High contrast-ratio cholesteric liquid crystal reflective display based on lying helix structure

This study explores the formation of the lying helix (LH) structure in cholesteric liquid crystal (CLC) systems under low-frequency voltage driving and its application in reflective displays. Induced by electrohydrodynamic effects, the LH structure exhibits significantly reduced reflectance compared to the conventional focal conic state, resulting in enhanced contrast for reflective displays. At 20 V, the LH state achieves a reflectance of less than 1% while maintaining a bright-state reflectance of over 30%, yielding a contrast ratio exceeding 30. The influence of driving voltage, frequency, and temperature on LH formation is systematically investigated, emphasizing the critical role of controlled disturbance intensity in achieving optimal LH alignment. Practical demonstrations with full-color CLC panels validate the advantages of the LH structure, including deeper blacks, enhanced brightness, and improved color saturation. These findings underscore the potential of the LH structure to advance high-quality, energy-efficient reflective display technologies.