Display Tech To Watch This Year: E-paper Stretches Its Wings
Electrowetting technology sandwiches the display media between a top and bottom layer of glass, while electrophoretic technology simply uses a polymer layer on top. That means that e-paper displays based on electrowetting designs will be thicker. But the technology also will allow manufacturers to build e-paper displays more cost-effectively by using existing LCD fabrication facilities with only relatively minor modifications.
As with electrophoretic technology, e-paper displays built using Liquavista's technology could be manufactured on a flexible plastic substrate, making them thinner and lighter. According to Demuynck, most returned e-reader products come back because the display glass gets broken. So the company is partnering with Plastic Logic, which is developing a display substrate that embeds the TFT array on an organic, plastic backplane. A commercial implementation, however, is still three to four years away, according to Plastic Logic.
With its acquisition by Samsung, Liquavista has refocused. Johan Feenstra, the founder and former CTO of Liquavista, has been named CEO, and Liquavista now has the resources to produce, says Hildebrand. "If [Samsung] feels that it can be done within a year or two, there will be an enormous push for electrowetting. If they feel it can't be done, they will kill it. It will be a very good proving ground for the technology," he adds.
Flex it, curve it, fold it
The next innovation will be flexible e-paper displays. Unlike LCDs, which manufacturers build on a rigid glass substrate using a discrete, one-at-a-time manufacturing process, e-paper displays can be literally printed onto a range of surfaces -- including glass, plastic, fabric, metal foil or even paper -- using a potentially less expensive, but still unproven, "roll-to-roll" manufacturing technique. A substrate made from plastic or another nonrigid material allows manufacturers to create flexible displays.
While today's e-reader displays are built on plastic, they're housed in a rigid enclosure, and the focus is on other benefits of plastic, such as its durability, thinner size and lighter weight compared with glass. Colegrove expects that to change. "Within 12 months, the consumer will be able to purchase flexible active-matrix e-paper displays," she predicts.
Eventually, the screens may lead to truly flexible product designs that can be rolled up, but early attempts are focused on creating contoured display surfaces. LG Display, for instance, recently demonstrated a prototype 19-in. flexible e-paper display that can be gently flexed without a degradation of image quality.
E Ink already offers flexible displays in its small, low-resolution product lines, such as wristwatches. "Our imaging films are intrinsically flexible," says Peruvemba. The next step will be to create the same capabilities for use in the larger, higher-resolution screens used in e-book readers.
Peruvemba says E Ink has helped about a dozen manufacturers of e-readers and other devices create flexible backplanes for use with its flexible display. "In the next several months, we anticipate that our customers will commercialize high-resolution displays that are flexible," he says.
In the meantime
Rigid e-readers will continue to be the norm for the time being -- the first with flexible displays won't appear before 2012 or 2013, says Hildebrand. This year, he says, "we will see some color devices, and we will see a lot of different products that try to cross the border between tablets and e-book readers."
And look for a slew of new, low-priced e-readers from Chinese manufacturers in time for the 2011 holiday season. "You'll see some very low-cost devices that Wal-Mart or someone will have for 60 bucks," he says.