http://techon.nikkeibp.co.jp/english/NEWS_EN/20050622/106025/
Citizen Electronics Co., Ltd. has developed the CL-L100 series of white light-emitting diodes (LEDs) claiming the world's most intense light beam of 245 lm per package. The power supply needed to create the 245 lm beam is 3.5 W, with light emission efficiency reaching 70 lm/W. "This efficiency is almost equivalent to a fluorescent bulb," said a company spokesperson. If ten of these white LEDs are connected and operated at 12 V, a beam of 2,450 lm can be generated at 35 W. This represents about 60% the power consumption and about 1.6 times the beam intensity of an automotive halogen lamp.