Physical unclonable functions for one time password generation based on the exploitation of cholesteric liquid crystals

The phenomenon of frauds is increasing exponentially, especially where counterfeiting of goods, medicine and cyber-attacks are concerned, thus causing money and data theft and requiring a constant research of solutions. During the last decade, results have been obtained in the anti-counterfeiting field with the realization both of physical and/or digital solutions. Here, we propose the use of Cholesteric Liquid Crystals (CLCs) for the fabrication of a physical unclonable function (PUF) pattern obtained by applying an electric field. Each pattern is analyzed through an image recognition algorithm to demonstrate its uniqueness and then stored to create a secure server. Through a binarization process, unique, randomized CLC optical textures are converted into tamper-resistant binary One Time Passwords (OTPs), thus combining physical unclonability with next-gen encryption to fight digital fraud.