Printed Polymer-Stabilized Chiral Nematic Liquid Crystal Privacy Windows

Abstract

In this paper, drop-on-demand (DoD) printing is demonstrated of polymer stabilized chiral nematic liquid crystal (PSCLC) privacy windows that can function in either a conventional mode (scattering to transparent) or reverse mode (transparent to scattering) with the application of an electric field. Inkjet printed droplets of the PSCLC mixture, with diameters of the order of 100–200 µm and sandwiched in LC layer thicknesses of ≈10–15 µm, are characterized in terms of their transmission as a function of the electric field amplitude and the response times for switching into and out of the scattering state. The results show that the printed droplets, and arrays thereof, exhibit similar electro-optical properties to analogous thin-film devices, but with the ability to incorporate bespoke features such as images and decorative patterns. Finally, the electro-optical switching of a printed PSCLC privacy window whereby alphanumeric characters can be made to appear and disappear with the application of an electric field is demonstrated.