WANG Yong-chao, ZHANG Zhi-dong, ZHOU Xuan. Study of light leakage induced by the elastic anisotropy of the nematic liquid crystal[J]. , 2015,30(6): 949-959
WANG Yong-chao, ZHANG Zhi-dong, ZHOU Xuan. Study of light leakage induced by the elastic anisotropy of the nematic liquid crystal[J]. , 2015,30(6): 949-959 DOI: 10.3788/YJYXS20153006.0949.
Study of light leakage induced by the elastic anisotropy of the nematic liquid crystal
we show the reasons for light leakage in the nematic liquid crystal (NLC) cells with bulk defect structure in the dark state and the influence of the anchoring conditions on it. Firstly
we give three models of NLC cells with different director distribution at the initial state. Secondly
based on the Landau-de Gennes theory
we calculate the defect dynamics of the director field and get the director distribution in the cross-section of the cells at equilibrium state. Finally
we express the director distribution in the form of light transmittance with Jones Calculus. Without applied field
the simulation results indicate that the cells with bulk defect have spontaneous twist structure under the condition of
L
2
/
L
1
1(
K
22
/
K
11
2/3)
which leads to light leakage of the cells. The intensity of light leakage varies with defect structures and anchoring conditions at the boundaries. Our models can explain the light leakage in the NLC cells induced by the bulk defect in the dark state
and the results show a good agreement with the phenomena found in the process of industry manufacture.
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references
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