UV LED Spotlight

So based on my last LED spotlight, I decided to make a LED Blacklight spotlight. I went over to RadioShack and picked up some ultrabright UV LEDs for $1.69 a package (each package contains 2 LEDs)

I already had some 330 ohm resistors lying around and used the LED array calculator over here to make sue I had the right ones to drive the LEDs with a 9v battery.

I soldered up the resistors to the LEDs and tested them with the 9v battery

Then I soldered up some wires and used some heat shrink tubing to make sure nothing shorted out. Then I soldered all of the wires up to the battery connector and attached the battery to make sure everything was working.

For the housing I uses some recycled film cans (thanks again Ghostess D!). I just cut the bottoms off of 2 of the 3 cans and stacked them to make a large tube then used hot glue to hold them in place (I will probably use pvc for the final housing, but I am making a proof of concept here). I  then drilled 4 holes in one of the lids and poked the LEDs through the holes and secured with more hot glue.

I was amazed at how bright these little LEDs were. 4 was more than enough to light a tombstone with glow in the dark paint.

Below is a shot outside, but it didn’t turn out so well. I will try to get a better shot another night.