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Asymmetric optical camouflage: tuneable reflective colour accompanied by the optical Janus effect.

ABSTRACT: 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. Here, we 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 (optical camouflage). Based on the experimental verification of the theoretical modelling, we have discovered a completely new and exotic optical phenomenon involving a tuneable colour switch for viewing-direction-dependent information delivery, which we define as asymmetric optical camouflage.

SUBMITTER: Kim T

PROVIDER: S-EPMC7569085 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Asymmetric optical camouflage: tuneable reflective colour accompanied by the optical Janus effect.

Kim Taehyun T Yu Eui-Sang ES Bae Young-Gyu YG Lee Jongsu J Kim In Soo IS Chung Seok S Lee Seung-Yeol SY Ryu Yong-Sang YS

Light, science & applications 20201019

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. Here, we propose a simple Fabry-Perot etalon architecture capable of generating viewing-direction-sensitive colour contrasts and encrypting pre-inscribed information upo ...[more]

PMID: 33088492

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