New coating hides people or heat-emitting objects from infrared cameras
A new coating that makes it possible to hide heat-emitting objects or even living things from infrared cameras was developed by a group of engineers at the University of Wisconsin-Madison. Infrared cameras work on a physical phenomenon that is virtually ubiquitous and uncontrollable: the hotter the object, the brighter and better it becomes infrared.
The new coating is made of samarium nickel oxide, a material that allows decoupling the phenomenon of temperature from that of thermal light emission in a solid object, as explained by Mikhail Kats, professor of electrical and computer engineering at the aforementioned university. The same scientist adds: “We have made a coating that ‘breaks’ the relationship between temperature and thermal radiation in a very special way. In essence, there is a temperature range within which the power of the thermal radiation emitted by our coating remains unchanged”.
What this coating has is emitting a fixed amount of heat radiation independently of its temperature level. By doing this, it basically cancels out the radiation of the body behind it. At the moment the researchers have come to act at a relatively small temperature range, between 105 and 135 °C but the scientists themselves are doing further research to improve this range and to allow this new coating to be used in various applications.
The first, of course, could be camouflage, an interesting option especially in the military field. However, further applications could also be made in the area of simple privacy to allow people, with special clothes made of this material, not to be intercepted by these cameras that can detect people even at night and in complete darkness.
As Alireza Shahsafi, a student in Kats’ lab and one of the authors of the study that appeared in Proceedings of the National Academy of Sciences, explains, one can certainly imagine a future in which infrared cameras are even more common than they are today, so much so that more and more people will want not to be intercepted. Such a material, then, would prove to be very useful because it could be easily adapted to a suit or even a vehicle to act as a “shield” in the name of privacy.