The aim of this book is to describe the recent progress in our understanding of the surface and interface properties of the substrate-liquid crystal interface that play an essential role in the operation of liquid crystal displays (LCD?s) and other LC devices. Every LC electro-optic device is based on the controllable anchoring of LC molecules on a (polymer coated) solid.

The microscopic understanding of the interaction between a macromolecule (liquid crystal, polymer) and a wall is also a major scientific problem that, despite its technological importance and thirty years of research, is still poorly understood. The main reason for this was the lack of surface sensitive techniques that could probe interfaces at the proper molecular level. Therefore most attention was directed to understand the bulk properties whereas interface properties were only addressed by macroscopic, empirical studies like wetting and spreading.
In 1998 we started a collaborative effort between several European Laboratories to study the liquid crystal interfaces with novel, surface and interface-sensitive experimental techniques, such as Atomic Force Microscopy (AFM), Scanning Tunneling Microscopy (STM), Linear and Nonlinear Optical Microscopy and (Dynamic) Light Scattering (DLS). These experimental techniques were complemented with computer simulations and supra molecular chemistry methods to develop controllable polymeric surfaces.
The main goals of the project were:
1. to obtain a microscopic understanding of the liquid crystal-wall interactions on a molecular level.
2. to understand how these interface properties can determine the long range ordering and properties of LC devices.
3. to study how this understanding can be exploited to manipulate the relevant interface properties, in order to control LC-based devices.

After 5 years we can state that we more than fulfilled our original goals. In particular the development of the Scanning Probe methods and the parallel progress in theory have largely contributed to our deeper understanding of the liquid crystal wall interactions on a molecular level. The present book will try to give an overview of the state of the art of our understanding of the liquid crystal-surface interactions on a molecular level.

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