Cholesteric Liquid Crystals with a Broad Light Reflection Band

Abstract The cholesteric‐liquid‐crystalline structure, which concerns the organization of chromatin, collagen, chitin, or cellulose, is omnipresent in living matter. In technology, it is found in temperature and pressure sensors, supertwisted nematic liquid crystal displays, optical filters, reflective devices, or cosmetics. A cholesteric liquid crystal reflects light because of its helical structure. The reflection is selective – the bandwidth is limited to a few tens of nanometers and the reflectance is equal to at most 50% for unpolarized incident light, which is a consequence of the polarization‐selectivity rule. These limits must be exceeded for innovative applications like polarizer‐free reflective…