National Sun Yat-sen University of Kaohsiung

Duan-Yi Guo

Tsung-Hsien Lin

Cheng-Chang Li

Li-Min Chang

Kuan-Wu Lin

Heng-Yi Tseng

Hung-Chang Jau

Chun-Ta Wang

Yu-Chieh Li

Cheng-Kuan Wu

A cholesteric liquid crystal polarizing grating includes two substrates, two alignment layers, and a liquid crystal layer. An interlayer space is formed between the two substrates. The two alignment layers are respectively located on inner surfaces of the two substrates facing the interlayer space. Alignment directions of the alignment layers are periodically arranged. An alignment plane of each alignment layer is divided into a plurality of rows. The alignment directions in a same row are the same, and the alignment directions in adjacent rows rotate relative to each other. The plurality of rows with the alignment directions rotated by 180 degrees defines a grating period. The liquid crystal layer is located in the interlayer space. Liquid crystal molecules adjacent to the two alignment layers are arranged following the alignment direction of each alignment layer to form a polarizing grating with the grating period.

Cholesteric liquid crystal polarizing grating

A light reflecting device includes two substrates and a liquid crystal layer. The two substrates are parallel to each other and respectively electrically connected to a voltage source to generate an electric field therebetween. Each of the two substrates has an inner surface having a horizontal orientation. The liquid crystal layer is formed by liquid crystal materials filled between the two substrates. The liquid crystal materials include liquid crystal molecules and ions of salt species. The liquid crystal molecules are at least formed by negative liquid crystals and chiral molecules. The liquid crystal layer is respectively switched to a diffuse reflection state and a specular reflection state by applying the electrical field generated by the voltage source in a first frequency and a second frequency. The second frequency is higher than the first frequency.

Light reflecting device and switching method thereof

An electrically controlled polarization rotator is disclosed. The electrically controlled polarization rotator includes two substrates and a liquid crystal layer located between the two substrates. The two substrates have a homogeneous alignment and a homeotropic alignment respectively. A distance between the two substrates is a liquid crystal thickness. A switching electric field which is adjustable is provided between the two substrates. A polarized light is incident on the substrate having the homogeneous alignment. A polarization direction of the polarized light is orthogonal or parallel to an alignment direction of the substrate having the homogeneous alignment. A birefringence of the liquid crystal layer multiplied by the liquid crystal thickness and further divided by a wavelength of the polarized light is greater than 10. The polarization direction of the polarized light is rotated corresponding to an intensity of the switching electric field in the liquid crystal layer.

Electrically controlled polarization rotator

A multi-function light-adjusting glass includes first and second substrates delimiting an intermediate space therebetween, a light-adjusting layer disposed in the intermediate space, and a first polarizing board located at an outer side of the first substrate away from the intermediate space, and a second polarizing board located at an outer side of the second substrate away from the intermediate space. Each substrate includes an electrically conductive film on an inner surface of the substrate facing the intermediate space, and an alignment film disposed between the electrically conductive film and the intermediate space. The two alignment films respectively have two alignment directions orthogonal to each other. The light-adjusting layer includes liquid crystal molecules and salt-in ions. When the two electrically conductive films apply a voltage to the light-adjusting layer, the liquid crystal molecules are in a discontinuous and chaotic arrangement and cause an incident light to scatter in the light-adjusting layer.

Growing community of inventors

Kaohsiung, Taiwan

Duan-Yi Guo