Dynamics of Electrically Driven Cholesteric Liquid Crystals by Triboelectrification and Their Application in Self-Powered Information Securing and Vision Correcting

Smart glass technology is rapidly evolving and finding significant application in light selectivity devices. However, a major disadvantage of such devices is their high energy requirement which hinders the commercialization progress. In this work, a self-powered optical switch is developed based on the electrochromic effect induced by a vertical contact-separation triboelectric nanogenerator (VCS-TENG) in a cholesteric liquid crystal (CLC) display. The voltage produced by the VCS-TENG causes the CLC display to transition across different physical states, viz., planar, focal conic, and homeotropic, which correspond to varying opacities and applications. Light penetration testing showed that the proposed CLC achieved a shading rate as high as 80%. Moreover, our device demonstrated high durability of up to 500 cycles. Most of all, the novel device successfully implemented reliable performance in important applications that have been demonstrated in this work, including webcam and cellphone security, and occlusion therapy devices in ophthalmology.