PARIS Promising ultra-thin displays so skinny and flexible they could be rolled up inside a pen or a mobile phone, Polymer Vision, a new technology incubator established by Philips Research, unveiled Monday (Jan. 26) what it claims is the thinnest, most flexible, active-matrix display so far.
The new organics-based quarter VGA (320 x 240 pixels) active- matrix display measures 5 inches on a diagonal, features a resolution of 85 dpi and a bending radius of 2 cm.
With nearly 80,000 thin-film transistors made on plastic instead of conventional glass substrates, the new rollable display is "the largest organic electronics-based display ever reported," claimed Bas van Rens, general manager at Polymer Vision.
Polymer Vision already has built a development line to manufacture 5,000 displays per year. Van Rens said production capability is "a far cry from research," although a run of 5,000 is less than volume production. Polymer Vision plans to "perfect our technology and help our lead customers build prototypes" this year, he said, while it hopes to "increase investment enough to build a pilot line capable of manufacturing millions of displays a year in 2005."
Calling polymer electronics "a very hot field now with lots of competition," van Rens added, "That's why we decided to let the world know what's going on with our latest development before rolling out a finished product."
By 2005, the rollable displays, which can now be used to read e-mail, could initially be used in military applications as electronic, updatable maps on the battlefield, van Rens predicted. The monochrome display offers four gray levels.
The flexible displays were made possible thanks to several breakthrough technologies, including: "electronic ink" developed by E Ink Corp.; polymer electronics-based transistors used to switch pixels on the display; shift registers that can be also made on organic substrates rather than glass; and an improved yield rate for producing five-inch displays.
Electronic ink uses black and white particles with opposite charge encapsulated in micro-capsules. The particles move under the influence of an electric field. Once the power is switched off, the particles stick to a display and become stable, making it ideal for mobile uses that require low-power consumption.
The paper-like readability of the electronic ink makes it suited for applications such as newspapers and e-books.
The flexible, active-matrix backplane has a thickness of only 25 microns one-quarter the thickness of a sheet of paper contains a 200-micron frontplane of reflective electronic ink.
Polymer Vision also developed shift registers based on organic electronics. "We are the first to show the largest functioning circuits on the organic electronics," said van Rens. The implications of the development could allow the company to build complete display drivers on the same organic substrate. That would result in more robust, reliable displays with a reduced number of signal lines and external connections. The shift register technology will be detailed in the February issue of Nature Materials.
Before turning its technology over to Polymer Vision, Philips Research "eliminated a lot of possible roadblocks" for commercialization of rollable displays, according to van Rens. "For one thing, the yield has already gotten much better," he said.
Further, "the life of our organic electronics displays has been already prolonged from "hours to months," he added.
Polymer Vision manufacturers active-matrix backplanes and shift registers using standard production equipment.