JanaFeb 25

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?

Show threadJanaFeb 25
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!
Show threadAndrew Zonenberg

@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

Feb 25 at 3:14pmWeb
Show threadJanaFeb 25

@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!

Show threadAndrew ZonenbergFeb 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.
Show threadAndrew ZonenbergFeb 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)
Show threadAndrew ZonenbergFeb 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

Show threadPeter SommerladFeb 25
@azonenberg @janamarie
I guess you'll see me at embo++ then?
Show threadAndrew ZonenbergFeb 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)
Show threadPeter SommerladFeb 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.

Show threadAndrew ZonenbergFeb 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
Show threadJanaFeb 25
@azonenberg ooh, I will think about it and come back to you!! Thanks