J. Phys. II France
Volume 6, Numéro 12, December 1996
Page(s) 1663 - 1668
DOI: 10.1051/jp2:1996155
J. Phys. II France 6 (1996) 1663-1668

A New Method of Viscosity Determination from the Electro-Optical Response of a Nematic LCD

O. Cossalter, B. Cramer and D.A. Mlynski

University of Karlsruhe, Institut für Theoretische Elektrotechnik und Me$\ss$technik, Kaiserstr. 12, 76128 Karlsruhe, Germany

(Received 7 May 1996, revised 9 August 1996, accepted 14 October 1996)

We determine viscosity values of ZLI-2293 (Merck), to our knowledge for the first time, from a measured transmission versus time curve of a TN-cell with the "optical bounce" [1, 2]. Our method combines the measurement of this transmission curve with the simulation of the corresponding director field and a suitable optimization process using Simulated Annealing [3] to obtain the viscosities. The advantage of our approach is the small experimental expense compared to that of a direct viscosimetric measurement while achieving nearly the accuracy of the direct method.

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