several months ago, I spoke to Curt at Peak LED Solutions looking for something similar. He said that they have and could again, make a UV light with a shorter wavelength. However, at that time, he said the UV led's were even more expensive (I passed and am waiting for better prices).
 

thomaspf

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Thanks for the replies. It looks like no one has a cheaper source for these 254nm LED.'s.

I wanted to build a small flashlight to look at flourescence in minerals and the longer wavelength UV leds do not work for these minerals.

For the time being I will probably go with a standard portable UV light which can be had for about $50.

Cheers

Thomas
 

Lunal_Tic

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Thanks for the replies. It looks like no one has a cheaper source for these 254nm LED.'s.

I wanted to build a small flashlight to look at flourescence in minerals and the longer wavelength UV leds do not work for these minerals.

For the time being I will probably go with a standard portable UV light which can be had for about $50.

Cheers

Thomas

Just curious, what minerals won't fluoresce under a 365nm UV light?

-LT
 

Lunal_Tic

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I thought that glass or plastic stopped the really short UV. How could you make an LED that actually got the UV past the "plastic" package or lens?

-LT
 

thomaspf

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On a recent geology trip my son collected some interesting minerals. I forgot the names but I do recall that some of them contain Strontium which was bright green under these 254nm lamps and they glowed on after turning off the light. We also collected some bright orange and blue stuff.

I have a 360nm UV led and these minerals just don't do anything with that light.

Thanks

Thomas
 

PhotonWrangler

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I thought that glass or plastic stopped the really short UV. How could you make an LED that actually got the UV past the "plastic" package or lens?

-LT

They use quartz instead of regular glass. That's the main reason why shortwave fluorescent lamps cost more than LW bulbs.
 

Lunal_Tic

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A quartz encased LED, that sounds cool. I wonder if a quartz lens would be better than the sapphire that I've got on a 365nm now. I know it blocks a bit of output. I had a hard time finding a high output 365nm, 254nm is going to be tough methinks.

-LT
 

optolite

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The only 254nm LEDs that I know of are the SET ones and as it has been said before they are are too expensive for commercial use. This is because going lower in wavelength is a mix of art and science, there are many factors to consider for manufacturers and it takes more time to develop UV led technology than visible LED technology. Prices do get sort of ridiculous when you go in the UV-B and UV-C range but this is because the technology is just prevailing. I remember the first computer that i bought cost me about 5000$ and well compared to now, in terms of price and performance i would not pay a penny to have one. Expect the same in UV LED technology, its only a matter of time til we have a low wavelength UV LED source that wont cost an arm and a leg.
Cheers
 

optolite

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As for fox Group LEDs theyr typical output is 361 - 362 nm at 20mA, you can get the specific 365nm peak at a higher forward current(wont damage if you want to pulse the LED), or even after keeping the leds on for a couple of minutes( heat shifts the spectrum a little )
 

Linda Tan

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Thanks for the replies. It looks like no one has a cheaper source for these 254nm LED.'s.

I wanted to build a small flashlight to look at flourescence in minerals and the longer wavelength UV leds do not work for these minerals.

For the time being I will probably go with a standard portable UV light which can be had for about $50.

Cheers

Thomas
hello Thomas, since it's a long time of you publish your question.
I think you should already know that now have a alternatives for 254nm led, that is $275nm uvc diode:www.sfleds.com
it's cheap and similar function as 254nm.
 
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