One of the most common complaints about PDAs is their limited screen size. Most offer a display of 5 by 3 inches or less -- an inevitable restriction given the need to hold them in a single hand.
"With the advent of wireless, PDAs could be very useful for Web browsing, but they're always constrained by the small screen," said John Karidis, a distinguished engineer at IBM. Karidis is part of a research team at IBM's laboratories in Hawthorne, NY working on prototypes for new PDA systems.
One of the more promising designs uses a dual screen, connected by a single hinge, which provides a total display area closer to that used on desktop PCs when the device is unfolded. As with most PDAs, data is entered by touching the screen with a stylus, If larger amounts of input are required, an on-screen keyboard could be used, Karidis said.
A potential problem with that approach is that a double-screen device is difficult to hold in one hand. To work around that issue, a grip runs down the centre of the device on the outside.
The PDA market could certainly use some encouragement. According to IDC data released earlier this week, the total worldwide market for 2003 is likely to drop back to 2000 levels.
One inevitable result has been market consolidation. Palm has recently finalised its acquisition of one-time rival Handspring, and hopes to revive its fortunes by concentrating on devices which combine PDAs with mobile phone functionality. However, such compact devices are even less usable for browsing or other functions requiring a larger screen image.
Having long abandoned the PDA market, IBM has no plans to sell a dual-screen device itself. It would, however, license it to other manufacturers, Karidis said. To be commercially viable, just-emerging organic LED screens would need to drop in price, he added.
IBM has already pursued a similar path of outside licensing with another PDA-like technology, the Meta Pad, which packs most of the components of a normal PC apart from the screen and keyboard into a package about the size of a PDA, which can be plugged into either a portable screen or a desktop adapter. Antelope Technologies will begin selling a device based on the technology in November.
Angus Kidman visited Hawthorne as a guest of IBM.
