Synthetic Camouflage Microparticles Inspired by Nature
Existing scientific literature was a blank page on the leafhoppers’ camouflage capabilities, but the engineers found in their own research that the particle surface of the brochosomes acts like a “metamaterial,” a type of material that could be used in cloaking devices. “The problem is that in the field, these leaf hoppers produce very little of this product, and it is very hard to collect,” Wong said. “But we had already produced large quantities of these structures in the lab, enough to put inside a machine to look at their optical properties.”
Wong and his engineering team published their study last month in Nature Communications. The study describes the designing of a synthetic material, via a process called electrochemical deposition, that mimics the leafhoppers’ brochosomes. The artificial brochosomes were then placed on leaves and observed with simulated insect vision. By capturing up to 99 percent of spectrum light detectable by insects, the artificial brochosomes successfully blended into their background.
The potential application of this discovery is widespread, from creating better batteries and anti-reflective coatings for sensor and cameras, to increasing light capture for solar cells. “This paper is more of a fundamental study,” Wong cautions. “In the future, we may try to extend the structure to longer wavelengths. If we made the structure a little larger, could it absorb longer electromagnetic waves such as mid-infrared and open up further applications in sensing and energy harvesting?”
So while Wong and his team look to be more than a few years off from building a human-sized invisibility cloak — sorry, Harry Potter fans — they are not the only ones exploring synthetic camouflage. Back in 2014, scientists at the University of Houston and University of Illinois (Urbana–Champaign) created an artificial light-reactive skin, inspired by the color-changing skin of an octopus, that could then be used as an electronic camouflage cloak. Also inspired by the shape-shifting, Cornell University engineers are currently developing their own camouflage method using programmable 3D, silicone materials.
But it would be, say, so much cooler to have a Cloak of Invisibility made out of synthetic bug sweat.