National Yang Ming Chiao Tung University

Ru-Pin Chao

Ci-Ling Pan

Cho-Fan Hsieh

Yu-Chien Lai

Hsin-Ying Wu

Chao-Yuan Chen

The Terahertz Polarizer structure of the present invention comprises of: A pair of parallel quartz layers for forming a rectangular cube with internal space, then a birefringent liquid crystal is placed in the internal space and sealed, and a pair of permanent magnets with reverse polarities are placed at both sides of the pair of fused silica layers.

Structure of polarizing terahertz wave device

Alignments of liquid crystal are obtained. A transparent magnetic thin film provides a homeotropic alignment of liquid crystal molecules. Or, a homeotropic or homogeneous alignment having an adjustable pretilt angle is further obtained through rubbing the transparent magnetic thin film. The present invention has a simple procedure with a low cost. The present invention is used in equipment with a plasma source while providing high transmittance, hardness and insulation. And the transparent magnetic thin film has potential uses in the applications of non-contact multi-domain alignment without extra procedure for alignment treatment.

Method of alignments of liquid crystal employing magnetic thin films

The present invention provides a tunable terahertz (THz) wavelength selector device, which includes a fixed phase retarder, a tunable phase retarder and a pair of linear polarizers to form a unit. The fixed phase retarder and tunable phase retarder basically utilizes liquid crystals to provide phase retardation, moreover, utilizing birefringence phenomenon possessed by liquid crystals can provide adequate phase retardation. The fixed phase retarder utilizes horizontal orientation of liquid crystal cell to provide fixed phase retardation, while the tunable phase retarder however utilizes homeotropic liquid crystal cell and a rotatable magnet to provide a tunable phase retardation, wherein the tunable phase retarder can provide the positive or negative phase retardation relative to the fixed phase retarder, based on the direction of the magnet's rotating axes and totally use the entire tunable range into adjusting frequencies which can pass through. Besides, the present invention can also serially connect multiple units described above so as to achieve a narrow enough band-pass bandwidth.

Growing community of inventors

Hsinchu, Taiwan

Ru-Pin Chao