MA Heng;FU Xin-pu;ONNAGAWA Hiroyoshi. Millimeter Wave Frequency Dependency of Dielectric Constant in Liquid Crystal Materials[J]. 液晶与显示, 2009,24(6): 779-782
MA Heng;FU Xin-pu;ONNAGAWA Hiroyoshi. Millimeter Wave Frequency Dependency of Dielectric Constant in Liquid Crystal Materials[J]. 液晶与显示, 2009,24(6): 779-782DOI:
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.
关键词
Keywords
references
. Mada H, Kobayashi S. Wavelength and voltage dependences of refractive indices of nematic liquid crystals [J]. Mol. Cryst. Liq. Cryst., 1976, 33:47-53.
. Warenghem M, Grover C P. Dispersion curve measurement using Talbot bands [J]. Rev. Phys. Appl., 1988, 23(6):1169-1178.
. Abdulhalim I. Dispersion relations for the refractive indices and the effective birefringence of liquid crystals [J]. Mol. Cryst. Liq. Cryst., 1991, 197:103-108.
. Wu S T, Wu C S, Warenghem M, et al. Refractive index dispersions of liquid crystals [J]. Opt. Eng., 1993, 32(8):1775-1780.
. Mada H, Nishikawa A. Dielectric properties of n-pentyl-p-n-cyanobiphenyl in 2 wide frequencies range [J]. Jpn. J. Appl. Phys., 1993, 32(7B):L1009-L1010.
. Mada H, Ryuzaki M. Ion influence on nematic liquid crystal cell impedance at low frequency [J]. Jpn. J. Apl. Phys., 1995, 34(9A):L1134-L1136.
. Nakanowatari J, Ono K. Effect of the thickness alignment layer on the low frequency dielectric dispersion of a nematic liquid crystal [J]. Jpn. J. Appl. Phys.,1996, 35(1B):L111-L113.
. Born M, Wolf E. Principles of Optics [M]. Oxford: Pergamon Press, 1991:323-367.
. Nose T, Honma M, Nozokido T, et al. Simple method for the determination of refractive indices and loss parameters for liquid-crystal materials in the millimeter-wave region [J]. Appl. Opt., 2005, 44(7): 1150-1155.