Advances on holographic polymer nanocomposites

Holographic Plastics with Liquid Crystals

“…(b) Schematic illustration on the characterization of diffraction efficiency in reflection gratings. Adapted with permission from ref . Copyright 2022 Chinese Journal of Applied Chemistry.…”

“…Nevertheless, the photopolymerization is generally very fast, particularly at a high dose of laser irradiation, which thereby dramatically hampers the LC diffusion and phase separation. 45 To address this issue, extensive research has been conducted by choosing different photoinitiators, monomers, and LCs along with incorporating nanoscale additives. Several examples will be provided in the following sections due to the limited space.…”

“…Holography, with Nobel Prize fame, is a unique technique capable of recording all of the wavefront information and later reconstructing it with a probe beam, which was pioneered by Dennis Gabor in 1948 . Despite extensive research on various holographic technologies such as computer-generated holography, − metasurface holography, − and embossed holography, volume holography by laser interference remains exclusive to create flexible, lightweight, and sophisticated optical elements with ultrafine structures in the micro/nanoscale. − To this end, plastics are widely utilized due to their low density, ease of large-scale processing, exceptional flexibility, and attractive long-term stability. − The produced holographic plastics have also been regarded to be indispensable for future flexible and lightweight three-dimensional (3D) displays, augmented reality (AR), high-density data storage, and advanced anticounterfeiting. − However, the refractive index modulation of holographic plastics is relatively small, which has become a major bottleneck for practical applications. − …”

Ion-Conducting Composites of Polymers and Nematic Liquid Crystals

“…PDLCs comprise micrometer- and submicrometer-sized NLC droplets in a continuous polymer matrix. PDLC electro-optical thin films are currently employed for smart glasses, 3D displays, and tunable optical modulators, in flexible soft-matter photonics, diffractive and adaptive optics, lasers, sensors applications, and biomedical devices, for advanced anticounterfeiting, and in augmented and virtual reality, among others. − Besides PDLCs, another type of polymer/LC composite has been developedthe polymer-stabilized LC (PSLC). ,, In contrast to PDLCs in which both the polymer and the LC phases are separated, in PSLCs a small amount of cross-linked polymer is dispersed in a continuous LC phase, and the LCs and polymer form an interpenetrating three-dimensional structure.…”

“…In the past decade, various kinds of advanced multifunctional composite materials from polymers and liquid crystals (LCs) have been developed and thoroughly investigated due to their important properties. − Such soft or soft-solid materials have found a wide variety of applications, the most popular being the electrically controllable large-scale screens, projection systems, 3D digital displays, light shutters, switchable windows, and energy-saving windows. − The thermotropic LCs are mesogenic materials with different LC phases as a function of temperature. They combine the order of crystalline solids and the flowing properties of liquids.…”