Standard room-temperature testing at 350 mA – i.e. pulsed testing rather than steady-state or “hot” testing – was used to achieve the results.
Cree described the result as “a significant advance beyond [our] previous industry record” of 208 lm/W efficacy for an R&D LED, which was reported in February 2010. The company also said the result “further demonstrates how Cree’s relentless innovation continues to push the boundaries of what is possible with LED lighting.”
“It wasn’t long ago when 200 lumens per watt was considered the theoretical maximum efficiency for a lighting-class LED. We broke that barrier in 2010, and have now achieved 231 lumens per watt,” said John Edmond, Cree co-founder and director of advanced optoelectronics.
“The innovation from our labs is the foundation for our industry-leading XLamp LED family and an invention that continues our leadership of the LED lighting revolution.”
Cree says that the results came from an R&D component that features advanced aspects of the same technology used in the company’s XLamp white LEDs. The same level of performance is not yet available in Cree’s production LEDs.
Cree says it believes higher-performance LEDs can enable new LED-based applications and drive down the solution cost of current LED-based designs.