Figure 27:

Dynamic structural color generation based on state of polarization of the incident light. (a) Schematic illustration of a polarization-dependent structural color device composed of arrays of TiO₂ elliptic nanopillars on a silica substrate. Periods along the x- and y-directions are denoted as P _x and P _y , respectively. (b) Color palettes under x- and y-polarized incidence with P _x and P _y varying from 300 nm to 400 nm. The nanopillar height is fixed as 300 nm and the filling ratios along the two axes are fixed as 0.6. Modified with permission [268]. Copyright 2018, Wiley-VCH. (c) Schematic of a polarization-selective color device, which is composed of an Ag mirror, a 1D Ag nano-grating layer, and a SiO₂ dielectric layer in between. TM polarization refers to electric field vector oscillating orthogonal to the grating direction, while TE polarization refers to electric field along the grating direction. (d) Optical images of a fabricated sample (showing Vincent van Gogh’s Sunflower) under TM- and TE-polarized illumination. Modified with permission [271]. Copyright 2020, American Chemical Society.