The introduction of teaching about liquid crystals is discussed from several points of view: the rationale why to teach them, the basics about liquid crystals or what the teacher should teach about them, the fundamental pre-knowledge of students required, the set of experiments accompanying the teaching and the brief report on the already performed testing of the teaching module.
COBISS.SI-ID: 9454409
Anisotropy is a difficult concept, although it is often met in everyday life. This paper describes a simple model—knitted patterns—having anisotropic elastic properties. The elastic constant is measured for the force applied in different directions with respect to the knitting direction. It is also shown that the deformation of the knitted pattern does not always have the same direction as the applied force, a behaviour that is also typical for anisotropic systems. The dependence of the elastic coefficient on the direction of applied force has the same form as the refraction coefficient of an extraordinary ray in a uniaxial anisotropic crystal.
COBISS.SI-ID: 9350729
The two-dimensional presentation of the three-dimensional nematic liquid crystal structure can be visualized in various ways: by oriented rotational ellipsoids, bricks, cylinders, or sticks, representing either individual molecules or nematic director field. Here, we give a different approach: the three axes of Cartesian coordinate system are assigned with three colors (red for x-axis, green for y-axis and blue for z-axis). We use the proportional mixing of these colors for various directions of the nematic director. Using this technique, different structures of nematic liquid crystals can be visualized clearly, particularly when combined with representation of nematic director field with sticks.
COBISS.SI-ID: 18901000