Controlling brightness in full color nanoprinting by all-dielectric metasurfaces

Structural colorations with all-dielectric metasurfaces provide a dye-free approach for integrated sub-wavelength color generation with enhanced stability and environmental friendliness. However, it remains challenging to simultaneously tailor all the elementary color functions, hue, saturation, and brightness, in a simple platform. Here, we report a generic principle to create bright-field full-color nanoprinting with brightness control by using all-dielectric metasurfaces consisting of arrays of Si elliptical nanopillars. It is demonstrated that the lower order Mie resonances in the reflection spectra redshift with the sizes of the elliptical nanopillars when the incident light polarization is fixed along the major or minor axes. By designing the structure carefully, basic colors, such as red, green, blue, and yellow, are obtained across the visible spectrum. Experimental measurements show that the fabricated colors are independent with respect to the viewing angle owing to the Mie resonance origin. Moreover, we demonstrate that, by varying the angle of either the polarizer or the analyzer, the resonant wavelengths keep invariant while the reflection intensity decreases, leading to the tuning of the brightness of colors from bright to dark without changing the hue and saturation. Our scheme provides a simple yet general approach for the full hue, saturation, brightness control of structural colors, holding great potential in diverse applications, such as anti-counterfeiting technologies, 3D displays, and information storage.