An efficacious week

The progress in LED technology is nothing short of astounding. Last week I received two press releases that once again show just how quickly the field is advancing.

The first, on Monday, was from Cree (www.cree.com) announcing that it was bringing to market a new family of single-chip LEDs, the XLamp XM, that could deliver an astounding 160 lm/W driven with a 350-mA current. By upping the current to 2 A, designers can have the cool-white device deliver 750 lm an output equivalent to that of a 60-W incandescent bulb but burning up just 7 W; granted, efficacy is reduced a bit, to about 110 lm/W. Also of significance was the fact that the 2C/W thermal resistance of new LEDs is a 350% improvement over Cree’s own XLamp XP-E LED.

The following day I received a release from Seoul Semiconductor (www.acriche.com) that its Acriche family of LEDs devices unique in their ability to run directly from ac sources would be adding devices capable of producing 150 lm/W, an “astounding efficacy [that] will surpass available DC LEDs,” according to the release. Technically that is correct, since the Cree devices won’t be available in production quantities until this fall; but it’s moot because the new Ariche devices won’t arrive until late 2010.

What is significant is that it was only about a year ago that companies were bragging that they’d broken the 100-lm/W barrier. With the rapid rise in the efficiency of converting electricity to light, who know how little energy solid-state lighting will be consume in the near future? Coupled with improvements in thermal properties, this could mean that issues related to operating junction temperature could become insignificant.

I can’t wait to see what comes in tomorrow’s e-mail.