‘Stealth Sheet’ Hides Hot Objects From Infrared Detectors

Infrared cameras help drones find their targets, even in the dead of night or through smoke and fog. Hiding from such detectors could become much easier, thanks to a new cloaking material that renders objects and people practically invisible, say its developers.

“What we have shown is an ultrathin stealth sheet. Right now, what people use tends to be much heavier metal armor or thermal blankets,” said Hongrui Jiang, the Lynn H. Matthias Professor and Vilas Distinguished Achievement Professor of Electrical and Computer Engineering at the University of Wisconsin-Madison.

Warm objects like human bodies or tank engines emit heat as infrared light, and the new stealth sheet, described in Advanced Engineering Materials, offers substantial improvements over other heat-masking technologies, says the Wisconsin team. “It’s a matter of the weight, the cost and ease of use,” commented Jiang.

Measuring less than one millimeter wide, the thin sheet absorbs approximately 94 percent of the infrared light it encounters. Trapping so much light means that warm objects beneath the cloaking material become almost completely invisible to infrared detectors.

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