Versatile Authentication Using an Identifier Based On Optical Variable Nanostructures

Counterfeit electronic devices are increasingly recognized as severe threats for the security of cyber-physical systems. To authenticate and verify original devices and manufacturers, an optical authentication identifier based on a pixelated nano-substrate and a versatile intensity control layer is introduced in this article. The pixelated nano-substrate is comprised of color pixels based on optical variable nanostructures whereas the intensity control layer is designed to activate or deactivate specific color pixels. A response image acquisition device based on angle-dependent optical diffraction is constructed to register the authentic identifiers and to detect fake identifiers. In the registration stage, the extracted data (color information) of the authentic identifier is stored as a reference on a secured server. In the authentication stage, the data are obtained from a detected identifier and compared to the reference using block-by-block calculations of inter-distances and intra-distances. Experimental results and analysis show that the proposed scheme can accomplish the authentication of the optical identifier with high reliability and robustness.