Man has wanted the ability to turn invisible since ancient Greece, with many mythological literature featuring a magical headdress worn by gods and goddesses that allowed the wearer to disappear from sight. This fascination has peaked within the last several decades due to various movies and literature, the most prominent being Harry Potter. The US military had come close to developing technology that could realize this fantasy, but they never really got as close as researchers at the US Department of Energy’s Lawrence Berkeley National Laboratory recently have.
“This is the first time a 3D object of arbitrary shape has been cloaked from visible light.” says lead researcher Dr. Xiang Zhang.
The material works through the use of “metamaterials”, materials engineered to have properties that aren’t found in nature. In the case of the invisibility cloak, features that are much smaller in size than that of the wavelength of light allows it to physically re-route the light waves coming in. It’s crafted out of copper tape and polycarbonate, a material regularly found in DVD’s and CDs. The result is a cloak that has a minuscule pattern, like a finely checkered shirt, that nullifies the waves bouncing off of it, reports CNN.
“Each antenna is designed to react with the light and scatter it back. They actually delay the light, delay the reflection, in such a way that every point of your face would reflect light as if from a flat surface, like a mirror.” explains Dr. Zhang.
In an experiment, the researchers covered a foot long cylinder with the material. Once cloaked, microwave detectors could no longer distinguish it, however it was still visible to the naked eye. The device is still in the very early stages of development, and it only truly works in a limited range of light waves, with microwaves being the most effective. Though in the near future, the same principal will work with the range of perceptible light, says researchers.
For now it would only work if the person wearing it remains completely still. If the wearer moves it disrupts the metamaterial’s ability to redirect the light. So we’re still quite far from imitating magic with science, but we’re certainly getting there. How this technology would be used isn’t exactly clear, but one can assume it would be in a military context.