E Ink is an electronic device that is similar to a computer display, but with qualities that enable it to be used for applications such as eBooks, electronic newspapers, portable signs, and foldable, rollable displays. E Ink Corp. (a Cambridge, Massachusetts company) and Lucent are developing the device, which combines E Ink's electronic ink with Lucent's flexible transistors. Prototypes have featured 25-inch display areas involving several hundred pixels. Although the new technology's more complex applications - such as electronic newspapers and improved e-books that are very similar to traditional books - are likely still at least 10 years in the future, E Ink is currently being tried for simpler applications, such as retail signage.
The E Ink prototypes combine thin, plastic transistors with polymer LEDs (light-emitting diodes) to create what are called smart pixels. The process involved - which is not dissimilar to traditional printing processes - uses silicon rubber stamps to actually print tiny computer circuits onto the surface. The electronic ink used is a liquid substance consisting of millions of tiny capsules floating in a substance like vegetable oil. The capsules, which are filled with a dark dye, contain negatively charged white chips that move either up or down within the capsules in response to a positive charge applied to the medium's surface. Information to be displayed is downloaded through a connection to a computer or a cell phone, or created with mechanical tools such as an electronic "pencil," and remains fixed until another charge is applied to change it. The devices use very low power: according to a spokesperson, prototypes of the device have been running on watch batteries.
Xerox, in partnership with 3M is working on a competing technology, called Gyricon.