Image quality enhancement of transparent waveguide display using a twisted nematic mode polymer-stabilized liquid crystal

In this study, a twisted nematic mode polymer-stabilized liquid crystal (TN mode PSLC) integrated with a crossed polarizer was used to create a transparent waveguide display. When a voltage was applied, the PSLC scattered the waveguide light with a high polarization selectivity such that no substantial loss of the outgoing light intensity was observed after integrating the polarizer. However, with a crossed polarizer, in the ON state, the background light was not only scattered but also absorbed by the analyzer. Using this device configuration, with a 12 μm cell gap and 7% monomer concentration, we successfully realized a normally transparent waveguide display. The contrast ratio of the waveguide outgoing light was 26 and that of the undesired background reached 90. This device can display images due to waveguide edge-lit light scattering and simultaneously block the background information to improve the image quality.