DETERMINATION OF VISCOELASTIC COEFFICIENTS FROM THE OPTICAL-TRANSMISSION OF A PLANAR LIQUID-CRYSTAL CELL WITH LOW-FREQUENCY MODULATED VOLTAGE

Citation
H. Schmiedel et al., DETERMINATION OF VISCOELASTIC COEFFICIENTS FROM THE OPTICAL-TRANSMISSION OF A PLANAR LIQUID-CRYSTAL CELL WITH LOW-FREQUENCY MODULATED VOLTAGE, Journal of applied physics, 74(10), 1993, pp. 6053-6057
Citations number
12
Categorie Soggetti
Physics, Applied
Journal title
ISSN journal
00218979
Volume
74
Issue
10
Year of publication
1993
Pages
6053 - 6057
Database
ISI
SICI code
0021-8979(1993)74:10<6053:DOVCFT>2.0.ZU;2-3
Abstract
The viscoelastic response of the nematic director field to low-frequen cy modulations of the driving voltage was studied by means of optical transmission measurements. An external ac voltage above the critical f ield U(c) was weakly amplitude modulated with frequencies in the range of 1 to 100 Hz. The viscosity coefficients alpha1, gamma1, gamma2, an d eta(b) influence the time dependence of the director field. They wer e determined by fitting the phase and amplitude of theoretically calcu lated optical transmission curves to measured data.