Electrically responsive photonic crystals with bistable states for low-power electrophoretic color displays

Abstract

Electrically responsive photonic crystals are promising materials for electrophoretic color displays with better brightness and color saturation. However, electric field must always be applied to maintain the specific colors, which brings concerns about the power consumption and signal stability and reversibility. Here, we show an electrically responsive photonic crystal with two stable states at 0 V, which are the colored state or the colorless state with ordered or disordered particle arrangement. The color state can be reversibly switched by applying a short-time electrical field, just like in the case of commercial electrophoretic ink. With optimized recipe and electric field, the photonic crystals encapsulated in the prototype display panel are proved to have potentials in high resolution, multi-color, and greyscale display, which lays down a firm basis for reflective displays with low power consumption and good visibility.

Micro/Nanorobotic Swarms: From Fundamentals to Functionalities

“…Alternatively, microrobotic swarms can generate convective flows , and navigate through a confined environment (e.g., polypropylene microfiber network) to enable and accelerate the catalytic performances. Microrobotic swarms also provide a means to display desired images, wordings, and colors. ,,,,,− By controlling the UV exposure, photoactive nanoparticles have been aggregated into desired patterns. , The patterns were self-erasable, as the nanoparticle aggregates fell apart in the absence of UV irradiation. More recently, photochromic colloidal swarms have been demonstrated to adapt to the colors of incident lights and they formed reconfigurable colored patterns (Figure I) .…”

Low-voltage and wide-tuning-range SiO2/aniline electrically responsive photonic crystal fabricated by solvent assisted charge separation

“…Various stimuli, including electric field, [1][2][3][4][5][6][7] magnetic field, [8][9][10][11] thermal interaction, [12][13][14] mechanical force, [15][16][17] and the chemical environment, [18][19][20][21][22][23][24] are capable of changing the color of photonic crystals. Considering the feasibility of controlling the electric field on a miniaturized scale, an electrically responsive photonic crystal (ERPC) was an ideal system for realizing instant and accurate tuning of colors.…”

Rewritable Structurally Colored Paper Based on Hollow SiO2–Polyurethane Composite Photonic Crystal Film

“…Photonic crystals based on the periodic arrangement of two components with a differing refraction index, which can generate structural color arising from the selective reflection of nature light according to the Bragg diffraction, have attracted considerable attention in recent years. − Compared with chemical dyes, structurally colored materials are remarkable for their color durability and resistance to photobleaching since they are originated from the microstructure instead of chemical molecules. Responsive photonic crystals with a tunable lattice constant or refractive index and the tunable stop band can be readily altered using various external forces such as electric field, − magnetic field, − temperature, − solvent, − and mechanical stretching or pressing . By tuning the lattice constant or refractive index, full spectral ranged reflected colors are easily achieved on a responsive photonic crystal film.…”