Teaching Liquid Crystals with a Wood Model

The uniaxial symmetry in the liquid crystalline phase leads to anisotropy in many physical properties. A simple look on a piece of wood reveals that also its structure is anisotropic. It has also strong anisotropic dielectric properties in the microwave range, like liquid crystals in the visible range. Therefore the wood can serve as a model for demonstration of anisotropic optical properties in liquid crystals. Experiments for more illustrative explanation of the anisotropic properties are presented. As wood is transparent for microwaves, many anisotropic properties can be illustrated experimentally, using a simple school microwave kit.