Just got an ultraviolet LED in a 10 mm epoxy package that’s water-clear in visible light and slightly fluorescent in its own UV:
The epoxy usually has some fluorescence, but this seems more dramatic than usual. In any event, the die’s wide beam angle shows clearly; the beam along the axis out in front is actually pretty tight.
It’s sitting on the back of a white ceramic tile and the colors came out surprisingly close to real life.
Adding this to an Arduino would follow the same logic as, say, the pager motor: power the LED + resistor + MOSFET from a +5 V external regulator that won’t heat the Arduino board, then define an unused bit in the shift register as, say UV_LED.
It runs at 20 mA and drops around 3.3 V.
The Smell of Molten Projects in the Morning 
Comments
6 responses to “Large UV LED Self-Fluorescence”
Just wondering, did you get any other specs on the part?
That link (while it lasts) has all the information we’ll ever get: it’s a surplus find. [grin]
Paper fluoresceses quite brightly, so there’s some actual UV amid that pretty purple glow. More than that, I cannot say…
CREE makes a purple/UV led, Could be their fallout.
And now I’m an awful lot poorer, since I can’t buy anything from Electronics Goldmine without also buying ten times as much other crap. Curse you! :)
Wait for the regular sales and you can buy 50 times more crap… [grin]
[…] one of these from an Arduino would be just like the UV LED: redefine a bit in the shift register bitfield and drive the laser with a MOSFET […]