David Crawford investigates the potential of new projection technology.
Fifty years on from its invention of the microchip, US company Texas Instruments (TI) has compressed the technology into a surface area of just 4.3mm. As such, it forms the heart of a new Pico Digital Light Processing (DLP) system that is set to transform travel information delivery for millions of users on the move - by making it projectable.The chip's surface is composed of thousands of microscopic mirrors that switch their orientation at extremely high speeds (it takes just three microseconds for one to change position). The combined array makes up the shape of an LED-generated image, enabling an equipped handheld Pico projector to throw a display that can be up to 1.27m across.
DLP Pico projection technology is a result of more than 10 years' investment in research and development in light manipulation. TI is confident that products with the new system embedded - among the first is the new
Applications such as traffic flow information, route navigation for pedestrians and other travellers and graphic location finding depend on the ability to feature detailed content - typically text-heavy material containing multiple variables and a large amount of data, maps, images and even video content. Much of this can be difficult to see clearly, to the extent necessary to take full advantage of the available information, on the screen of a mobile phone. The problem is worse, of course, for people with impaired sight.
Sharing information
Taking in this level of content is perfectly manageable when it can be viewed on a desktop PC in the prospective traveller's home or office. While on the move, however, finding the precise information needed on a conventional mobile phone screen can take long enough to risk missing the opportunity for an important route decision.But, by being able to display the content on a convenient external 'screen' by using the DLP Pico projector, the user would be able to see all the necessary information and find the relevant details much more quickly. It would also become easier to make good decisions on the best route to take when travelling in a group, as each member would have the opportunity of seeing and discussing the available options.
The 'screen' could be virtually any mainly flat vertical or horizontal surface - the exterior of a building, the ceiling of a tram, bus or railway carriage; the back of an airline seat; or a clear area of a wall or column in a rail or bus station or transport interchange. Providing for this last capability last could lead to the designation of new-style - and highly identifiable - viewing as well as meeting and information points for passengers.
Going further into the planning stage of transportation buildings, it could also encourage the allocation of purpose-designed 'projection panels' along pedestrian access routes and in station and airport retail and leisure outlets and adjoining shopping centres. Making travel information more easily accessible to shoppers and people eating and drinking while awaiting their departures is already part of the commercial strategy of transport hub owners and developers, to enable more profitable use of passenger dwell time.
On the broader front, policy moves aimed at encouraging modal shift from commuters' cars become more practical with easier availability of real-time intermodal travel information.
Practical usage
Anticipating practical concerns, TI stresses that DLP projectors are bright enough to display an image in almost any ambient lit setting. For optimal viewing in a light area, they will produce images about the size of an A4 sheet of paper. Individual manufacturers will decide on brightness controls (for example, in the form of a dial on the projector for passengers to adapt it to specific lighting conditions in the area where they are using it).Images on a DLP-enabled device can be capable of being stored, printed or emailed to (for example) fellow passengers, using relevant input and output ports. Among the potentially 'limitless' applications for the system that TI envisages are more compellingly graphic representations of destination-linked tourist areas and attractions and advertising from, for instance, hotels depicted. The revenues from this could help to support additional services.
Since Pico projection can be viewed as an enhanced extension of anything that can be displayed on a mobile phone screen, there are also possibilities for integration with near-field communication applications.
Key to the embedded mobile phone application is low power use, the subject of continuous research effort by TI. The company envisages at least an hour and a half of usage, to avoid projection using up all the mobile phone's power for the benefit of passengers wanting to make phone calls.
But it stresses that actual battery consumption and other features will be a matter for individual product manufacturers in their own specifications, as stored power efficiency continues to evolve. One potential source of power is energy scavenging, which TI sees as having increasing relevance in handheld and mobile applications. Outside the present embedded mobile phone application, there is scope for future DLP products in providing digital signage for permanent real-time passenger information arrays at rail/bus stations and transport interchanges, and also for portable mini-signs at sites of road or rail dislocation.
DLP availability
The DLP Pico-enabled Samsung W7900 mobile phone is currently available in Korea.
TI is now working with Samsung to bring the product to market in additional regions, and engaging with other consumer electronics manufacturers to develop products built around the DLP Pico projection technology.
Says Frank Moizio, Business Manager, Emerging Products Group/DLP: "Users are already receiving real-time traffic information during their journeys. The possibilities are endless.
"DLP developers have been perfecting miniature projection technologies for years, overcoming challenges such as cooling, battery life, brightness and the complexity of integrating a microchip that's smaller than your fingernail into the world's smallest entertainment and business products. This development process is continual as we get feedback and ideas from our manufacturers and end users.
"Given the level of innovation required to bring these products to market, it is not something that will happen overnight. That said, the next two or three years of innovation are likely to see in a step change in miniature projection technology, with DLP Pico powering projection products that were previously considered impossible."
Digital Light Processing
The DLP chip is an optical semiconductor (known as the 'digital micromirror device') invented by TI to enable the digital manipulation of light. It contains a rectangular array of up to two million microscopic mirrors, each measuring less than one-fifth of the width of a human hair.
These micromirrors are mounted on minute hinges that enable them to tilt either towards (on) or away from (off) the LED light source in a DLP projection system, creating either a light or dark pixel on the projection surface to reflect the image. A bit-streamed image code entering the semiconductor directs each mirror to switch on and off up to several thousand times per second, the frequency with which it does so determining the specific shade of the pixel.
TI, currently the world's third-largest chip maker, has achieved the breakthrough by exploiting and combining new technologies in the arenas of low power, miniaturisation and DLP. First developed in 1987, DLP has so far been used mainly in the entertainment industry, such as in rear-projection TV and digital cinema.
Low-power sensors
Low-power technology is a key area of research interest for TI. Its engineers have, for example, already established that they can generate electricity from unusual sources, including vegetable matter, by using grapes to power a clock.
In another potentially significant transport application, the company has been developing systems that use so little energy that they could poll traffic sensors and relay the resulting data wirelessly without the need for a battery. It is currently working on plans to use the vibrations generated when traffic passes over a bridge to power sensors that can monitor themselves and relay the resulting data to a traffic control centre, for measuring highway flow conditions.
This comes in the context of a widely held belief in the ICT research and business community that the next revolution in computing technology will be the widespread deployment of low-cost, low-power wireless devices. Research carried out at the Berkeley Wireless Research Center in the Department of Electrical Engineering and Computer Sciences at the University of California, Berkeley has demonstrated that low-level vibrations can provide enough power to operate wireless sensor nodes in a range of applications.
The University warns, however, that there is unlikely to be any single energy scavenging solution that will fit all applications and environments. This indicates the need for multiple sourcing.
