[LibWhacker]

. . . and emit it at the same trajectory . . .

This seems like it would be the hard part. How do you get it (the light) to come out on the same trajectory? Otherwise, it's just a fiber optic suit. The Discovery Channel aired a program that talked about this research a while back.

[AmericanAge]

Exactly. The angles won't be the same. Not to mention the massive cost issue involved in having even just a thousand "cameras". At best, we're talking about a slight improvement on standard urban camo.

I've toyed around with the concept of using downconversion to the microwave spectrum for stimulus of light emission on the other side so that individual sensors and leds aren't needed, but there's some problems still in the designs I came up with.

Also, all systems, LED and otherwise, hold an additional problem: polarization. Unless you have a method to keep track of polarization, a simple polarization filter (like the ones found on nice sunglasses, although preferably a better one, and without any tinting like sunglasses provide) could make you stand out like a sore thumb - actually making you *more* obvious in your surroundings, instead of less. Again, polarization can be shifted (via reflection, transmission through various substances, etc), but trying to match up polarizations makes this hard task even harder.