Studies on the electro‐optical properties of chiral nematic liquid crystal/aerosil particle composites

Chiral nematic liquid crystal (N*‐LC)/aerosil particle (AP) composites were prepared. After the composite was sandwiched between ITO glass substrates, the inner surfaces of which had been treated for homogeneous orientation of LC molecules, the LC molecules tended to be aligned with planar texture. Upon the application of an electric filed, a focal conic texture with memory effect was induced and the composite exhibited light scattering. An electric field‐induced homeotropic state was obtained after the application of a high electric field. The effects of the content of the APs and the pitch length of the N*‐LC on the transmittances of the initial state and the focal conic texture, the driven voltage and the memory effect were investigated.

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