Breakthroughs in White LEDs Pave the Way for Changes in the Illumination Industry

Monday, December 01 2008

In 2007, Cree, Inc. of Durham, NC announced a series of breakthroughs in its ongoing research of white light-emitting diode (LED) technology, including the demonstration of a device that can produce as much light as a standard light bulb or fluorescent tube.

Cree’s latest milestone, an - nounced in September 2007, is the 1,000-lumen mark. (A lumen is a measure of brightness as perceived by the human eye.) The company believes reaching this milestone shows that the technology is well on its way to making ordinary incandescent light bulbs obsolete.

Cree, which was funded by Missile Defense Agency (MDA) predecessor, BMDO, also an - nounced in September 2007 that it had improved the efficiency of high-power white LEDs. Spec - ifically, it made a “cool-white” LED that achieved 129 lumens per watt (LPW) —the best results to date for this kind of device — and a “warm-white” version that achieved 99 LPW.

Warm-white LEDs produce an effect similar to the light that comes from incandescent bulbs. White LEDs that operate at lower levels of current can reach even higher efficiency levels.

None of these devices tested last year was made for commercial use. However, Cree will apply what it has learned from the experiments to improve its XLamp® line of LED products. For nearly a decade, Cree has been refining white LED technology in order to offer more efficient, longer-lasting, and cost-effective alternatives to traditional lighting sources.

Already, LED lighting products, including devices that emit colors such as red, green, and blue, last longer than incandescent light bulbs — burning for 10,000 to 50,000 hours, depending on their use. And not only do white LEDs function nearly 10 times as efficiently as ordinary light bulbs, they also outperform halogen bulbs by at least four times, and they outperform some fluorescent bulbs by a factor of 1.5.