Datasheet

The paper acts like a rear-projection screen. In signal processing terms, it's also acting like
a low-pass filter (http://adafru.it/cWb) or blur. The hard edges of each LED are filtered out,
and the result looks much more like what appears on-screen.
Next, let's take the same piece of paper, crumple it up, then flatten it. This adds a lot of
interesting texture, and you can start to see how the moving light interacts with a complex
3D object.
Objects that cause interesting shadows and reflections are especially fun. If you have glass
beads, marbles, or other small non-conductive objects, you can try piling them directly on
top of the NeoMatrix. This is what it looks like with a pile of opaque white glass marbles:
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