【摘要】 基于液晶材料的器件成为毫米波及太赫兹波领域的重要方向之一,文中总结了毫米波太赫兹波液晶器件的研究进展,介绍了液晶移相器的基本原理及应用,分析了液晶介电常数的主要测试方法,如传输线/反射法、谐振腔法、自由空间法、时域法等,比较了不同方法的测试频率范围和优缺点,并给出了向列相液晶材料在微波毫米波及太赫兹波段的介电常数的主要测试结果。更多还原

【Abstract】 With the development of technology,devices based on liquid crystal materials have been increased considerably in the terahertz fields. This paper presents the research progress of terahertz(THz) liquid crystal devices,and the basic principles of liquid crystal phase shifter. In addition,several methods for the measurement of dielectric constants of liquid crystal are introduced,such as the transmission lines/reflection method,the resonant cavity method,the free-space method,the time domain method. The difference,involves range and relative merits,of those methods are compared. This overview also has revealed some experimental results of permittivity of the liquid crystal,which are measured at the different frequency ranges.更多还原