Active Full-Color Generation Based on a Liquid Crystal-Integrated Plasmonic Metasurface

Structural colors based on metasurfaces outperform traditional pigments and dyes in terms of nonfading, high spatial resolution, and high stability, usually incorporating active materials for tunability. Liquid crystals (LCs) are suitable for tunable structural color design due to their large birefringence and fast modulation by external stimuli. However, most LC-integrated structural colors focus on tailoring the polarization angle of incident light to generate two colors and their mixing. Herein, a scheme of full-color generation based on a plasmonic metasurface integrated with LCs utilizing the combination of the polarization angle rotation effect of the twisted-nematic LCs and the refractive index modulation through the realignment of the LCs near the metasurface is demonstrated. Based on the proposed structural color method, full-color generation of a record color gamut of 60.7% standard Red Green Blue region, equivalent to 43% National Television Standards Committee area, in the LC-integrated metasurface, has been numerically realized by tuning the bias voltage of the LCs in reflection. The achieved color gamut is nearly 4 times wider than the previously reported result. The proposed active full-color generation metasurface shows great potential in applications for low-power reflective color display, anticounterfeiting, and optical encoding.