Full Color and Grayscale Painting with 3D Printed Low-Index Nanopillars

Abstract

Sculpting nanostructures into different geometries in either one or two dimensions produces a wide range of colorful elements in microscopic prints. However, achieving different shades of gray and control of color saturation remain challenging. Here, we report a complete approach to color and grayscale generation based on the tuning of a single nanostructure geometry. Through two-photon polymerization lithography, we systematically investigated color generation from the basic single nanopillar geometry in low-refractive-index (n < 1.6) material. Grayscale and full color palettes were achieved that allow decomposition onto hue, saturation, and brightness values. This approach enabled the "painting" of arbitrary colorful and grayscale images by mapping desired prints to precisely controllable parameters during 3D printing. We further extend our understanding of the scattering properties of the lowrefractive-index nanopillar to demonstrate grayscale inversion and color desaturation and steganography at the level of single nanopillars.

Dewetting‐Assisted Patterning of Organic Semiconductors for Micro‐OLED Arrays with a Pixel Size of 1 µm

“…Figures S5b,c (Supporting Information) show the surface morphology and its corresponding height profile of a single dot in Figure 3c, respectively, which confirm that the NPB dot does not show the coffee ring effect and its size is merely ≈1 µm. Similar to the role of growth rate and growth time in the vacuum deposition, [ 32 ] the solution concentration can significantly influence the thickness of the NPB dots. The AFM image of the sample with concentration of 0.02 wt.% is presented in Figure S5d (Supporting Information).…”

Organic ultrathin nanostructure arrays: materials, methods and applications

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Liquid crystal-powered Mie resonators for electrically tunable photorealistic color gradients and dark blacks

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