UC Berkeley July 23, 2020
At certain temperature tungsten-doped vanadium dioxide can phase shift from an insulator to a metal. An international team of researchers (US Berkeley, Singapore, China) created special structures made from delicately engineered thin films of tungsten-doped vanadium dioxide. With judicious engineering of the doping profile, the insulator-metal phase transition can even out, allowing the substance to emit a constant level of thermal radiation over wide range of temperature variations (15-70 degrees Celsius). This state of equilibrium prevents a camera from detecting the true infrared signals that an object normally emits around room temperature. The coatings can be manipulated in a such way that a person trying to view the object would instead see a false image. According to the researchers this method provides better, more consistent camouflage because the product is mechanically flexible, power free and inherently self-adaptive to temporal fluctuation as well as spatial variation of the target temperature. The technology applications in military and intelligence agencies, and might incubate future encryption technology, allowing information to be safely concealed from unauthorized access…read more. TECHNICAL ARTICLE
The letters C-A-L appear cool even when the environment is hot… the decoy could fool infrared cameras into perceiving a designated temperature rather than the actual temperature of the object. (Kechao Tang image)