A reflective polarizer-free electro-optical switch using dye-doped polymer-stabilized blue phase liquid crystals.

We demonstrate a reflective polarizer-free electro-optical switch using dye-doped polymer-stabilized blue phase liquid crystals (DDPSBP-LC). At the voltage-off state, the dye molecules and liquid crystals form the structure of the double twist cylinders. As a result, the DDPSBP-LC is in dark state due to the combination of Bragg reflection and light absorption. At the voltage-on state, the blue phase structure is unwound locally. The DDPSBP-LC is then in bright state because of the small light absorption only. The applications of such a switch are shutter glass of 3D displays, and electronic papers.

A bistable polarizer-free electro-optical switch using a droplet manipulation on a liquid crystal and polymer composite film.

A bistable, polarizer-free, and reflective electro-optical switch based on a droplet manipulation on a liquid crystal and polymer composite film (LCPCF) is demonstrated. A color droplet on LCPCF can be manipulated by a wettability gradient owning to the distribution of LC directors anchored among the polymer grains on LCPCF. The contrast ratio is around 8:1 in a reflective mode. The potential applications of droplet manipulation are electronic papers and reflective displays.

Crucial effects of the anisotropy on optical field induced pattern formation in nematic liquid crystal films.

We present here the crucial effects of material anisotropy on optical field induced pattern formation in the one-feedback-mirror arrangement which utilizes the nematic liquid crystal film as the nonlinear medium. By using the quasi-static electric-field-biased planar-aligned homogeneous nematic liquid crystal (NLC) films, we observe both the hexagon and the roll patterns which can be switched optically due to the intrinsic anisotropic distribution of the threshold intensity. The anisotropy comes from the anisotropic nonlinear response of the NLC film and is the crucial factor for such a one-feedback-mirror system to form both the roll and hexagon patterns. The observed phenomena can be explained from the linear stability analysis of the governing diffusion-like equation. The experimental results indicate that the stable roll patterns are formed at low input light power and the stable hexagon patterns formed at high input power.