Roll with it

Cambridge Display Technologies and Opsys, leaders in organic light-emitting diode technology, have merged under the name of CDT so they can pool their technological resources.

To create to make flexible roll-up display screens a reality, Cambridge Display Technologies and Opsys, leaders in organic light-emitting diode (OLED) technology, have merged under the name of CDT so they can pool their technological resources.

Cambridge Display Technologies has concentrated on developing displays based on light-emitting polymers which generate their own light when an electrical current is applied.

Opsys, an Oxford University spin-out, has been pursuing the same goal using dendrimers – carbon-based macromolecules with light-emitting cores that also respond to a current.

The new company plans to develop ‘conjugated hybrid’ materials incorporating the most useful products of both firms’ research. , The company claims this will pave the way for a new generation of flat, flexible displays, making ‘roll-up’ screens for devices such as TV sets and mobile phones a reality (see sidebar).

David Fyfe, CDT chief executive, said dendrimers offered significant advantages, particularly as they can be engineered precisely to create materials with very specific, controllable structures.

When combined with CDT’s existing polymers, this should result in displays that are more stable and power efficient. ‘With some clever micro-engineering we think we can develop new materials that offer the best of both existing technologies and more,’ said Fyfe.

Crucially, Fyfe says that both CDT and Opsys have developed materials that can be processed in solutions and deposited on surfaces via inkjet printing. This will be vital for making any future mass-production of OLED displays economically viable.

One of Opsys’s major investors was Japanese printing technology giant Toppan, which had been working with the Oxford company to develop a deposition system. Toppan will now move that investment to CDT, and said it would work with the UK firm to create a coating and patterning process for full-colour OLED screens based on LEP/dendrimer materials.

According to CDT, the merger places it at the forefront of OLED development worldwide, with Eastman Kodak of the US – which has invested heavily in the area – its only serious competitor.

The deal should also accelerate commercialisation, with mass production of OLED devices expected to begin by 2005.

Fyfe claimed that had Opsys remained as a separate entity it would have been ‘at least three years’ further back down the road to commercialisation of its technology than CDT.

CDT already has licensing deals with several major electronics companies, including Philips and Seiko-Epson.

‘By bringing the key intellectual property in this area together under one roof we can stay ahead of the pack,’ said Fyfe.

Sidebar: Displaying an unconventional approach

OLEDs have been tipped as an attractive alternative to conventional displays such as LCDs since the early 1990s.

Unlike other display technologies they need no backlight, making them far more power efficient and thin to the point that they could literally be rolled up when not in use.

The UK has been at the forefront of OLED research since Richard Friend, professor of physics at Cambridge, began researching the light-emitting qualities of various polymers in the 1980s.

Some substances, Friend discovered, gave off light when an electrical current was applied to them. More importantly, by altering the composition of the material, that light could be controlled and manipulated, creating the possibility for a new type of display screen.

CDT, where Friend is now chief scientist, was formed in 1992. Opsys came on the scene with its dendrimer-based system in 1997. But as with all entirely new technologies, commercialisation has been a slow process. No matter how dextrous the scientists become at manipulating the polymers, moving to mass production presents significant problems.

A method has to be found to deposit active OLED elements on to other materials, hence the link-up between Toppan and CDT/Opsys.

The OLED also has to be encased in some kind of protective coating that is thin and flexible enough to meet the needs of the device, while robust enough to withstand everyday wear.

Philips, one of the first licensees for CDT’s technology, recently unveiled a thin-film OLED module. It said the encapsulation process, called PolyLED, will begin industrial production in 2005 – the date fast emerging as the target for full-scale lift-off of the whole OLED sector.