The Future of Secure QR Codes?
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The future of more secure QR codes is coming from a very unexpected direction- beetle shells. In a new study published in Advanced Optical Materials, scientists have developed a unique QR code that is anti-counterfeit by mimicking beetle shell coloration units.
According to the website Interesting Engineering, the innovation lies in combining commercially available pigments and unique, micro-sized cholesteric liquid crystals (CLCs), which possess extraordinary optical characteristics that allow them to selectively reflect light.
These materials possess a distinct molecular arrangement that interacts with light in a way that selectively reflects specific wavelengths, resulting in brilliant and varied colors.
A significant setback has been that despite scientists already lab-producing CLCs, the existing methods produce particles 100 micrometers in diameter, which is too large for most applications.
To overcome this challenge, a team of researchers from Nagoya University developed a solution that allows them to create much smaller spherical CLC particles with a more precise size control, measuring only a few micrometers in diameter.
In order to ensure consistent coloration, the researchers made the CLC particles spherical with a uniform size distribution, which is referred to as a monodisperse sphere.
This research has potential applications in creating more secure QR codes that are very difficult to replicate. These could utilize a property of CLCs called chirality, which refers to an object’s inability to be superimposed onto its mirror image due to its asymmetry.
Combining the color of spherical CLC particles with non-chiral pigments can produce an anti-counterfeiting QR code, which can only be read using a specific circular polarizer that allows certain light to pass through while blocking the rest.
The complete study was published in Advanced Optical Materials on July 9, according to information provided by Interesting Engineering.
