液晶材料介电常数的毫米波频率特性研究

利用矩形波导管和向量分析仪,测量了几种液晶材料在26.5-40 GHz波段(Ka波)的介电常数。实验表明,1 kHz频率下呈现正、负介电各向异性的液晶材料,在该微波波段下都显示为正的介电各向异性。尽管这些材料的静介电常数各向异性相差很大,但是该微波波段对应的介电各向异性相差却很小,而且在26.5-38 GHz区间内几乎不随频率的增大而发生变化。

Abstract

A reflection-type liquid crystal (LC) test cell prepared with a K-band rectangular waveguide is used to determine the dielectric constant of LC materials. It is found that the usual LCs showing positive or negative dielectric anisotropy in 1 kHz reveal positive dielectric anisotropy in millimeter wave region. Furthermore,the high frequent dielectric anisotropy shows slight difference among the LCs and weakly frequency dependency between 26.5-37 GHz.

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马恒, 浮新普, 女川博義. 液晶材料介电常数的毫米波频率特性研究[J]. 液晶与显示, 2009, 24(6): 779. MA Heng, FU Xin-pu, ONNAGAWA Hiroyoshi. Millimeter Wave Frequency Dependency of Dielectric Constant in Liquid Crystal Materials[J]. Chinese Journal of Liquid Crystals and Displays, 2009, 24(6): 779.

液晶材料介电常数的毫米波频率特性研究

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