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.
Bibliographical noteFunding Information:
This work was supported in part by KIST intramural grants (Nos. 2E30506, 2V07880, and 2E30140). S.-Y.L. is supported by the Basic Science Research Programme through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2020R1A4A1019518). Seok Chung was supported by NRF grant funded by MSIT (2020R1A2B5B03002005). I.S.K. acknowledges support from the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. 2020R1C1C1013474).
© 2020, The Author(s).
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics