Linearly polarized light with axial symmetry generated by liquid-crystal polarization converters

The photoalignment technology for the alignment of liquid crystal molecules has lately gathered much attention because its advantages over the conventional rubbing of polyimide coating and several different approaches for the realization of photoalignment have been presented. Due to its non-contact nature, a photoalignment eliminates generation of dust and electrostatic charges as well as mechanical damage to the surface. Up to now, the study of the photoalignment effect has been focused mostly on uniform substrates through linearly polarized light. With the aim to achieve such a bistable liquid crystal device by means of unpolarized UV light, we have proposed a single-step laser patterning on a photoalignment layer using a photomask to achieve an equilibrium configuration of LC molecules in contact with a periodically patterned substrate. The patterns were formed by stripes of alternating random planar and homeotropic anchoring in a sub-micron scale on the order of 0.5 micron. We proposed two possible configurations of bistable LC cells that can be obtained by combination of micro-patterned surface formed with alternating random planar alignment with either planar alignment or homeotropic alignment surfaces. In this study, we have investigated the alignment properties and switching behaviours of both proposed models.

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ON THE BEHAVIOR OF POLARIZED LIGHT IN TWIST-ORIENTED NEMATIC LIQUID CRYSTALS WITH ANISOTROPIC ABSORBENT DYE

Proceedings of the YSU A: Physical and Mathematical Sciences ◽

10.46991/pysu:a/2020.54.1.056 ◽

2020 ◽

Vol 54 (1 (251)) ◽

pp. 56-60

Author(s):

H.H. Hovakimyan

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Nematic Liquid Crystal ◽

Azimuthal Angle ◽

Polarized Light ◽

Transmitted Light ◽

Propagation Of Light ◽

Linearly Polarized ◽

Incoming Light

In this work we study the propagation of light in a twist-oriented pleochroic nematic liquid crystal with pleochroic dye. The dependence of the intensity of transmitted light on the azimuthal angle of the linearly polarized incoming light has been investigated experimentally. As a result, the role of absorption anisotropy has been identified.

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Nematic Liquid Crystal Waveguides for Spatial Control of Linearly Polarized Light Waves

2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) ◽

10.1109/piers-spring46901.2019.9017592 ◽

2019 ◽

Author(s):

V. S. Kabanava ◽

I. I. Rushnova ◽

E. A. Melnikova ◽

A. L. Tolstik

Keyword(s):

Liquid Crystal ◽

Nematic Liquid Crystal ◽

Polarized Light ◽

Spatial Control ◽

Light Waves ◽

Linearly Polarized

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Photocontrol of In-plane Alignment of a Nematic Liquid Crystal by a Photochromic Spiropyran Monolayer Absorbing Linearly Polarized Light

Chemistry Letters ◽

10.1246/cl.1992.1063 ◽

1992 ◽

Vol 21 (6) ◽

pp. 1063-1066 ◽

Cited By ~ 31

Author(s):

Kunihiro Ichimura ◽

Yuko Hayashi ◽

Norio Ishizuki

Keyword(s):

Liquid Crystal ◽

Nematic Liquid Crystal ◽

Polarized Light ◽

Linearly Polarized

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Геометрическая оптика твист-ориентированного нематического жидкого кристалла с анизотропным поглощением

Журнал технической физики ◽

10.21883/os.2019.11.48516.129-19 ◽

2019 ◽

Vol 127 (11) ◽

pp. 787

Author(s):

А.О. Овакимян ◽

А.Э. Айвазян ◽

Л.С. Асланян

Keyword(s):

Liquid Crystal ◽

Nematic Liquid Crystal ◽

Anisotropic Medium ◽

Light Propagation ◽

Light Wave ◽

Spatial Dynamics ◽

Polarized Light ◽

Asymmetric Effect ◽

Electric Component ◽

Linearly Polarized

The spatial dynamics of polarized light in a smoothly inhomogeneous anisotropic medium mixed with an anisotropic absorbing dye is analyzed. As such a medium, a twist-oriented nematic liquid crystal with a pleochroic dye was considered. In the geometrical-optical approximation, a system of coupled shortened equations for the Cartesian components of the electric component of the light wave is obtained. A system of coupled complex equations was analytically solved and the behavior of a linearly polarized wave in such a medium was analyzed in the case of both absorption and amplification. An asymmetric effect of these two processes on the spatial dynamics of light propagation in the medium is found.

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Oriental behaviour of some homologues of 4-n-pentyl-phenylthio-4′-n-alkoxybenzoate doped with dichroic dye

Opto-Electronics Review ◽

10.2478/s11772-008-0020-5 ◽

2008 ◽

Vol 16 (3) ◽

Cited By ~ 3

Author(s):

D. Bauman ◽

A. Zięba ◽

E. Mykowska

Keyword(s):

Liquid Crystal ◽

Order Parameter ◽

Liquid Crystalline ◽

Orientational Order ◽

Polarized Light ◽

Emission Spectra ◽

Smectic C ◽

Fluorescence Measurements ◽

Dichroic Dye ◽

Linearly Polarized

AbstractThe long-range orientational order of three members of 4-n-pentylphenylthio-4′-n-alkoxybenzoate $$ (\bar nS5) $$ series doped with a dichroic dye was studied by means of electronic absorption and fluorescence measurements. The order parameters <P2> and <P4> as well as the orientational distribution function were determined on the basis of absorption and emission spectra of linearly polarized light recorded as a function of temperature in the nematic, smectic A, and smectic C phases. An influence of the dye molecular structure on the orientational order of the dye/liquid crystal mixture was observed. Moreover, the dependence of the order parameter values on the length of the alkoxy chain in liquid crystal molecules was found. It was shown that the order parameter <P4>, obtained from fluorescence measurements, can be helpful in recognizing the second-order or weakly first-order transitions between various liquid crystalline phases.

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