Unclonable anti-counterfeiting labels based on microlens arrays and luminescent microparticles

TL;DR

This paper introduces unclonable anti-counterfeiting labels using microlens arrays and luminescent microparticles that can be authenticated with standard smartphones, offering a simple and robust security solution.

Contribution

It presents a novel unclonable label design that enables authentication with common devices, reducing hardware complexity compared to existing methods.

Findings

Robust authentication demonstrated with 10,000 image comparisons

False authentication probability around 10^{-15}

Microlens arrays enable hardware-efficient unclonable labels

Abstract

Micron-scale randomness during manufacturing can ensure anti-counterfeiting labels are unclonable. However, this security typically comes at the expense of complex hardware being needed for authentication (e.g., microscopy systems). We demonstrate unclonable labels that can be authenticated using a standard light-emitting diode and smartphone camera. The labels consist of a microlens array laminated to a polymer film that is doped with luminescent microparticles. The micron-scale random overlap of focal volumes and microparticles leads to a pattern of bright points of visible light emission that can be easily imaged by a smartphone camera. 10 000 comparisons of images demonstrate that the labels can be robustly authenticated, and that the probability of a false authentication is on the order of $10^{-15}$. The ability for microlens arrays to simplify the hardware needed for authentication of unclonable labels is generalizable, and attractive for the implementation of unclonable labels in anti-counterfeiting systems.