Polymer Dispersed Liquid Crystals for Electronic Applications
The electrooptic characteristics of liquid crystal-polymer composites (PDLC, PNLC, NCAP...) are strongly dependent on surface interactions between polymer and liquid crystal molecules. In order to clarify this dependence, we have investigated the chemical modification of the surface of the polymer, without affecting its bulk properties. We show that it is possible to greatly modify the electrooptic performances of composite cells, and thus to optimise them for an application in visualisation.
KeywordsLiquid Crystal Electrooptic Property Liquid Crystal Molecule Phase Separation Process Polymer Disperse Liquid Crystal
Unable to display preview. Download preview PDF.
- 1.J.W. Doane, Liquid Crystals Applications and Uses, World Scientific, 1990, ch 14, p361.Google Scholar
- 2.E. Ginter, E. Lueder, T. Kallfass, S. Huttelmaier, M. Doblcr, V. Hochholzcr, D. Coates, M. Tillin, P. Nollan, “Optimized PDLCs for active-matrix addressed light valves in projection systems”, Proc. 13th IDRC, 1993, pl05.Google Scholar
- 3.H. Yoshida, K. Nakamura, H. Tsuda, M. Ohashi, I. Tomita, M. Okabe, “A direct view polymer-dispersed LCD with crossed Nicois and a uniaxial film”, Proc. 13th IDRC, 1993, p121.Google Scholar
- 7.H. Nomura, S. Suzuki, Y. Atarashi, “Interfacial interaction between nematic liquid crystal and polymer in composite film...”, JapJ. Appl.Phys., vol 30(2), p327, 1991.Google Scholar
- 9.L. Bouteiller, P. Le Barny, F. Massie, P. Robin, “Influence of the chemical nature of polymer surface on electrooptic properties of PNLC”, Proc. 13th IDRC, 1993, p325.Google Scholar
- 10.The swelling ratio measures the increase in volume of a piece of polymer immersed in a solvent. It is measured by weighing.Google Scholar
- 11.In ref 9, the polymer in cells modified for more than T do not recover their initial shape. This explains the dramatic increase of Tmin.Google Scholar