ping point for e-paper, but maintains the technology hasn’t yet come of age because consumers will eventually want video capabilities, bistable pixels (giving displays the ability to operate for long periods on very little or no power), thin or flexible designs, and, of course, vivid color. “No product or technology on the market is even close to offering this, including the FLEPia,” Heikenfeld says. “With our technology, we are aiming to provide the revolutionary increase in brightness that is not possible using the technologies currently available as a product.”

Heikenfeld’s electrofluidic display technology is based on a process called pigment dispersion. “The pigments look as good as they would on paper,” he says. The technology, which Heikenfeld calls a “major step forward” in color e-paper research, consists of an insulator film situated between the pigment dispersion and an electrode film. When voltage is applied to the electrode film, it creates an electrical force that can stretch the pigment dispersion. “We don’t mix the pigments,” he says. “We display them in different areas, on demand.” Obtaining red, for example, requires overlaying yellow and magenta. When the voltage is removed, the pigment dispersion bounces back to its favored geometry of a small droplet or bead shape.

“We have a lot of approaches under development that we have not published yet, so I can’t go into all the details,” Heikenfeld says.

Heikenfeld’s electrofluidic display technology is one of almost a dozen different technologies being developed to create low-power e-paper that can render colors as brilliantly as traditional paper can. Judging by recent developments in terms of display size and power consumption in e-readers coming to market, the future for e-paper technology appears bright. In 10 or 20 years, Heikenfeld says, consumers might see large e-paper modules that are as thin and as flexible as magazines are today, with display brightness approaching that of conventional print.

In Heikenfeld’s imagined future, these solar-powered devices will have touch interfaces, communication capabilities, and be so energy efficient that charging them will be an afterthought.

“You might click on an image in a story, and it will provide video or animation,” he says. “There is nothing fundamental from an optics or electronics perspective that makes this impossible.”

For his part, Sheridon believes e-paper eventually will make power-hungry desktop displays obsolete, and will help make heavy, back-breaking textbooks something school children might learn about in a history lesson on their lightweight e-readers, not lugged around with them in their backpacks. But when it comes to betting whether all paper books will become a thing of the past, the inventor of e-paper is cautious about predicting the obsolescence of the printed page. Sheridon simply suggests that in the future books might be printed on paper.

“E-paper will continue to find important applications, such as in fabric, large displays, and home and building decoration, to mention a few,” says Sheridon. “The surest way to predict the future is to invent it. E-paper is rich in potential.”

 

Further Reading

Feenstra, B. J.

Electrowetting Technology Aims To Improve on the Performance of LCDs for Mobile Applications, Information Display 22, 11, 2006, 10–13.

Green, A.M., Montbach, E., Miller, N., Davis, D., Khan, A., Schneider, T., Doance, J. W. Energy Efficient Flexible Reflex Displays, Proc. Int’l Display Research Conf., Society for Information Display, 2008, 55–58.

Heikenfeld, J., Zhou, K., Kreit, E., Raj, B., Yang, S., Sun, B., Milarcik, A., Clapp, L., Schwartz, R. Electrofluidic Displays Using Young-Laplace Transposition of Brilliant Pigment Dispersions, Nature Photonics 3, 5, 2009, 292–296. Lenssen, K.-M. H., Baesjou, P.J., Budzelaar, F.P.M., van Delden, M.H. W.M., Roosendaal, S.J., Stofmeel, L. W.G., Verschueren, A.R.M., van Glabbeek, J.J., Osenga, J. T.M., Schuurbiers, R.M. Novel Concept for Full-Color Electronic Paper, J. Society for Information Display 17, 4, 2009, 383–388. Sheridon, N. K. and Berkovitz, M. A. A Twisting Ball Display, Proc. Society for Information Display 18, 3/4, 1977, 289–293.

based in Los angeles, Kirk L. Kroeker is a freelance editor and writer specializing in science and technology.

© 2009 aCM 0001-0782/09/1100 $10.00

Belated
Apology
For Turing

British Prime Minister
gordon Brown apologized
for the British government’s
“horrifying” treatment 50
years ago of alan Turing,
the mathematical genius
and a founder of modern
computing, who was criminally
prosecuted and convicted of
“gross indecency” in 1952 after
admitting to a homosexual
experience. To avoid
imprisonment, he underwent
chemical castration. Two years
later Turing committed suicide
at the age of 41.
earlier this year, British
computer scientist and blogger
John graham-Cumming
launched an online petition
campaign urging the British
government to apologize. The
petition was supported by
scientist richard dawkins,
writer ian Mcewan, and
gay-rights activist Peter
Tatchell, and it received 31,612
signatures from British citizens
and residents before Brown
issued an apology.
graham-Cumming has also
written to Queen elizabeth ii,
asking that Turing be awarded
a posthumous knighthood.
in 1936, Turing wrote
his seminal paper, “on
Computable Numbers,” which
established the conceptual
and philosophical basis for
modern-day computers, and
consequently developed the
Turing Test, an important
measure of success in the
field of artificial intelligence.
during World War ii, Turing
developed the Bombe, an
electromechanical code-
breaking device that enabled
Britain to read secret messages
encoded by germany’s enigma
cipher machines, complex
typewriter-like devices that
generated a constantly
changing code for its military
communications.
aCM President dame
Wendy hall issued a statement
applauding Brown’s apology,
recognizing his computer
science and wartime
contributions, and noting that
“aCM looks forward to joining
with other organizations to
celebrate the centenary of
Turing’s birth in 2012.”