If computer screens were as lightweight and flexible as a sheet of paper, your
newspaper could update you every hour and still be portable. As this ScienCentral
News video reports, some nanotechnologists say that soon everyone could be
reading off electronic paper.
One of nanotechnology's visions is a newspaper that updates itself constantly,
and fits in your pocket. Electronic paper would offer all the pluses of old-fashioned
newsprint: excellent resolution, high contrast that can be read in strong
or dim light, no need for external power to maintain an image. It would be
light and flexible enough to carry easily on your morning commute. But unlike
newsprint, electronic paper would spare trees and wouldn't leave any
messy newsprint on your fingers.
Such a dream will require computer screens as thin and supple as paper. Now
E Ink, a company in Cambridge,
Massachusetts, has announced a big step forward: an
ultra-slim computer display that bends and rolls up into a narrow tube,
about one inch in diameter.
The flexible display is a prototype of E Ink's ultimate goal, what the
company calls "RadioPaperô." Chemist Michael
McCreary, vice president for research and advanced development, believes
that RadioPaperô, or digital paper as it's also called, is going
"to revolutionize the publishing industry," because it's
so easily updated.
A key component of RadioPaperô is electronic
ink, invented by one of E Ink's cofounders, physicist Joseph
Jacobson, and his research team at the
Institute of Technology's Media Lab. This ink can be controlled
electronically, stays as sharp as regular ink, and doesn't require extra
power to retain text or images. Electronic ink consists of tiny capsules full
of minute particles of black and white pigment that is sensitive to electrical
charges. With a negative charge, white particles move to a capsule's
surface; with a positive charge, black particles move up, to form words and
pictures. With no charge, the pigment stays in place, so that text or graphics
E Ink's first commercial product was electronic signs for use in stores
and other public places. E Ink's signs used electronic ink to change
their messages every few seconds via wireless connections, eliminating
the need to constantly paste up new printed notices.
The company's most recent research has been
to "write" with electronic ink on a high-resolution flexible computer
screen. E Ink's new research prototype is little larger than a business
card, and no thicker than three sheets of paper. It can be rolled up into
a cylinder without distorting words or pictures. The secret of its slimness
and flexibility is very thin stainless steel foil. Traditional computer screens
are backed by inflexible glass covered with silicon transistors. Plastic can
be flexible, but may melt in the high temperatures required to fabricate transistors.
McCreary's team discovered that unlike plastic, thin metal foil could
withstand heat while remaining flexible.
"One of the advantages of RadioPaperô as we envision it,"
McCreary explains, "is that you could download many kinds of information
onto it, wirelessly or through an Internet connection." He foresees
pocket-sized electronic books that tell a different tale every week, smart
cards that let you know your credit balance or your train fare, and even wearable
Early next year, E Ink displays will be used to make electronic
books, a new way to read changing content on a display that looks very
similar to paper. The researchers' next steps toward electronic newspapers
including making the display thin enough to be folded, improving the ink's
switching speed, and adding color.
McCreary et al's research was published in Nature,
May 8, 2003, and is funded by E Ink.