Course syllabus for Liquid crystals, physics and applications

Basic courses on Optics, Electromagnetics, Thermodynamics, Solid state physics

We aim to give a thorough introduction to the physics and applications of liquid crystals. In addition, we give an overview of the state-of-the art of the field, both within research and industry. We also aim to give the students training in experimental work, in which experiments are designed and carried out by the students themselves to find the solution to given questions. Through a large number of examples and demonstrations during lectures and laboratory excercises, we aim to stimulate the student to see the connections to other courses in and fields of science. The course gives a good basis for future advanced studies of liquid crystals but we hope that you will find the skills and knowledge gained from this course most rewarding, also for future activities within other disciplines.

- describe the structures, symmetries, and order of the most common liquid crystal phases 

- understand the basic electric, elastic, and optical properties of liquid crystal materials 

- explain the structure and function of liquid crystal displays and devices. 

- experimentally identify the most important liquid crystal phases 

- carry out basic optics and electrooptical measurements of liquid crystal properties 

- explain the main fabrication steps in liquid crystal display manufacturing 

- discuss questions and problems related to liquid crystal science and applications, and to propose solutions/draw sound conclusions by combining knowledge of optics, symmetries, thermodynamics, electromagnetism, condensed matter physics, and other relevant fields of science.

 Most people are familiar with the fact that matter can exist in three different states: solid, liquid and gas. However, this is a simplification, and under extreme conditions other forms of matter can exist, e.g. plasma at very high temperatures or superfluid helium at very low temperatures. But we do not have to go to these extreme conditions to find new forms of order in matter. In liquid crystals, which are anisotropic fluids, the molecular order lies between those of the isotropic liquid and the crystal and the classification of liquid crystals is based on their degrees of orientational and positional order. From a basic physics point of view these materials are of large interest and have contributed to the modern understanding of phase transitions and critical phenomena, and to the knowledge about order phenomena in one, two, and three dimensions. 

To common people liquid crystals are today almost synonomous to flat panel displays (Liquid Crystal Displays, LCDs) for TVs, computers, mobile phones, and other electronic equipment. But there is also a rapid development of other types of application, for instance in telecommunication, and photonics. Liquid crystalline structures are readily used as templates for synthesis of advanced porous materials and recently liquid crystal have also been proposed as matrices for positioning and aligning nanoparticles of different shapes, i.e. for new types of composite materials and metamaterials. 

Liquid crystals consitute a unique form of soft matter. The existence of life is directly dependent on self-organizing soft matter and here liquid crystalline systems play vital roles. One example is cell membranes which consist of so-called lyotropic liquid crystals. Another is DNA that under certain conditions form liquid crystals. Maybe the origin of the extremely long DNA molecule can be found in self organisation and liquid crystal formation of small molecules.

The course will give a basic understanding of the physics and different applications of liquid crystals. The content ranges from the history of liquid crystal science, from the first observations in the late nineteenth century, via the development of theories of the liquid crystalline state, the development of applications - especially liquid crystal displays - and examples of today's state of the art research. After decades of strong focus on liquid crystal displays, a large part of the liquid crystal research is today shifting towards nanoscience, biological systems and, on the applicational side, towards photonics and microwave electronics. 

The course will stress on, and illustrate, how knowledge in optics, thermodynamics, electromagnetism, vector analysis, symmetry analysis, etc. constitutes the basis for the still on-going development of liquid crystal displays and devices that we use every day. Furthermore, the course will through laboratory projects and demonstrations give an introduction to the manufacturing of liquid crystal displays. 

1. Physical properties of liquid crystals and basic theory Phases and phase transisions; anisotropic materials; symmetry aspects; optics; electrooptics of liquid crystals; ferro-, and antiferroelectric liquid crystals; examples of LCs in nanoscience, photonics and microwave electronics, overview of the research front. 

2. Liquid crystal applications LCDs, present and future displays, demonstrations, manufacturing of devices, non-display applications, thermochromics, kevlar

About 15 Lectures, defining the contents of the course 

Lab project on individually choosen topics, laboratory excercises and demonstrations, cleanroom processing demonstrations 

homework assignments

Copies of lecture notes.

S.T.Lagerwall, P.G.Rudquist, D.S.Hermann: "Liquid crystals", in Encyclopedia of optical Engineering, Marcel Dekker Inc. 2003) 

Collings&Hird: Introduction to Liquid Crystals, Taylor&Francis 1997 (Recommended); 

Also parts of: J. Prost, P.G. de Gennes: The physics of liquid crystals, Oxford 1993;

S.Chandrasekhar: Liquid Crystals, Cambridge 1976, second edition 1992; 

E.B. Priestley, P. Wojtowicz, P.Sheng: Introduction to Liquid Crystals, Plenum, NY 1975; 

D.Demus et al. (editors) Handbook of Liquid Crystals, Volume 1-3, Wiley VCH, 1998;

 S.T.Lagerwall: Ferroelectric and Antiferroelectric Liquid Crystals, Wiley VCH 1999.

Lab project, home assignments, written exam, weighted as follows in the grading:

Written exam 70%

Lab project 15%

Home assignment 15%