91Ó°ÊÓ

The cholesteric liquid crystal phase, also known as the chiral nematic phase, differs from the nematic phase in its molecular arrangement, optical properties, and response to external stimuli. In the cholesteric phase, the director rotates around an axis perpendicular to it, creating a helical structure, while the nematic phase has molecules aligned parallel to the director. Cholesteric liquid crystals selectively reflect certain wavelengths of light due to their helical structure, resulting in vivid colors under polarized light, whereas nematic liquid crystals display optical anisotropy but no unique optical properties related to structure. Moreover, the response of cholesteric liquid crystals to external stimuli is more gradual and complex due to the helical structure, making them suitable for temperature-sensitive or tunable optical devices, whereas in the nematic phase, molecules are easily reoriented by external fields such as electric or magnetic fields, used in LCDs.