Imaging liquid crystal defects

Polymer stabilization is used to image the director fields of a range of different s = +/- 1 and s = +/- 1/2 Schlieren and umbilical defects in nematic liquid crystals, such as radial, vortex and swirl defects of strength s = +1. We demonstrate experimentally the director field around such defects and show that they coincide with schematic representations commonly found in literature. The proposed method can be used non-invasively or invasively, depending on the resolution required.