The guys over at the Soldier Systems blog have a cool entry on face paints that can help a warfighter hide from enemy passive night vision systems.
Here's what they've got:
REDEYE and BLACKEYE camouflage compounds are formulated to eliminate or minimize hazardous reflected "green light" emitted from phosphorous screens on Night Vision Devices. Both of these compounds appear "invisible/black" when viewed by a passive enemy Night Vision Device.
GREENEYE face paint has a signature identical to green vegetation when viewed at night through a passive NVG and/or using an IR Illuminator. It also appears as green in visible light.
Now the site over at Orion Filters, which makes the NVG-beating paint, is all cagey and top secret...it takes a few steps to get to the info and I'm not sure how open the whole site really is. But the folks at Soldier Systems got the gouge somehow and if it's straight up (which usually their info is) this is a development that could have far reaching implications -- for American troops and their enemies.
It seems from Orion's write up that the face paint can help minimize the reflective light against an operator's face when he's using NVGs...and the green paint actually helps make him invisible to a vegitative backdrop.
There's already been the incorporation of "nano" fibers in Army and Marine Corps body armor that helps reduce reflectivity of ambient light, but that technology is by no means an invisible cloak. The addition of the Orion Filters face paint and other compounds, however, could help make US and allied forces truly "ghosts of the night."