Multifunctional Liquid Crystal Smart Glass with Light Field Shaping, Dimming, and Scattering Control

Abstract

Glass with multiple light control functions has received considerable attention in recent years. This study demonstrates a multifunctional smart glass composed of hybrid‐aligned ion‐doped nematic liquid crystals (LCs). In the absence of an applied electric field, the hybrid aligned LC is transparent and can be used for light field shaping. The transmittance of the glass can be limited to less than 2% with a 1D oblique viewing angle of >50°. In addition, by varying the frequency and strength of the electric field applied to the device, tinted and scattering states can be achieved with polarization rotation and the electrohydrodynamic effect, respectively. The nonscattering tinted state can control transmittance in the range from 38% to 0.2%. The scattering state provides a 99% high‐haze performance. These results demonstrate that the proposed smart glass can be used for meeting the novel requirements of the next generation of green and smart buildings and vehicles.

Liquid crystals for optical switches, smart windows, reconfigurable/tunable meta-structures, micro-resonator coupling and plasmonic nanostructures

“…Instead of the optical electric field, an external applied AC field is used to induce index or birefringence changes needed to focus, rotate polarization, or switch the propagation direction of light. For some smart window applications, switching between a clear and a translucent/opaque/reflective state is desired and can be mediated by several mechanisms quite distinct from the foregoing discussions, namely, absorption, scattering, and combination of scattering & absorption [22][23][24][25][26][27][28][29][30].…”

Viewing Direction-Tunable Light Control Using Liquid Crystal Film for Simultaneous Implementation of Automotive Display Visibility and Safety

“…They are placed in cockpits in the form of clusters, center information displays, and codriver displays (CDDs), and have been integrated as large displays. In addition, their mounting areas have expanded from interior regions to window and exterior regions. − In addition to the change in the shape of the displays, there are numerous demands for the expansion of their functions, such as providing simple driving and traffic information, in addition to entertainment, e.g., watching movies, playing games, and shopping, particularly through the CDD panel. − Nevertheless, the implementation for providing both information and entertainment in automobiles is limited due to the absence of technologies that conform to legal regulations for safety, which prohibit the viewing of videos in a driving car. Therefore, technologies that are capable of providing convenience to occupants, while ensuring safety by preventing driver distractions, are required.…”

Hybrid-Aligned Liquid Crystal Polymers Adhered to the Polarizing Film or Doped with Dichroic Dye for Display Privacy Protection

“…In recent years, liquid crystals (LCs) and polymer dispersed LCs (PDLCs) units with hybrid alignment have shown promising applications in various fields, such as smart windows and displays, thanks to their optical anisotropy induced by special orientation. − Among these, some research has proposed that a sandwich structure consisting of a small-molecule LC cell with a hybrid arrangement and polarizers can reduce light transmittance at predetermined azimuth and polar angles without affecting the transmission of light in the normal direction. This configuration has demonstrated potential applications in angle-switching LCDs and one-dimensional light field-shaping windows. ,, However, this requires two additional layers of polarizers, and the integration of a small-molecule LC cell adds extra thickness and weight, which is unfavorable for industrial commercialization. Therefore, by utilizing the polarizer inside the display panel, it is possible to release one of the polarizers in this sandwich-like structure and efficiently make use of the backlight of the screen.…”

“…This configuration has demonstrated potential applications in angleswitching LCDs and one-dimensional light field-shaping windows. 17,18,26 However, this requires two additional layers of polarizers, and the integration of a small-molecule LC cell adds extra thickness and weight, which is unfavorable for industrial commercialization. Therefore, by utilizing the polarizer inside the display panel, it is possible to release one of the polarizers in this sandwich-like structure and efficiently make use of the backlight of the screen.…”