Fuel cell batteries
Long-life batteries will be a key component of future portable devices. Some industry watchers have recognised that a revolution is under way to move from traditional batteries to more efficient "fuel cell" batteries. Early tests from Toshiba have already shown they can power a notebook for five hours.
The fuel cell battery is fed by a small cartridge of methanol and works by converting chemical energy into electricity. The by-products are oxygen and water, which are recycled back into the cell.
Steve Crawley, head of product marketing at Toshiba, said, "Fuel cells will be a big thing because they are very energy efficient. It is also easy to change a fuel cartridge. People may also perceive it as being a greener technology." Crawley anticipated seeing fuel cells in notebooks in two to three years' time.
However, Howard Locker, senior architect at IBM's personal computing division, said, "Unlike current notebook batteries that can plug in anywhere to recharge, fuel cell technology requires users to go to a cell refuelling station to recharge their cells."
Steve Gales, tablet and notebook product manager at Hewlett-Packard, said another problem with fuel cell batteries could be portability. They use a highly compressed cartridge of hydrogen and methanol, which could be explosive. "Aircrafts are very touchy about notebooks, and we are a long way off the Federal Aviation Administration allowing someone to take a canister on a plane," he said.
Organic light emitting diodes (OLEDs) could reduce power consumption and provide brighter screens for portable devices. OLEDs are low-power self-luminescent LEDs that can be painted straight onto glass in three-coloured layers.
Gales said, "OLEDs use a separate LED for each pixel, allowing you to use the screen in bright sunlight. With OLED, you can double a notebook's battery life."
Locker said, "These flexible displays offer fantastic resolution and colour - detail far superior to a standard TFT screen. However, OLED displays are still in their infancy. They can be easily damaged by water and dust particles and last only a little over a year."
OLEDs are also expensive to produce at the moment. But Gales was hopeful for the future. "In the next couple of years OLED technology will appear in mobile phones, in three to four years in PDAs and in six years in notebooks," he said.
Flexible roll-up screens
OLED displays can also be used with flexible plastic screens for portable devices.
Companies such as DuPont and Xerox plan to begin using plastic screens, OLEDs and plastic transistors to build flexible displays within five years.
Crawley said, "Light emitting polymer has been around for six years, but producing it has been a problem, with the quality being hard to guarantee. Polysilicon screens put silicon on the back of a glass substrate, making it lighter and brighter, and more like a 12in SVGA screen." This is something that has been demonstrated by Toshiba.
Crawley said, "The viewing angle is more than 180 degrees and you could almost have people behind the screen. It is more robust but the cost of manufacturing is high. I have seen demos of roll-up membranes that are touch-sensitive - you can tell them to be keyboards or mouse pads."
Another screen technology that Toshiba is testing works more like a cathode ray tube, but does not use electron guns. These surface emitter displays have electrons emitted at each pixel point to produce a bright image. They use a lot of power, but have a very fast response rate.
In terms of notebook interfaces, tablet-style pen input has yet to become mainstream, but there have been advances in handwriting recognition technology.
Gales said, "Handwriting recognition compares handwritten words against a library of thousands of words, but the chances of it getting it right are not brilliant. The new version of the Windows XP operating system uses context-sensitive handwriting recognition, so it knows what you are likely to say."
This has improved the handwriting recognition success rate from about 50% to 99%, said Gales. "Handwriting recognition is a very natural way to input data. We are seeing quite an uptake of tablet PCs, which use handwriting recognition. The slate design is much more like a piece of paper, and I have seen it used in schools for collaboration, and also by ambulance crews and the police," he said.
Voice recognition technology continues to improve. Microsoft is building text-to-speech software into Longhorn, the next version of Windows, but the company has no plans to support voice recognition itself.
Locker said, "Although there will certainly be advances in voice recognition technology, until we achieve true artificial intelligence, computers will still only be able to do what we say, not what we mean. And besides, most of us type just as quickly, and more precisely, than we speak."
Alternative cooling components may appear in the next decade to replace the noisy fan units used in current machines. Several notebook makers are testing radiators that pipe cool water under the processor and other parts of the mobile computer.
Crawley said, "It is twice the cost of a fan to produce at the moment, but there are no moving parts, and it is more efficient. The average fan has a 10-year lifespan, and this can last longer. The downside is that there is liquid in there so it needs good insulation."
IBM has predicted that within five years we will see significant advances in organic storage. The company is developing "Millipede" which uses thousands of nano-sharp tips to punch indentations representing individual bits into a thin plastic film, to create a powerful rewritable disc, said Locker.
This has a data storage density of one trillion bits per square inch - 20 times higher than today's densest magnetic storage, and enough to store 25 million printed textbook pages on a surface the size of a postage stamp.
Locker said, "The result of these advances is, quite simply, storage that uses less power in less space. And as organic storage, unlike magnetic storage, involves no moving parts, these discs will not break. This technology, though expensive, could feasibly bring tremendous data capacity to mobile devices such as personal digital assistants and cell phones."
The shape of things to come
In the future, portable devices will take advantage of more component miniaturisation, for example, smaller size hard drives. Crawley pointed to the 60Gbyte hard drives available for iPods, and 2Gbyte-4Gbyte drives that are the size of a pound coin.
Ubiquitous connections are also on the horizon, where users can take advantage of linked networks to do "open roaming", and keep a laptop link live while going from home onto the road, into the office or onto a train. It uses broadband wireless and landline networks, and technologies such as Bluetooth and 3G. HP said it has helped to build networks like this for two users.
This was first published in January 2005