“Molecular Engineering of Materials: Effect at Interfaces and in the Bulk of Liquid Crystals”
Dr. Devanand K. Shenoy, Research Physicist
Center for Bio/Molecular Science and Engineering
Naval Research Laboratory
Washington DC 20375
Room #303, EE/CSE Building
October 30, 2002
Surface interactions play a central role in the behavior of liquid crystals in thin cells. Photo-alignment methods are a relatively new approach to control of liquid crystal orientation at solid surfaces and therefore in the bulk. We have recently developed a photo-dimerized monolayer that has been shown to function as an alignment layer for nematic liquid crystals. Moreover, chemical modification of the monolayer allows for control of the polar anchoring energy and pre-tilt of liquid crystal molecules. We have also evaluated display relevant properties such as contrast, voltage holding ratio and response times. An overview of the results obtained in this project will be presented. The second part of the talk will focus on recent results in ferroelectric liquid crystal materials for uncooled IR sensors (for example, night vision cameras). In particular, new phenomena that have been observed and interpreted will be presented.