A process for fabricating flexible reflective display devices using a composite film of ferroelectric liquid crystal and polymer

We have developed a process for fabricating flexible reflective display devices using thin composite films of aligned polymer-monostabilized ferroelectric liquid crystals encased between plastic substrates. In order to precisely control the thickness of these films, photolithography is used to fabricate spacer posts on a substrate, and a printing technique that can form a liquid crystal/monomer solution film on the substrate uniformly. Control voltages are applied to the layer via transparent electrodes; in order to prevent a short circuit between these electrodes, an insulator layer is also formed on the other substrate. Once the two substrates are attached to one another, polymer walls and fibers are created in the liquid crystal layer between the two substrates by photopolymerization-induced phase separation which was induced by two-step exposure of ultraviolet light. A fabricated device is sandwiched between a polarizer and a diffuse mirror to make a reflective display. Uniform display operation was obtained when the device was driven with a voltage, even when the device was bent with a 5-cm radius of curvature.