Encapsulation approaches in advanced display technology

Electronic paper, also called e-paper, is a display technology designed to mimic the appearance of ordinary ink on paper. Unlike a conventional flat panel display, which uses a backlight to illuminate its pixels, electronic paper reflects light like ordinary paper and is capable of holding text and images, allowing the image to be changed later. The most representative examples of electronic paper are the technologies, introduced in the beginning of 2000, by the corporations E-INK and Gyricon. Common point of the developed technologies is the use of microencapsulated, electrically polarized particles. Examples of commercial electrophoretic displays include the high-resolution active matrix displays used in the Amazon Kindle, Sony Librie, Sony Reader, and iRex iLiad e-readers. These displays are constructed from an electrophoretic imaging film manufactured by E Ink Corporation. The main limitations of the E-INK and Gyricon approaches are the reduced application fields and the bichromality which could only overcomed employing color filters. With the aim of getting over the intrinsic limitation of the today's existing technologies, Fraunhofer Gesellschaft researchers in collaboration with the University of California Riverside (UCR) developed a technology based on microencapsulated colloidal photonic crystals. Characteristics of the encapsulated system are its memory effect and the not-required insertion in electronic circuit thus leading to broad applicability. The E-Ink and Gyricon systems will be described together with forthcoming technologies developed by researcher at the Fraunhofer Gesellschaft and UCR. (Abstract = vollständige Veröffentlichung)