STOCKHOLM (AFP) - Three Japanese-born researchers on Tuesday won the Nobel Prize for Physics for inventing the LED lamp, a boon in the fight against global warming and aiding people in poverty.
The trio are Isamu Akasaki, Hiroshi Amano and Shuji Nakamura, a researcher who is currently a US national based in California.
"This year's Nobel Laureates are rewarded for having invented a new energy-efficient and environment-friendly light source - the blue light-emitting diode (LED)," the jury said.
"Their inventions were revolutionary," it said. "Incandescent light bulbs lit the 20th century. The 21st century will be lit by LED lamps."
The three researchers produced bright blue beams from semiconductors in the early 1990s, triggering a transformation in lighting technology, according to the jury. Red and green diodes had been around for a long time - but without blue light, white lamps were impossible. Devising the blue LED was a challenge that endured for three decades.
"They succeeded where everyone else had failed," the jury said. It added: "With the advent of LED lamps we now have more long-lasting and more efficient alternatives to older light sources."
LED lamps emit a bright white light, last for tens of thousands of hours and use just a fraction of energy compared with the incandescent lightbulb pioneered by Thomas Edison in the 19th century.
The most advanced LED lamps now consume nearly 20 times as little electricity as regular light bulbs and their performance is improving constantly.
Around a quarter of world electricity consumption is used for lighting, so governments in many countries are promoting a switch to LEDs to save heat-trapping emissions from fossil fuels, which are burned to generate power.
And because they have very low electricity needs, LED lights can be connected to cheap, local solar power - a benefit for the more than 1.5 billion people around the world who lack access to the electricity grid.
"The invention of the blue LED is just 20 years old, but it has already contributed to create white light in an entirely new manner to the benefit of us all," the jury said.
Unusually for a recipient of the Nobel Prize, Nakamura was employed at Nichia Chemicals, a small Japanese company, when carrying out the research that was rewarded on Tuesday in Stockholm.
"It's unbelievable!" Nakamura said when phoned by the Nobel Committee.
Akasaki worked together with Amano at the University of Nagoya, when conducting their part of the path-breaking research.
Akasaki, born in 1929, is currently a professor at Meijo University in Nagoya, while Amano, born in 1960, is a professor at Nagoya University. Nakamura, born in 1954 in Japan, is now a US citizen and a professor at University of California, Santa Barbara.
The winners will share the prize sum of eight million Swedish kronor (S$1.42 million).
Last year the award went to Peter Higgs of Britain and Francois Englert of Belgium for the discovery of the "God particle", the sub-atomic Higgs boson which gives mass to other elementary particles.
In line with tradition, the laureates will receive their prize at a formal ceremony in Stockholm on Dec 10, the anniversary of prize founder Alfred Nobel's death in 1896.