Flexible displays ready for roll-out

02 Mar 2005

Roll-up displays get ready for use by designers of portable electronics.

The Dutch electronics firm Philips says that its roll-up display technology now has a performance to suit portable electronic devices. The news comes just 12 months after the firm’s Polymer Vision business unit demonstrated its first prototype (Philips reveals roll-up display) - a monochrome 5-inch diagonal QVGA (320x240 pixels) display that was 300 microns thick and had a bending radius of 2 cm.

Paper like performance

According to Philips’ Hans Driessen, Polymer Vision has spent the last year improving the specifications, lifetime and yield of the display so that it is practical for use with the next generation of PDAs and mobile phones.

Potential applications include use as a portable external display for viewing large documents such as electronic maps or pages of text, for example. “From the middle of 2005 these displays can be designed into products,” he told Optics.org. “They now offer a better readability than newspaper.”

The ultrathin display consists of two parts - the visual front end (a bi-stable electrophoretic display made by the US firm E ink) and the backplane polymer electronics (developed by Philips). When not in use they can be rolled up for convenient storage.

“The latest version is three times thinner at just 100 microns thick and has a tighter roll-up radius of 7.5 mm,” explained Driessen. “We’ve also improved the mechanical lifetime by a factor of 100. Last year’s prototype could be rolled up 100 times [before failure], now that has increased to 10,000 times.”

Ideal for maps

Although the size and resolution of the display is still the same as the initial prototype, it now boasts an enhanced reflectivity of 40% and a 10:1 contrast ratio (4 gray levels) which allows reading even in bright sunlight. Large versions that support color are also in the product roadmap.

Six months ago, Polymer Vision opened an experimental production line to produce evaluation samples. “We are now focusing on the manufacturing and are looking for partners and venture capitalists to help bring the technology to market, perhaps through a joint-venture or spin-off,” said Driessen.

Author
Oliver Graydon is editor of Optics.org and Opto & Laser Europe magazine.