Unclonable Micro‐Texture with Clonable Micro‐Shape towards Rapid, Convenient, and Low‐Cost Fluorescent Anti‐Counterfeiting Labels

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 17; no. 30; pp. e2100244 - n/a
• Main Authors: Lin, Yuhong, Zhang, Hongkun, Feng, Jingyun, Shi, Bori, Zhang, Mengying, Han, Yuexing, Wen, Weijia, Zhang, Tongyi, Qi, Yabing, Wu, Jinbo
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.07.2021
• Subjects: anti‐counterfeiting; Counterfeiting; divide‐and‐conquer; Engraving; evaporative assembly; Fluorescence; laser engraving; Nanotechnology; Object recognition; Perovskites; physical unclonable function; Reagents; Texture; Thin films
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202100244

An ideal anti‐counterfeiting label not only needs to be unclonable and accurate but also must consider cost and efficiency. But the traditional physical unclonable function (PUF) recognition technology must match all the images in a database one by one. The matching time increases with the number of samples. Here, a new kind of PUF anti‐counterfeiting label is introduced with high modifiability, low reagent cost (2.1 × 10−4 USD), simple and fast authentication (overall time 12.17 s), high encoding capacity (2.1 × 10623), and its identification software. All inorganic perovskite nanocrystalline films with clonable micro‐profile and unclonable micro‐texture are prepared by laser engraving for lyophilic patterning, liquid strip sliding for high throughput droplet generation, and evaporative self‐assembling for thin film deposition. A variety of crystal film profile shapes can be used as “specificator” for image recognition, and the verification time of recognition technology based on this divide‐and‐conquer strategy can be decreased by more than 20 times. A fluorescent anti‐counterfeiting label with low reagent cost (2.1 × 10−4 USD), simple and fast authentication (overall time 12.17 s), and high encoding capacity (2.1 × 10623) is presented here with its identification software. The diversified and clonable micro‐shapes engraved by the nanosecond laser can help the software to classify and accelerate the recognition speed of unclonable micro‐texture.