Scalable Multistep\nImprinting of Multiplexed Optical\nAnti-counterfeiting Patterns with Hierarchical Structures

Multiplexed optical techniques with multichannel patterns\nprovide\npowerful strategies for high-capacity anti-counterfeiting. However,\nit is still a big challenge to meet the demands of achieving high\nencryption levels, excellent readability, and simple preparation simultaneously.\nHerein, we use a multistep imprinting technique, leveraging surface\nwork-hardening to massively produce multiplexed encrypted patterns\nwith hierarchical structures. These patterns with coupled nano- and\nmicrostructures can be instantaneously decoded into different pieces\nof information at different view angles under white light illumination.\nBy incorporating perpendicular nano- and microgratings, we achieve\nfour-channel encoded patterns, enhancing anti-counterfeiting capacity.\nThis versatile method works on various metal/polymer materials, offering\nhigh-density information storage, direct visibility, broad material\ncompatibility, and low-cost mass production. Our high-performance\nanti-counterfeiting patterns show significant potential in real-world\napplications.