We discussed the effect of polymer concentration and localization on flexoelectro-optical device using short pitch cholesterics oriented in uniform lying helix texture. By using a small concentration of photoreactive liquid crystal monomer with various concentrations and selecting the illumination conditions, we have been able to create a localized polymeric network at both substrate surfaces. We can stabilized the two switching modes and eliminating at the same time the effect of the residual birefringence of the polymeric network in the field-unwound state of the sample. The device has two operating modes: amplitude and phase modulation mode, respectively. The amplitude modulation mode is a fast in-plane switching of the device optic axis that enables to achieve a 100 % modulation of the transmitted light intensity whereas the phase mode gives a continuous change of the refractive index and thus of the phase shift of the transmitted light.

Date Published: 12 April 2005
PDF: 8 pages
Proc. SPIE 5741, Emerging Liquid Crystal Technologies, (12 April 2005); doi: 10.1117/12.584499

Published in SPIE Proceedings Vol. 5741:
Emerging Liquid Crystal Technologies
Liang-Chy Chien, Editor(s)