A tunable light scattering device fabricated using pseudopeptide polymer incorporated chiral nematic liquid crystal

Abstract

An increasing demand for innovative light manipulation technology results in an increased requirement for tunable light-scattering devices. In this work, we have fabricated a light-scattering device using chiral nematic liquid crystal (CLC) incorporated with a pseudopeptide polymer. The pseudopeptide polymer forms micron-sized balls in the E7 and CB15-based chiral nematic liquid crystal nonsolvent. This methodology provides a straightforward approach for manufacturing tunable light-scattering devices utilizing polymer ball-filled liquid crystals (PFLCs) without relying on conventional thermal or UV-curable processes. Experimental results demonstrate that the polymer ball enhances the light-scattering properties of the focal conic state of the chiral nematic liquid crystal, and the light-scattering properties can be tuned electrically. The 10 wt% polymer LC cell in the focal conic state reduces the direct light transmission in the visible region twice as compared to the non-polymer CLC. The inclusion of the polymer decreases the minimum voltage needed to induce the scattering state in the liquid crystal cell. The time required to initiate the scattering state in the CLC is also improved by the inclusion of the pseudopeptide polymer. Electrically tunable light scattering properties enable the application of this device in smart windows and tunable light diffusers.