New 3D thermal invisibility cloak makes objects disappear from infrared cameras

Researchers at the University of Illinois Urbana-Champaign and the Technical University of Denmark built and tested a three-dimensional thermal cloak that makes objects appear absent to infrared cameras. Unlike earlier experimental cloaks, which worked on flat surfaces or only when heat flowed in a particular direction, this device can conceal complex shapes from heat arriving from many directions. It redirects heat around a protected region, preserving the temperature pattern outside while keeping the interior relatively uniform despite surrounding hot and cold conditions.

The cloak combines a 3D-printed aluminum lattice, which conducts heat efficiently, with cast rubber-like material that conducts it poorly. The lattice can be adjusted independently along three axes, allowing finer control of heat flow than previous designs. Infrared-camera tests showed that the device concealed intricate forms, including shapes resembling human heads. Potential uses include cooling microchips, protecting sensitive electronics from temperature extremes, and reducing the thermal signatures of people or equipment. The demonstrated cloak redirects external heat; it does not yet hide objects that generate heat themselves. Developing versions that actively manage heat produced inside the concealed region is the researchers’ next goal.