First thing I did was search for a good LED pen / flashlight.
I looked for one with a push button on the side so that activating the light while "drawing" would be easy.
I found this one on Ebay and bonus its rechargeable via USB!:
It is from "Genaldi" more info here:
(you can also buy it on their site for $10)
http://www.genaldi.com/usbrechargeablelaserled.htmlThe dimension is about 3/4" wide X 1/4" High X 2.5" long.
Here is what I did to modify it for an IR LED
1)I unscrewed the mini screw holding the battery cover and removed the battery.
2)Using a small flathead screwdriver I was able to separate the 2 halves (they are glued / snapped together.
3) When separating the 2 halves be careful of the wire from the battery connector to the main board. I didn't see it and had to re solder the wire to the mainboard after.
4) Remove the mainboard (slides off guides easily.
5) Heat the solder (using your trusty solder gun)on the 2 connectors for the LED and remove it. Take not of which side is the "fat " end so that when you put on the IR LED that it matches.
6) Cut your IR LED to the same length and then re heat the solder on the mainboard and attach the IR LED.
7) Re insert the Mainboard into the case and close. insert battery and re screw the cover closed. To test that everything is still working fire up the laser.
Your done!
I am going to test the PEN soon but this was very easy to do.
