University of Pennsylvania researchers have learned to use the optical properties of cicada brochosomes to create the world’s smallest QR code. The authors of the study harnessed infrared light, turning it from a carrier of energy into a carrier of information.
Brochosomes are small granules that resemble soccer balls in appearance. Inside them there are nano-sized cavities. The peculiarity of this design is that it absorbs light from the inside, but does not reflect it to external structures. Biologists suggest that this property of the particles allows cicadas to blend into their surroundings. University staff suggested that the material could be used to create a microscopic QR code.
The team simulated two versions of the design: one with cavities to absorb light, and one without them. Scientists quickly realized that if they connected both structures together, one would emit more energy and appear brighter in the infrared spectrum than the other. This fact led to the development of the world’s smallest QR code.
The QR code can only be read using an infrared camera. A pattern smaller than 2% of an inch can only be seen under a microscope. Now scientists plan to study ways to scale it up for subsequent commercial use.
