Phys.org October 20, 2020
Going beyond an improved colour gamut, an asymmetric colour contrast, which depends on the viewing direction, and its ability to readily deliver information could create opportunities for a wide range of applications, such as next-generation optical switches, colour displays, and security features in anti-counterfeiting devices. Researchers in South Korea propose a simple Fabry–Perot etalon architecture capable of generating viewing-direction-sensitive colour contrasts and encrypting pre-inscribed information upon immersion in particular solvents. Based on the experimental verification of the theoretical modelling, they have discovered a completely new and exotic optical phenomenon involving a tunable colour switch for viewing-direction-dependent information delivery, which they define as asymmetric optical camouflage…read more. Open Access TECHNICAL ARTICLE
Liquid-permeable BEE for Janus colouration. Credit: Light: Science & Applications volume 9, Article number: 175 (2020)