Hybrid-aligned nematic

Fig. 7.15. The vertically aligned nematic-hybrid aligned nematic (VAN-HAN) zenithal bistable device geometry. The homeotropic state (left) is black while the hybrid state (right) is bright.

C.-W. Kuo, S.-C. Jeng, H.-L. Wang, C-.C. Liao, Application of nanoparticle-induced vertical alignment in hybrid-aligned nematic liquid crystal cell. Appl. Phys. Lett. 91, 141103 (2007)... 

Two sets of chiral-nematic hybrid are chemically bonded to the same dithienylethene core as for the photoswitchable nematic GLC (30), resulting in a smectic C -cholesteric GLC as depicted in Fig. 6.10. A sample of (31) was placed between two alignment-coated fused silica substrates for heating to 230 °C followed by cooling to 207 °C, where shearing was applied to induce alignment. The... 

It has also been used to study the second sound resonance in smectic A liquid crystals and measure the compression modulus. For measuring the flexocoefficients (ei — 63) and (ei + 63), hybrid-aligned nematic cells have been used extensively. AC techniques avoid problems associated with ionic impurities, but require elaborate numerical fitting of the data. Some observations on the pnblished measurements of flexo-coefHcients are made in Section 2.4, which ends with a few concluding remarks. 

Fig. 2.2. Schematic diagram of a hybrid-aligned nematic cell. The field-free director (shown by the continuous curved line) has a splay-bend curvature distortion in the xz plane. A DC field applied along the y axis rotates the polarization and the director (shown by the curved dashed line) acquires a 4>(z) profile. (Reproduced from Dozov et al. with the permission of EDP Sciences, http //publications.edpsciences.org.)...

N.V. Madhusudana and G. Durand, Linear flexo-electro-optic effect in a hybrid aligned nematic liquid crystal cell, J. Physique Lett. 46(5), L-195-L-200, (1985). doi 10.1051/jphyslet 01985004605019500... 

N.T. Kirkman, T. Stirner and W.E. Hagston, Continuum modelling of hybrid-aligned nematic liquid crystal cells optical response and flexoelectricity-induced voltage shift, Liq. Cryst. 30(9), 1115-1122, (2003). doi 10.1080/02678290310001594562... 

S.A. Jewell and J.R. Sambles, Fully leaky guided mode study of the flexoelectric effect and surface polarization in hybrid aligned nematic cells, J. Appl. Phys. 92(1), 19-24, (2002). doi 10.1063/1.1483392... 

T.S. Taphouse, S.L. Cornford, J.E. Birkett and J.R. Sambles, Time-resolved sign-dependent switching in a hybrid aligned nematic liquid crystal cell. New J. Phys. 10(8), 083045/1-15, (2008). 

P.R. Maheswara Murthy, V.A. Raghunathan and N.V. Madhusudana, An AC electro-optic technique of comparing the two anchoring energies of a hybrid aligned nematic cell, Liq. Cryst. 14(4), 1107-1124, (1993). 

Flexoelectric patterns also exist for nematic layers with asjrmmetric boundary conditions, i.e. with homeotropic anchoring on one surface and planar anchoring on the other one hybrid-aligned nematics).The critical voltage and the critical wave number obtained with the one-elastic-constant approximation are in a good agreement with experimental re-sults. ... 

Zenithal bistable devices have been used in several types of electro-optic geometry. In the VAN-HAN mode, Fig. 7.15, one ZBD surface is combined with a fiat homeotropic surface. In the planar ZBD state (Fig. 7.15 right), the nematic is hybrid aligned with the director plane rotated 45° with... 

A. Mazzulla, F. Ciuchi and J.R. Sambles, Optical determination of flexoelectric coefficients and surface polarization in a hybrid aligned nematic cell, Phys. Rev. E 64(2), 021708/1-6, (2001). doi 10.1103/PhysRevE.64.021708... 

Bent-core liquid crystalline elastomer Bent-core nematic swollen in a liquid crystal elastomer Black lipid membranes Direct current Electroconvection Electrohydrodynamic Ferroelectric liquid crystal Hybrid-aligned nematic Human embryonic kidney Isotropic... 

After the successful demonstration of the practical utilization of hybrid aligned and photopolymeiized discotic nematic films in commercial LCDs, Fuji photo film... 

Y. Lu, X. Liang, Y. H. Wu, et al.. Dual-frequency addressed hybrid-aligned nematic liquid crystal, Appl Phys. Lett. 85, 3354 (2004). 

T. Uesaka, E. Yoda, T. Ogasawara, and T. Toyooka, Optieal design for wide-viewing-angfe transflective TFT-LCDs with hybrid aligned nematic compensator, Proc. 9th Int L Display Workshops, pp. 417-420 (2002). 

S. H. Lee, K. H. Park, J. S. Gwag, et al., A multimode-type transfleetive liquid crystal display using the hybrid-aligned nematic and parallel-mbbed vertically aUgned modes, Jpn. J. Appl. Phys., part 1, 42, 5127 (2003). 

Hybrid Aligned Nematics, Appl. Phys. Lett. (19S2) 162... 

Enhanced nonlinear birefringence in hybrid aligned nematics... 

FIG. 1. Schematic representation of the hybrid aligned nematic (HAN) cell with no applied field. The rod lines show the alignment of the director n at different points in the cell. 

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