液晶与显示2016，Vol.31Issue(6)：547-552,6.DOI:10.3788/YJYXS20163106.0547
弱磁场中向列相液晶TEB30 A薄膜自衍射现象研究
Self-diffraction effect of nematic liquid TEB30A film in weak magnetic field
摘要
Abstract
The far-field diffraction characteristics was studied in the different weak magnetic fields(0, 0.464 9,0.506 2 and 0.518 5 T)with the low power He-Ne laser of 1.5 mW(632.8 nm)being normal incident on the film of nematic liquid crystals TEB30A.The experiment results showed that the film of nematic liquid crystals TEB30A can produce diffraction in the four weak magnetic fields of 0,0.464 9, 0.506 2 and 0.518 5.The diffraction pattern could obviously be changed with the increasing of the magnetic strength.The number of diffraction rings increased,the width of diffraction rings became wide,and the diffraction field expanded outward.At the magnetic strength of 0.506 2 T,the interfer-ence stripes appeared on the diffracting rings.While the magnetic strength increased to 0.518 5 T, the interference stripes was becoming parallel.Under the effect of the weak magnetic field,the diver-gence of the laser beam was changed drastically in the far-field.Based on the Kirchhoff - Fraunhofer diffraction integral,the theoretical simulation results showed that,when the laser beam passed through the film of nematic liquid crystals TEB30A in the weak magnetic field,the transverse nonlin-ear phase would increase.With the weak magnetic strength increasing from 0 T to 0.518 5 T,the nonlinear phase increased from 4πto 20π.The weak magnetic field caused the nonlinear phase,resul-ting in the change of the far-field diffraction pattern.The change of the far-field diffraction pattern is also the change of the distribution of the transmitted light energy.Therefore,the technology of the weak magnetic field modulating the nematic liquid crystals can be applied to the areas of magnetic-op-tical switch and magnetic-optical limiters.关键词
低功率/正入射/向列相液晶TEB30A薄膜/弱磁场/衍射Key words
low power/normal incident/the film of nematic liquid crystals TEB30A/weak magnetic field/diffraction分类
数理科学引用本文复制引用
刘桂香,王雁冰..弱磁场中向列相液晶TEB30 A薄膜自衍射现象研究[J].液晶与显示,2016,31(6):547-552,6.基金项目
内蒙古自治区教育厅科学研究项目(No．NJZY12203) （No．NJZY12203）
