Jeremy Burroughes loves showing off the week's newest color. The current special is a shocking pink. Just the sort of thing a toy maker could use to appeal to young girls, he muses. But this is no ordinary fashion statement. Burroughes, director of technical development at Cambridge Display Technology (CDT), is holding a glowing piece of plastic plugged into a bank of electronic equipment.

The pink glow comes from one of the hundreds of minuscule light-emitting diodes (LEDs) that Burroughes and his colleagues are testing in a back room of CDT's labs in the outskirts of Cambridge, England. There, surrounded by Cambridge University and crammed into a small office building that it shares with three other high-tech companies, CDT is putting plastic LEDs through their paces, testing not just new colors but also how efficiently the devices turn electricity into light and how long they last before the light fades-crucial parameters that will determine the commercial viability of these remarkable new materials, which are known in the trade as light-emitting polymers, or LEPs.