Roll up for the plastic TV screen

By Bill Saunders

By Bill Saunders

9 August 2000

The old television's cathode ray tube may be heading down the same road where the dodo was last seen. In June, a powerful alliance of watchmaker Seiko and inkjet printer company Epson demonstrated a pre-production model of a mobile phone with a full colour monitor, two inches wide.

This is the fruit of a partnership between Seiko-Epson and Cambridge Display Technologies, a British-based firm that has developed a technology which could change the way information is displayed on everything from wristwatches to computer screens. The innovation called Light Emitting Polymers (LED) has significant advantages over the existing Liquid Crystal Display (LCD) used in laptop screens.

When a new technolgy is launched "it begins by making replacements in the existing market", says Dr Daniel McCaughan, Cambridge's president. But the shift from small, monochrome displays to full colour television screens is evolutionary rather than revolutionary, he says. "We know the basic science, although I don't want to underestimate the hard work involved."

LEP technology and, Cambridge itself, began in 1989 with a chance discovery in a Cambridge university laboratory, when Jeremy Burroughes was experimenting with the effect of electricity on plastics called polymers. He found the material glowed seductively when submitted to a low voltage. Dr Burroughes and Dr Richard Friend, his supervisor, went on to start Cambridge. Dr Friend is also Cavendish professor of physics and Cambridge university is a shareholder in the company.

At the same time as they made their discovery, LCDs were making the leap from pocket calculators to the first laptops. Even then the computer industry was warning that the potential of LCDs was limited, the costs were prohibitive of mass-market expansion. LCDs have struggled to keep up with the advances faster processors have brought to computing. As well as being complex to produce, LCDs are too slow to load to capture real-time moving pictures, and images disappear if viewed from the wrong angle. LCDs are also sensitive to temperature, and cannot work on a cold day. And since LCDs are state of the art, the laws of supply and demand drive up their prices.

LEPs, on the other hand, produce solid-state screens that can transmit information at high speeds with low voltages. They are their own light source, so they do not need to be illuminated separately. They are also viewable at any angle. And they are far simpler to produce.

The light-emitting polymers are applied to a conductive polymer substrate as a series of small dots, which is applied to a glass or metal backing. Plastic backings are in development and definitely workable. This is a printing process and can be accomplished with an ink jet printer, hence Epson's involvement. No vacuums or heavily controlled environments are required, as is the case with rival technologies. The process is also relatively environmentally friendly.

Like most polymers, LEPs are organically based, and some LEPs are water-soluble. Given the problems with LCDs, other light-emitting display devices are also in production, also based on glowing molecules. Motorola may well have a mobile with a colour display in the shops within a year. But LEPs are the simplest and cheapest to produce.

The only sticking point is that the colour process has taken time to perfect. All colour display systems are based on breaking colour images into red, green and blue dots. Two years ago, Cambridge demonstrated television screens in monochrome red, green and blue but finally pulled the whole process together this spring. The blue still has to be perfected, hardly surprising since it is the trickiest colour to manage in any colour process.

Cambridge has also established partnerships with Philips and Hewlett-Packard. Dupont is involved in the development of substrates, the name for plastic backings for thedisplays that will ultimately replace the electrified glass and metal backings now used. Plastic will not only be cheaper but more flexible. Why not a television screen that you can roll up and stuff in a drawer when you are not using it? A computer monitor you can read like a newspaper?

Potentially the only limit is the size of your inkjet. Seiko-Epson is working on inkjets that can cover a working area 15ft long at one go. So the video billboard is another possibility. It will be cheap enough to paste it up; then pull it down and bin it two weeks later. And items that require a permanent colour display, such as computers, will be much cheaper to produce.

The latest partnership was struck in May this year with Bayer AG for the development of conductive polymers. The licensing agreements were initiated by Danny Chapchal when he joined the company as chief executive in 1996. His background was in software rather than electronics, and he arrived to introduce a strategy of exploiting the patents rather than developing products independently.

Initially Cambridge had been over-ambitious in hopes of being developer and manufacturer. "One of the problems we've had is that it's not a product but a technology," Professor Friend told Fortune magazine. In 1997, Cambridge had a cash injection of £6m from an investment consortium headed by Lord Young of Graffham, the former Trade and Industry minister. Lord Young also took the post of chairman, with a view to developing partnerships in Japan and South-East Asia.

Last year Cambridge received a further £16m from US venture capitalists Kelso Investments and the US merchant bank Hillman Capital. This investment enabled a move to new premises and made £3m available for new laboratories. Cambridge now employs 80 people.

This January Lord Young moved on, Danny Chapchal moved up to become executive chairman and Dr McCaughan was brought in as president from his post as chief scientist at Nortel Networks.

Dr McGaughan has the highest praise for CDT's relationship with Kelso and Hillman Capital. "I'd be happy to shout it from the rooftops. It's great to work with investors who are genuinely interested." Since Cambridge was founded in 1992 its backers appear to have been drawn to the company as much out of enthusiasm for the technology as for investment purposes. Early supporters included the rock group Genesis.

Sector analysts predict that LEPs will have cornered 10 per cent of the display screen market by 2004. But Dr McCaughan feels this is "the bottom end of the expectation" and the beauty of LEPs will create a demand. The best comparison he thinks is the Walkman. Who would have guessed so many people would want a personal stereo? Certainly not marketing men, says Dr McCaughan. But once people had the chance to get one they did.

The same will apply to LEP devices, Dr McCaughan believes. The luminescent glow will be different from anything we have seen before. "Colour speaks to people" he says. To his company it appears to be saying: riches.