31 July 2002

Pinto's Point: The future of paper

By Jim Pinto

Mankind has always sought to improve ways of communicating and recording thoughts. Early attempts at achieving this involved the use of waxed boards, leaves, bronze, silk, and clay tablets. It wasn't until the invention of paper that people shared information in high quantity and passed it on cheaply.

As far back as 4000 B.C., ancient Egyptians invented the first substance like paper as we know it. Papyrus was a woven mat of reeds, pounded together into a hard, thin sheet. The word "paper" actually comes from the word "papyrus." Later, ancient Greeks used a kind of parchment made from animal skins for the same purpose.

Around 105 A.D., the Chinese invented paper as we know it. They mixed mulberry bark, hemp, and rags with water, mashed it into a pulp, pressed out the liquid. and hung the thin mat to dry in the sun. Paper was born. and this humble mixture set off one of mankind's greatest communication revolutions.

Today, paper is everywhere-billions of tons of it are used daily, most of it disposable and not reuseable without re-cycling. With advances in technology, maybe soon you can have just one paper, e-paper, on which you'll read everything that interests you. Flexible electronic display material similar to paper, reusable and relatively cheap to produce, will be arriving soon.

Xerox PARC has been working on its version for some time: a thin layer of transparent plastic full of millions of small black and white or red and white beads, sort of like toner particles. The beads are contained in an oil-filled cavity. When voltage is applied, the beads rotate to present a colored side to the viewer. The Xerox e-paper is electrically writable and erasable, can be reused thousands of times, doesn't require backlighting or refreshing, operates on low power, and is brighter than today's reflective displays.

Lucent Technologies and E-Ink are working on a 25-square-inch display using electronic ink and active-matrix drive circuits printed on plastic. Transistors in the circuits are made of plastic and then fabricated with a low-cost printing process that uses high-resolution rubber stamps. The e-ink enables the display's paperlike qualities, which include exceptional brightness and contrast under a wide range of lighting conditions, easy viewing from all angles, low power consumption, and plastic film construction.

You'll soon find e-paper in digital books, newspapers, low-power portable displays, fold-up displays, and wall-sized posters.

• The history of paper
• E-paper, here sooner than you think

Behind the byline

Jim Pinto is founder of San Diego-based Action Instruments. You can e-mail him at jim@jimpinto.com, or view his writings at www.JimPinto.com.