MURRAY HILL, N.J., Jan. 23 -- It's the stuff of science fiction: Display screens so light and flexible that you could roll them up and carry them anywhere. That's the inspiration behind a US government-funded research initiative announced recently that will rely on Bell Labs to help create thin, flexible color screen circuitry that should be cheap and easy to manufacture.
The project is being spearheaded by DuPont, of Wilmington, Del., and Sarnoff Corp., of Princeton, N.J., which chose to subcontract part of the research to Bell Labs because of its expertise in organic electronics and materials.
DuPont hopes to develop display panels out of flexible materials lit by organic light-emitting diodes. Sarnoff, formerly RCA Laboratories and the inventor of color television, will work on technology to enable the delivery of signals to flexible screens, thus enabling full-color moving images.
A Bell Labs team will generate new organic compounds and use them to create devices called thin-film transistors (TFTs), to be printed on DuPont's plastic panels. Bell Labs will also design printing processes for stamping the TFTs onto the panels.
The possibilities that flexible displays present are so wide-ranging that the US government is funding the research and development through a three-year grant from the National Institute of Standards and Technology's (NIST) Advanced Technology Program.
Guiding Bell Labs' flexible display screen efforts are Elsa Reichmanis, director of Materials Research, and John Rogers, the labs' director of Nanotechnology Research in Murray Hill, N.J., who will lead the effort to design workable printing processes.
"It's a lofty goal," said Rogers. "If we're successful, the project could have an important economic impact."
Cheap Products, Striking Profiles
That's a key reason NIST is funding the project by providing seed money for the high-risk, yet potentially high-payout program.
Once the collaborators create the materials and perfect the manufacturing and stabilization processes, the displays could be used in everything from cell phones, PDAs and video games to very large screens.
The research trio hopes to produce bright high-contrast display panels with fast refresh rates and a wide viewing angle. The displays won't require the backlighting that's necessary in technologies such as liquid crystal displays, and their striking appearance and thin profile should inspire manufacturers to design appealing products. Plus, they should be much cheaper to produce than current silicon and glass-based screens.
The companies envision displays that will be so flexible they could be rolled up, unlike today's brittle glass screens. The new screens may be printed by presses similar to the ones that print newspapers, as opposed to the complex and expensive techniques for printing on silicon that require sterile clean rooms and temperamental machinery.
Excitement at the Interface
It might even be possible to print them from an ink-jet printer on a desktop, according to Elsa Reichmanis, Bell Labs' director of Materials Research in Murray Hill, who leads the group of chemists who will help design the new TFT molecules.
"Scientists Howard Katz, Christian Kloc and Zhenan Bao are three of the leading organic materials chemists in the world," she said. "They'll design molecules -- figuring out what properties they need to have, what the structure needs to be and how to make them. Then they'll work with John Rogers and the DuPont and Sarnoff researchers on the printing processes and circuitry."
"The ability to interface between disciplines is what allows us to excel in so many fields," Reichmanis said. "I don't believe the expertise could have developed in a university, for instance. It's at the interfaces between disciplines that some of the really exciting work takes place. That's what's novel here."
A Little Bit of Magic
Bell Labs said its leadership in the field was propelled in part by Lucent's relationship several years ago with E Ink, a cutting-edge startup that specializes in the chemistry and physics of displays. Lucent invested in the company through Lucent Venture Partners.
"We had a joint development project that ended more than a year ago," said Rogers. "We combined high-resolution stamping techniques with organic electronic materials and specialized circuit designs for a class of flexible, paper-like displays that we called 'electronic paper.'" The research with E Ink put Bell Labs in the forefront of investigation in the field.
Rogers has been exploring the application of the unusual patterning techniques developed in the course of that work for components that are of direct and immediate interest to Lucent.
"The techniques turn out to have some important applications in photonics and optical networking," he said. These methods, for example, allow circuit patterns to be formed directly on the outside of an optical fiber, which provides a means for tuning its transmission characteristics. Devices that use this general design are incorporated in Lucent's LambdaXtreme transport system announced in March 2002.
The current work with DuPont and Sarnoff may find its way into future Lucent products as well.
"If we can demonstrate the feasibility of the technology, there's no knowing what uses we might find for it," Reichmanis said. "It's a space that's open to imagination."
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