Nano-meta-material full-color-gamut palette

The invention discloses a nano-meta-material full-color-gamut palette and a preparation method thereof. Electron beam photo-etching and reactive ion etching technologies are adopted; a transverse undercutting effect is utilized for obtaining a sub-wavelength periodic-structure array, which suspends above a dielectric layer, on a substrate; a metal film is deposited in the direction perpendicular to the substrate; and forming a metal nanostructured array-metal complementation nanostructured array film coupled structure. The sub-wavelength meta-material shows a mixed surface plasma resonance mode in a visible light spectrum and generates specific optical responses such as multiple resonance peaks, FANO resonance, angle-dependent spectrum adjustability and hundreds of thousands of times field enhancement, so that continuous and adjustable colors can be obtained in a structural unit. The nano-meta-material palette can generate full-color-gamut colors in a CIE chromaticity diagram, and the color pixel can be reduced to one hundred to hundreds of nanometers. The technology provided by the invention has an important application prospect in the fields such as product production, high-definition displaying, artistic creation, orientation sensing, photon codes and information storage.