Mastodawn

on today's installment of parts that terrify me:

I don't actually know much about this LED, but it's certainly a very strong, possibly ultra low wavelength UV led. The incredibly clear cover-glass and the fact that the dies are water-cooled give off an eerie vibe.

I’m actually scared of figuring out the output power and wavelength by hooking it up to a lab supply. Anyone who knows what specs this could have? What part no it could be?

another glamour shot, I should do a focus stack! Also this device is both tiny and way too large at the same time, it’s also quite heavy!

so, that LED is likely a 405nm 9W led. Thats not too terrifying actually, not even really UV light! We can do better, how about this device

It has two 6W light sources, one emitting at 366nm, that’s certainly UV! UV-A to be precise.

The other tube however has its peak at 254nm, UV-C light. Now, that’s scary!

or even better, how about this bare Deuterium arc lamp. Its spectrum starts at 112nm and is continuous from 180nm. Thats almost covers the whole UV region, bordering into the Extreme UV/EUV region (<121nm).

This thing is really really scary and I will likely never turn it on. Looking down it’s "eye" (second photo) is fun though…

Sarah [7252]Feb 26

@janamarie how to Hautkrebs fast

srslypascal Mar 3

@Exilsarahl @janamarie

Verbotene Ultrakurzwelle

Andrew Zonenberg Feb 26

@janamarie I want a deuterium lamp! my spectrometer has a halogen light source on it currently but that tops out around 350-400 nm so while the detector is sensitive down to 200 I can't actually do useful transmission measurements that low

Andrew Zonenberg Feb 26

@janamarie the vendor had a deuterium option available for it but it was $$$$ and i had no immediate need so i didn't buy it

Andrew Zonenberg Feb 26

@janamarie Given how much stray light leaks out from around the halogen lamp housing, I'd definitely be wearing my good eye pro while running it lol

@azonenberg oh, you can 100% have it! I would have thrown it out/trashed it some time anyways… it has an unknown runtime though

Andrew Zonenberg Feb 26

@janamarie If it's a bare lamp and not fiber coupled it's not useful to me and I don't have the time or skill to do the optical design to make it so.

Just drooling about the idea of eventually having one

@azonenberg damnit, almost got rid of it :p

std_logic_vector Feb 26

@janamarie Instead of throwing it in the trash, may I have the D2 lamp? I have an UV spectrophotometer that is missing its lamp and the holder on yours looks like it might fit...

@stdlogicvector sure! (dw though, I wasn't going throw it out anytime soon, but I literally have zero use for it, so I would love for it to find some use!!)

@janamarie In the chemistry lab we had an UV lamp with two different wavelength. One must have been UV-A, the other UV-B, something like 370 and 270(?), but I don't longer remember. Of course it was setup so you could not look at the light source. But using the later one was really uncomfortable from the reflections alone.

Trammell Hudson Feb 26

@janamarie we borrowed a UV lamp sort of like that for curing a countertop and it was terrifying

@th @janamarie <europe overcast weather joke goes here>

(...he posts from sunny ZA)

fundamental Feb 26

Richard "mtfnpy" Harman (he/him)Feb 25

@janamarie imagine getting a laser cut stencil so you can give people pretty sun(burn|tan)^Wcancer

Ross of Ottawa Feb 25

@janamarie Those are some long-reach wire bonds.

I've had the pleasure of doing manual wire bonding years ago - I can't imagine doing those without careful planning to not get tangles and shorts. Fun machines to use, though frustrating to get dialled in.

Andrew Zonenberg Feb 25

@janamarie If you can get it to me, I could run it on my spectrometer at low power (just enough to get an emission line) to find the center wavelength, assuming it's >200 nm. I have a UV-VIS-NIR spectrometer and laser-rated goggles that are OD 5+ from 190 to 400 nm so combining them with skin protection I'm not worried about whatever UV it might generate.

But I'm based in the US and the closest I am likely to be to you in the near future is Bochum in a couple weeks which is still the wrong end of the country, so I would assume you can find a spectrometer closer to you than that.

I don't think there is a good way to figure out the max safe power level without any part number or ratings though, since the upper limit is usually thermal and you don't have any easy way to measure the die temperature (or even know what the max temp it can tolerate *is*). You'd probably be best off slowly cranking it up while looking for thermally induced wavelength shifts and stopping when it moves "too much" or power starts to decrease, then de-rating by a bit from that cliff

@azonenberg ooh, thank you for your offer!! I will think about it, but you’re probably right that the logistics would be complicated. Bochum is not too far away, but you surely will not have the spectrometer on hand then? Shipping it back would be a huge pain.

Re power level: you’re completely right, it’s not really possible to get all characteristics without destroying it. I would have done something similar to what you proposed. Crank the power up, plot the curve, monitor the temperatures (case and water flow), figure out where the curve flattens out and use that as set-point estimation. That wouldn’t really give me a maximum power, but a somewhat safe operating point. A shame I don’t have a part number

Thanks for the explanations!

Andrew Zonenberg Feb 25

@janamarie It's a little USB powered spectrometer, if you're able to give me some level of commitment that it will get used I can probably install the drivers on my laptop and shove it in my suitcase.

Andrew Zonenberg Feb 25

@janamarie (you'd have to provide some way to power it as I won't be able to bring a lab supply with me, too big/heavy)

Andrew Zonenberg Feb 25

@janamarie It would be cool to meet another cool German nerd either way... right now possible options are evening of Saturday March 21, any time Sunday the 22nd, and Monday the 23rd before about lunchtime.

I have several other possible meetups I'm trying to pack into Sunday (none actually scheduled yet) but don't have anything lined up for Sat/Mon right now

Peter Sommerlad Feb 25

@azonenberg @janamarie
I guess you'll see me at embo++ then?

Andrew Zonenberg Feb 25

@PeterSommerlad @janamarie wrong conference I'm speaking at https://harris2026.mpi-sp.org/

But if you're in the area and want to say hi, by all means

HARRIS 2026

Hardware Reverse Engineering Workshop (HARRIS 2026)

Peter Sommerlad Feb 25

@azonenberg @janamarie

too much of a software guy to be aware of this event. unfortunately i am booked all Saturday and returning on Sunday.

Andrew Zonenberg Feb 25

@PeterSommerlad @janamarie then we won't overlap anyway my flight lands DUS around 5pm Saturday so by the time i get to bochum it'll be late

@azonenberg ooh, I will think about it and come back to you!! Thanks

Cat 🐈🥗 (D.Burch)

@janamarie @bimmer Wonder what it tastes like?

@catsalad @janamarie my money's on 9V battery but milder

RootWyrm 🇺🇦

@janamarie this looks like it may just be a very high power white module, but may also be a UV curing module. Either way, this is definitely in the 100W+ class and you do NOT want to look into it either way. Or operate it without water (distilled only) for even a MINUTE.

@janamarie And to be turned on when on the proper heatsink and not in line with your sight - being it in the visible range or not.

@janamarie any idea what the small separate die in the bottom right is?

@jasper not really, could be a TVS diode

@janamarie @jasper I guess it is rather something to measure temperature

@josyb @jasper probably not, it is in parallel with the diodes, no extra pins

Is it cold to the touch?

@janamarie @claudius spicy cancer lamp