Flexible thermochromic displays

Abstract

Large area flexible displays have many applications in information displays, decorative elements, and adaptive camouflage. Reflective displays, which change the actual surface color, have some advantages over emissive displays: they do not need the energy to emit light, they adapt automatically to the ambient lighting, and have a broad spectrum. Thermochromic materials can be used to implement flexible large-area low-resolution displays. We have demonstrated a reflective thermochromic display structure with 5cm x 5cm pixels fabricated on a thin Kapton foil using screen-printed heating elements, spray-coated thermochromic paint layers with controlled layer thicknesses, and copper traces for power delivery. The total thickness of the surface is under 200 μm.