Cloaking devices — or “metamaterials” that scatter light — have been in university labs for years. But electrical engineers at U.C. San Diego claim they’ve solved a few key problems that make existing cloaks too obvious to the human eye.
First, let’s back up a moment. For the most part, metamaterials in cloaking devices are really thick and bulky. Far too bulky to be practical. The second problem is that the cloaks scatter light at lower intensities than when the light first touches the cloak — and all that low-intensity light is still within visual frequencies.
This means we perceive the area around those cloaks to be darker than its surroundings. It’s a dead giveaway.
But the U.C. San Diego engineers claim they’ve corrected those two issues in a recent paper. A very thin sheet of Teflon peppered with tiny dielectric cylinders can scatter light while being “almost lossless,” they claim, meaning there’s little to no difference in the intensity of light around the cloak.
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