A Viewing Angle Switching Panel Using Guest–Host Liquid Crystal

We have numerically and experimentally investigated an optical device based on a guest–host (GH) liquid crystal (LC) for a viewing angle switching (VAS) application. This device should work as an additional panel, mounted on a major panel of conventional liquid crystal display, to implement the VAS operation. Our proposed method employs the composite effect of the GH-LC mixture, which is identified as the combination of the guest-induced absorption effect and the host-induced birefringence effect. The benefit of this composite effect is that the viewing angle can be controlled by not only the transmittance-reduction mechanism but also the contrast-ratio-reduction mechanism. The performance of this VAS panel is first predicted by the analytical calculations, and then confirmed by the experimental results.