US Patent 7420549 Electro-wetting displays

The performance of electro-wetting displays can be improved by: (a) providing a concealment member (112) which conceals the moving fluid (108) when that fluid (108) is confined to a small area; (b) using the moving fluid to cover one or more sections of a filter or reflector having differently-colored sections; (c) moving the moving fluid between the rear surface and a side surface of a microcell; (d) using as a substrate for a moving fluid a substrate resistant to wetting by the fluid but pierced by multiple conductive vias capped with a material wetted by the fluid; and (e) coloring the moving fluid with pigments or nanoparticles.