Cree Inc developed a white LED whose luminous efficiency is as high as 254lm/W and announced it at Light+Building 2012.
This time, Cree broke the efficiency record of 231lm/W, which was also realized by the company. The color temperature of the white LED is 4,408K. The new record was realized at a room temperature when current was reduced to 350mA.
The maximum luminous efficiency of white LEDs made by combining blue LEDs and yellow fluorescent materials, the combination that can realize the highest efficiency, is said to be about 260lm/W.