We tried many different types of pens for our Wiimote Whiteboard.
There are a lot of different kinds of light rays. For example, the gamma rays and Infrared radiation rays. But they have different wavelengths like the gamma rays have a squeezed and short wavelength but Infrared radiation rays are spread out and long. We can't see any of these rays but we can see visible light rays.Infrared Radiation are given off by warm objects. We purchased infrared light bulbs that gave off wavelengths visible to the wiimotes but not visible to the human eye.The Infrared light we can see in a camera but not in our eyes. Just to see if Our IR light pen was working we shined it in a camera.

1. These are some of the lights that didn't work. _fjkdsl;alskdjfds;lf2. This is how you make an infrared light out of an LED keychain light.