| abstract |
A directly addressable display device comprising at least one pixel cell (1-9), each pixel cell (1-9) being arranged for displaying a symbol, which symbol is repeatedly switchable between an on-state and an off-state, wherein each pixel cell (1-9) comprises an electrochromic layer (110) comprising an electrochromic and electrochemically active organic polymer material being electrochemically switchable between two different visually detectable coloring states; a counter electrode layer (140) comprising an electronically conductive material, wherein said counter electrode layer (140) in the viewing direction of the display device is arranged behind said electrochromic layer (110); an electrolyte layer (130), which electrolyte layer (130) is solid and arranged spatially between, and in ionic contact with, said electrochromic layer (110) and said counter electrode layer (140); a symbol defining layer (120) which is electronically and ionically insulating, arranged in direct ionic contact with said electrochromic layer (110), and which comprises one or more openings (121-129) which encloses said electrolyte layer (130) and defines the shape of said symbols; wherein said electrolyte layer (130) comprises a composition comprising a polyelectrolyte selected from one or more cationic polymers, wherein the electrolyte is substantially free of small cations. |