Fujitsu has developed a flexible liquid crystal display (LCD) panel that can maintain the displayed image even with no power supply.
The cholesteric LCD panel, which is the name given to the technology that allows the image to be maintained on-screen, measures 3.8 inches across the diagonal and was on show at the company's Fujitsu Forum 2005 event in Tokyo.
It's the result of about 5 years of research, said Toshiaki Yoshihara, a senior researcher at Fujitsu Laboratories's storage and intelligent systems laboratory, and one of the developers of the panel. He estimated it could be ready for commercialization in 2 or 3 years.
Two versions of the 3.8-inch display were on show. A powered, color display was showing continuously changing images, with each screen refresh taking several seconds, while a monochrome display that hadn't been powered for two weeks was still showing its image.
Also on show were larger panels about 12 inches across the diagonal. They were built on glass substrates and so weren't flexible. Fujitsu was showing these in a mock bus-stop sign that continually changed to show the location of buses, the timetable and other information. The company has dreamed up a number of other uses for the panels, including as electronic advertisements on trains and as displays on smart cards.
Because they require very little power to refresh, the images can be changed by drawing power from the weak radio waves used in contactless smart cards, like those in use on many public transport systems around the world.
Fujitsu is calling the technology 'electronic paper' and also suggested, as do most companies that propose flexible displays, that it might serve in the future as an electronic newspaper. While the displays have high contrast and are flexible almost like paper, they fall short in some areas: they can't be folded and they can't be written on.
Cholesteric LCD panels are also being developed by other companies including Philips Research. In addition, Kent Displays, based in Kent, Ohio, already offers seven types of such panels including an SVGA-resolution (800 pixels by 600 pixels) panel that measures 368 millimeters by 276 mm.