Flexible Reflective Display Based on Cholesteric Liquid Crystals

Encapsulated cholesteric liquid crystals (CLCs) are used to build flexible reflective CLC displays. The encapsulation will prevent the inter-regional diffusion and thus also plays the role of the partition. Bistable reflective CLC displays can be switched from one state to another by external stimuli. This chapter discusses the transitions between cholesteric states induced by externally applied voltages. It considers a CLC with a positive dielectric anisotropy. Bistable CLC reflective displays have the merits of bistability, good color performance, roll-to-roll fabricating capability, and multiple writing methods (electrical, thermal, physical, and optical addressing methods). They have many applications such as e-reader, writing board, and e-wallpaper. The chapter discusses the research and development activities in the last few years, especially in ITRI. In order to design a driving scheme for the bistable CLC display, its response to voltage pulses must be studied.