LED advances herald a bright future

Cree demonstrates light output of more than

1,000 lm from a single LED

Last month, researchers at Cree in Durham, NC, announced they had demonstrated light output of more than 1,000 lm–an amount equivalent to the output level of a standard household light bulb–from a single LED. Driven at 4A, a cool-white device produced 1,050 lm with an efficacy of 72 lm/W.

A warm-white version gave 760 lm with an efficacy (operating efficiency) of 52 lm/W. The company noted that R&D demonstrations generally have been commercialized within 12 to 24 months.

In related developments, the company also said it achieved the best reported efficacy for packaged high-power LEDs. The results were verified by the National Institute of Standards and Technology, with the cool-white (5,813 K) LED producing 135.7 lm with 129 lm/W efficacy and the warm-white (2,950 K) producing 104.2 lm at 99 lm/W. The institute tests LEDs at 350 mA and measures output after five minutes of operation to ensure that the device has achieved thermal stabilization.

Paul Scheidt, a Cree product marketing manager, notes that these developments are “proof points” that it is possible to get to higher levels of LED performance, such as 150 lm/W that the Department of Energy expects to be achieved in 2010-13. For more information, contact Cree at 919-313-5300 or visit www.cree.com

Richard Comerford