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2014 Nobel prize to Professor Nakamura for Blue-light diodes. read more

Shuji Nakamura from Santa Barbara University, Isamu Akasaki, and Hiroshi Amano from Nagoya University won the 2014 Nobel Prize in Physics for their invention of efficient blue light-emitting diodes which enabled bright and energy-saving light sources.
DVN interviewed Shuji Nakamura about his work one year ago:

Pr Nakamura, winner of Nobel Price, interviewed by DVN
In order to collect the best information about the future of lighting concerning LED and Laser technologies, DVN was in Santa Barbara, one year ago, to interview Professor Nakamura.
Nakamura Shūji, winner of the Nobel price 2014, is a professor at the Materials Department of the College of Engineering, University of California, Santa Barbara (UCSB) and is regarded as the inventor of the white LED, He gave this exclusive interview to DVN. The complete interview is integrated in the report on laser technology published by DVN.

Below is an extract of the interview published in the DVN report named “Automotive Lighting TechnologiesTrends and Forecasts to 2025” published in May 2014

About LED
Definitely LED sources will have a big impact on the market. Power consumption reduction will be a major driver, either in General Lighting, street Lighting or in Automotive.
About white evolution, physical limit in such conditions is probably around 300lm/W, it seems consequently reasonable to reach 200lm/W as a maximum. I feel that we should be able to double current efficiency in the next 10 years.

About Laser Diode technology
I strongly recommend Laser Diodes technology. Reliability is high and there is no limitation in power. You add several Laser Diodes together in the same package to get the power you need. In theory, it is possible now to design a Laser Diode with 10000 lm output, consuming 100W.
Today you can have Laser Diodes delivering 4 times more Lumen than LEDs. Efficiency is about the same than LEDs or may be a little higher in the future, but there is no drop in Lumen output while increasing the current. Laser Diode can be controlled either by constant Power or constant current.

Operating temperature should not be an issue; 100°C is totally acceptable for a Laser Diode without any degrading performance. Cost should be cheaper, as you will need only one Laser Diode Source to get the total Lumen output you need versus several needed with LEDs. The only negative point is the failure behavior. When degrading, Laser Diodes stop emitting completely, while LEDs degrade slowly, loosing step by step lumen output. Attention should be given at the same time, not degrading phosphor layer with too much power.

You should not have any issue with Laser Diode usage with regulation as the user will not see the Laser Diode directly, but only the phosphor surface scattering the light.