LEDs replacing conventional light bulbs for general illumination purposes seems a matter of when, not if.

As well as a matter of who.

Will it be a startup like Switch Lighting or Lemnis, a bigger firm like Lighting Science, or an incumbent like Philips or GE?

Or will it be a firm like the just-unstealthed Soraa? (Their website just came online.)

Soraa of Fremont, California closed an $88.6 million funding round from Khosla Ventures, NEA, and NGEN late last year for its light-emitting diode (LED) and blue laser technology. Dr. Shuji Nakamura, the inventor of the indium-gallium-nitride (InGaN) blue LED is a Soraa founder. Nakamura accomplished something in the early '90s that many considered impossible at the time: a white-light LED. The invention transformed Nichia from a small Japanese manufacturer to a global industrialist. Nakamura also later became a folk hero among salarymen in Japan after suing Nichia for a fair share of the financial rewards.

The Soraa management team is led by Eric Kim, a former Intel and Samsung executive, along with Nakamura, Steven DenBaars, a co-founder of the first company to develop gallium nitride LEDs, Nitres (acquired by Cree); and James Speck.

In 2008, the UCSB professors founded Soraa with the belief that if they could crack the gallium nitride code, they could produce LEDs with market-leading performance. And now the firm is commercializing lamps using gallium nitride as their substrate (rather than the sapphire used in conventional LEDs).

“Soraa has developed the world's highest-performance LED lighting product, which is 80 percent more energy efficient versus incandescents,” said Andrew Chung of Khosla Ventures. “[Soraa’s LED] has a payback of less than a year -- and the potential to shake up the lighting market in 2012 and beyond, as recently reported by GTM's Yoni Cohen.

Soraa is actually two companies in one. Originally, Soraa focused on lasers, while Kaai, another company, focused on lights. The two recently merged. The combined company will produce green lasers for projectors and LED light bulbs that use 75 percent less energy than conventional bulbs.

Lindsay Riddell was able to gather some information about Fremont-based Soraa from investor Vinod Khosla last week as reported in the San Francisco Business Journal. Khosla said that Soraa's standard MR16 light can plug into any outlet and be more than 80 percent more efficient with a payback period of “a few months” (if the bulb is used 15 hours a day, as in a typical commercial application). Khosla said the company revamped the production process for semiconductor chips that produce light. "We decided to redo the ... production process to produce 10 times more of the amount of light per square millimeter than any other substrate," he said.

Note that Soraa is going after the traditional halogen MR16 lamps commonly used in commercial and home applications. According to the press release, the Soraa LED MR16 lamp is priced to achieve less than one-year payback and is meant to replace the 50-watt halogen bulb.  

While some firms go after the incandescent with LEDs, others like Luxim are going after high-intensity discharge lamps.

Add halogen to the list of incumbent lighting technologies that will soon be yielding to more efficient technology.