Plasmonic color originating from metallic nanostructures has many advantages over traditional pigmentation based color and have demonstrated sub wavelength resolution, tolerance to high intensity light, and scalability of the structure's optical response with dimensions and surrounding media. The later of these attributes, post-fabrication tunability, is a unique advantage of plasmonic structures that may enable it to reach niche applications. However, previous attempts of plasmonic tuning have yet to span an entire color space with a single nanostructure dimension. Here, we demonstrate a full red-green-blue (RGB) color changing surface enabled by a high birefringent liquid crystal (LC) and with a single nanostructure. This is achieved through the onset of a surface roughness induced polarization dependence and a combination of bulk and surface LC effects which manifest at different voltages. To further show the feasibility of such a system for display applications, we integrate the LC-plasmonic device with an actively addressed thin film transistor array (TFT) to display arbitrary images and video. Such a color changing surface may also find applications in wearables and active camouflage.
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