Hey guys,
Any of you know a good source for UV LED's? Somewhere in the 250-270 nm range would be excellent.
Hey guys,
Any of you know a good source for UV LED's? Somewhere in the 250-270 nm range would be excellent.
I think Rudy might have some
Google Fu has few answers, but that wavelength is not in the LED (380 nm) sweet spot,
and therefore would be expensive.
Mercury vapor lights are considered the best solution.
Those shorter wavelengths are more dangerous biologically.
Useful for sterilization, so maybe industrial medical? Maybe industrial epoxy curing?
Last edited by WØTKX; 04-13-2011 at 09:12 AM.
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
Here ya go...make your own!
http://lib.semi.ac.cn:8080/tsh/dzzy/.../110-14685.pdf
OK...so I'm the Island smartazzficktard de jour.
oh well good luck!
Just had to do it.
Take Care
rot
"In the field of opportunity, it's plowing time again."
N.Young
Trying to understand that document made my head hurt...Originally Posted by rot
All the world’s a stage, but obviously the play is unrehearsed and everybody is ad-libbing his lines. Maybe that’s why it’s hard to tell if we’re living in a tragedy or a farce.
LOL nice. I have access to all sorts of things like deuterium lamps and such, which I could use but I'm trying to keep it simple. I want to build a calibration standard for UV spectrometry. What we've been doing until now is running caffeine in Methanol, which produces a big peak at 208 nm and a smaller one at 272 nm. It's a slow, painful way of calibrating. I have an old diffraction grating I want to use, wherein I will shine a wideband (>10 nm) UV LED light source at it, and the output will be a slit in the chamber where the LED and grating will be fixed, at the correct angle for a known wavelength. This will give me a really accurate and stable narrowband UV light source, which I can then put in an RID or similar LC analyzer to calibrate the wavelength setting.
They sell such things, but they're thousands of dollars and I pretty much have all the parts to build one myself, and known working equipment to calibrate it against, so per usual I wanna roll my own....
The skinny zinc oxide wires are interesting. Wonder if you could build that?
By Tesla's Ghost! I thought you were making a death-ray.
Avatar Material.
"Where would we be without the agitators of the world to attach the electrodes
of knowledge to the nipples of ignorance?" ~ Professor "Dick" Soloman
I don't understand. are you calibrating a spectrophotometer for analytical use?
the reason i ask is the RID and LC mean Refractive Index detector and Liquid Chromatography to me...not sure if this is what you meant..I do this all the time.
I do not know why this is slow and painful...unless you are doing something completly different.
You can get certified films to do this and most of what you pay for is the cert.
If you want to use Caffieine/Meoh which is fine to make sure of the methanol purity...It will have a uv cutoff (usually 190nm).
Just wondering.
rot
ps i just checked most methanol has a uv cutoff of 205...a bit to close for 208 work,
Last edited by rot; 04-13-2011 at 11:21 AM.
"In the field of opportunity, it's plowing time again."
N.Young
Yep, that's exactly what I'm talking about. And yes, it's painful because we seem to get a lot of false peaks. We look for the peak at 272. The 208 peak is oxygen, as I'm sure you know way better than I. I'm just learning this stuff.
Well I'm a bit confused again..an RID has nothing to do with UV. RI is a light bending property of whatever you flowing through the cell. UV is a different detector type all together. Now for your false peaks if you are using an RI, then it is your column is not separating what you are looking for? Can you give me analyte, column, eluant, and detector briefs...I'll be glad to help if I can.
rot
"In the field of opportunity, it's plowing time again."
N.Young
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