At the recent Consumer Electronics Show in Las Vegas, Sony Corp. unveiled a small device with a static black-and-white display that seemed almost quaint. The display on the portable electronic book, however, was one of the few truly innovative technologies in well over 1 million square feet of Vegas exhibition space. The underlying technology, electronic paper, could change the way we read books, magazines and newspapers.
What Is E-paper?
E-paper is an emerging display technology that mimics the age-old process of printing ink on sheets made from wood fiber. Unlike other electronic display technologies, such as picture tubes or liquid crystal and plasma monitors, e-paper does not emit light. It reflects it, just like the traditional printed page. But unlike its pulp-based predecessor, an e-page is not printed once and then discarded or recycled. It is refreshed to display text or images.
With the push of a button during a demonstration, the Sony Reader PRS-500 switched from the title page of The Da Vinci Code to page 1 of the book. E-paper displays text and images by controlling millions of microcapsules printed on a sheet of plastic. Each capsule is filled with clear liquid, positively charged white particles and negatively charged black particles. When a negative charge is applied to the top of a capsule, the white particles move to the top, creating a white pixel on the display. A positive charge creates a black pixel.
While the electronic version has some of the qualities of paper, there are differences. Unlike real paper, this first major U.S. e-paper product is not flexible. Sony encases the e-paper in a hard plastic shell. And its pixels can display only black and white. Researchers are working on both areas. Some have produced flexible versions in the lab. Others have demonstrated color e-paper.
On the Market
Two other products have been announced. Lexar Media will use a small e-paper display on some of its flash memory storage drives to show how much memory capacity has been used. A Massachusetts company, Ambient, will use e-paper for the display on a wireless home weather station. And Seiko has developed a prototype of an e-paper wristwatch. Sony?s Reader uses e-paper in a paperback-sized device that weighs less than nine ounces and allows users to carry the text of up to 80 books. When it goes on the market this spring, it will be the only such device available in the United States, says Ray Ishii, a senior manager in the San Diego firm?s information technology division. Sony launched the device in Japan.
The Sony Reader showcases several of the strengths of e-paper. Unlike an LCD screen, e-paper draws power only when a page is turned. Sony says the Reader will display 7,500 pages on a single battery charge. Previous attempts to sell e-books have failed in part because most people prefer reading printed paper to reading an LCD screen.
?E-paper may be able to unlock the potential of e-books,? says Richard S. Shim, personal computing analyst with technology research firm IDC. ?The problem has always been the display technology.?
Sony says it has high hopes for the paperlike experience of its new product. ?They?re easy for your eyes, and you can read from any angle and also in sunlight,? Ishii says. He says those most likely to use the new reader are frequent fliers, mass transit commuters and techies. The reader?s ability to download documents from personal computers and the Web is expected to make it popular with lawyers and medical professionals. The device has a feature that may make it popular with aging baby boomers. Fonts can be enlarged with the touch of a button, so the bifocals can stay in pocket or purse. The Reader will likely be priced between $299 and $399.