Scalable Multistep Imprinting of Multiplexed Optical Anti-counterfeiting Patterns with Hierarchical Structures

Multiplexed optical techniques with multichannel patterns
provide
powerful strategies for high-capacity anti-counterfeiting. However,
it is still a big challenge to meet the demands of achieving high
encryption levels, excellent readability, and simple preparation simultaneously.
Herein, we use a multistep imprinting technique, leveraging surface
work-hardening to massively produce multiplexed encrypted patterns
with hierarchical structures. These patterns with coupled nano- and
microstructures can be instantaneously decoded into different pieces
of information at different view angles under white light illumination.
By incorporating perpendicular nano- and microgratings, we achieve
four-channel encoded patterns, enhancing anti-counterfeiting capacity.
This versatile method works on various metal/polymer materials, offering
high-density information storage, direct visibility, broad material
compatibility, and low-cost mass production. Our high-performance
anti-counterfeiting patterns show significant potential in real-world
applications.