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Opto-Electronics Review

Editor-in-Chief: Jaroszewicz, Leszek

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Volume 20, Issue 3


Measurement of elastic constants of nematic liquid crystals with use of hybrid in-plane-switched cell

E. Nowinowski-Kruszelnicki / J. Kędzierski / Z. Raszewski / L. Jaroszewicz / M. Kojdecki / W. Piecek / P. Perkowski / M. Olifierczuk / E. Miszczyk / K. Ogrodnik / P. Morawiak
Published Online: 2012-07-04 | DOI: https://doi.org/10.2478/s11772-012-0027-9


A new method for quick and pretty accurate measurements of splay, twist and bend elastic constants of nematic liquid crystals is experimentally verified. The main concept relies on exploiting only the electric field and determining magnitudes of nematic elastic constants from threshold fields for Freedericksz transitions in only one hybrid in-plane-switched cell. In such cell the deformations of an investigated liquid crystal are controlled by three separated pairs of electrodes confining measurement domains. In two of them inter-digital electrodes are mounted on one cell cover. Splay, twist and bend elastic constants can be measured by a proper choice of electrodes’ configuration together with orienting cover coatings (without applying magnetic fields). In this paper, we describe layout of our cells and results of experimental tests by using different liquid crystals: 5CB and 6CHBT (with positive dielectric anisotropy), Demus’ esters (with negative dielectric anisotropy) and new liquid crystals mixtures produced in our university.

Keywords: nematic liquid crystals; LC cell; elastic constants

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About the article

Published Online: 2012-07-04

Published in Print: 2012-09-01

Citation Information: Opto-Electronics Review, Volume 20, Issue 3, Pages 255–259, ISSN (Online) 1896-3757, DOI: https://doi.org/10.2478/s11772-012-0027-9.

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© 2012 SEP, Warsaw. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. BY-NC-ND 3.0

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