Gui-xing LIU, Hai LIN, Wei-xiu PANG, et al. Diffraction characteristics of nematic liquid crystal TEB 30 A grating doped with Sm2O3[J]. Chinese journal of liquid crystals and displays, 2018, 33(10): 851-856.
DOI:
Gui-xing LIU, Hai LIN, Wei-xiu PANG, et al. Diffraction characteristics of nematic liquid crystal TEB 30 A grating doped with Sm2O3[J]. Chinese journal of liquid crystals and displays, 2018, 33(10): 851-856. DOI: 10.3788/YJYXS20183310.0851.
Diffraction characteristics of nematic liquid crystal TEB 30 A grating doped with Sm2O3
the grating diffraction of the nematic liquid crystal TEB30A doped with Sm
2
O
3
is studied in the weak magnetic field. The results show that when the natural light passes through the sample of the proper proportion of Sm
2
O
3
/TEB30A in the weak magnetic field
the diffraction stripes appear in the far field. And the diffraction stripes will change dynamically with the increase of the intensity of the external magnetic field. The reason for producing the diffraction stripes is that the proper Sm
2
O
3
particles make the refractive index anisotropy Δ
n
of the nematic liquid crystal TEB30A exhibit the periodic distribution along the direction of the external magnetic field
which leads to the formation of the grating in the liquid crystal. When the external magnetic field varies in the intensity
the distribution of Sm
2
O
3
particles and liquid crystal molecules in the external magnetic field will change accordingly
which causes the period of the distribution of Δ
n
along the external magnetic field to change. As a result
the constant of the liquid crystal grating changes. Therefore
the diffraction stripes exhibit a dynamic effect. The simulation results show that the grating constant of the Sm
2
O
3
-doped nematic liquid crystal TEB30A decreases from 0.5 cm to 0.4 cm with the magnetic strength increasing from 0.464 9 T to 0.518 5 T. The technical method will greatly reduce the costs of the liquid crystal grating
and make operator work in a safe setting.
关键词
Keywords
references
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