Ultraviolet Light Pen

Step 5 What can I use this for?

Now, you may be thinking this is a good waste of money, but you would be wrong. There are plenty of things you can do with this.

• write with a hilighter and shine the light on it, it will glow bright green.
• take all of the ink out of the hilighter and shine the light at the bottle it will light up.
• use it to glarge glow in the dark Nerf Fierfly darts.
• use it in pair with an ultraviolet reaveal invisible ink pen to write secret mesages.
• use it in place of a blacklight.
• at night go into a room with all the lights off and shine the pen around, se what glows you'd be supprised at what things look like.
• go to the dollar store and buy some clear uncented hair gell, put one hilighter's worth of ink in it to make some cool glowing gel
• shine it at U.S currency to see if it is real, if it is real you should see the security thread, ( this dosn't work with $1 bills)

there are proably hundreds of uses for this that I'm not aware of, if you know of any PM me, remember to rate! (and comments are cool too!) :D
P.S. the joule thief on my pen makes a very high pitched noise, does anyone know why, or how to stop it; its driving me nuts!
EDIT: As Uldics told me the high pitched noise is caused because the windings arent tight enough, and can be fixed by rewinding or covering the windings in epoxy. Thanks Uldics! :)

Comments

[setsunafseiei]

A good practical use would be to detect fake money bill. It is really convenient because it's portable (or should be anyway). The moment the dollar bill doesn't feel right at your fingertips, use your pen, show it to the cashier, and ask for another bill. And if you're a good citizen, after getting a real one, take that fake one to a bank nearby.

[shizumadrive]

If you collect or sell vasaline glass it will glow under this light. And if you wander in the desert at night scorpions glow when show with UV.

I have some "doctor who sonic screwdriver" with uv light and it doesnt seem to use much more than a uv light and batteries.

[junits15]

Great idea I'll add that in the instructable :)

[whiskey]

How about getting a scented candle (with a glass container), give it to mom/spouse/girlfriend but ask them for the container later, fill it with hair gel + highlighter ink.  Put the UV LED on the gel and you get a cool lamp :D

Nice job btw, and keep us posted on how did they do that silicon gun sculpture XD

[codex653]

the highpitched noise is the coil resonating and yeah it does drive you nuts!! :)