STOCKHOLM — The Royal Swedish Academy of Sciences announced Oct. 7 that it has decided to award the Nobel Prize in Physics for 2014 to Isamu Akasaki of Meijo University and Nagoya University, Hiroshi Amano of Nagoya University, and Shuji Nakamura of UC Santa Barbara “for the invention of efficient blue light-emitting diodes, which has enabled bright and energy-saving white light sources.”
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). In the spirit of Alfred Nobel, the prize rewards an invention of greatest benefit to mankind; using blue LEDs, white light can be created in a new way. With the advent of LED lamps we now have more long-lasting and more efficient alternatives to older light sources.
When Akasaki, Amano and Nakamura produced bright blue light beams from their semi-conductors in the early 1990s, they triggered a fundamental transformation of lighting technology. Red and green diodes had been around for a long time but without blue light, white lamps could not be created. Despite considerable efforts, both in the scientific community and in industry, the blue LED had remained a challenge for three decades.
They succeeded where everyone else had failed. Akasaki worked together with Amano at the University of Nagoya, while Nakamura was employed at Nichia Chemicals, a small company in Tokushima. Their inventions were revolutionary. Incandescent light bulbs lit the 20th century; the 21st century will be lit by LED lamps.
White LED lamps emit a bright white light, are long-lasting and energy-efficient. They are constantly improved, getting more efficient with higher luminous flux (measured in lumen) per unit electrical input power (measured in watt). The most recent record is just over 300 lm/W, which can be compared to 16 for regular light bulbs and close to 70 for fluorescent lamps.
As about one-fourth of world electricity consumption is used for lighting purposes, the LEDs contribute to saving the Earth’s resources. Materials consumption is also diminished as LEDs last up to 100,000 hours, compared to 1,000 for incandescent bulbs and 10,000 hours for fluorescent lights.
The LED lamp holds great promise for increasing the quality of life for over 1.5 billion people around the world who lack access to electricity grids: due to low power requirements it can be powered by cheap local solar power.
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.
Akasaki was born in 1929 in Chiran, Japan. He received his Ph.D. in 1964 from Nagoya University, where he is now a distinguished professor. He is also a professor at Meijo University in Nagoya.
Amano was born in 1960 in Hamamatsu, Japan. He received his Ph.D. in 1989 from Nagoya University, where he is now a professor.
Nakamura, an American citizen, was born in 1954 in Ikata, Japan. He received his Ph.D. in 1994 from the University of Tokushima and is now a professor at UC Santa Barbara.
Prize amount: 8 million kronor ($1.1 million), to be shared equally among the laureates.
This year marks the 275th anniversary of the Royal Swedish Academy of Sciences, which was founded in 1739 and is an independent organization whose overall objective is to promote the sciences and strengthen their influence in society. The academy takes special responsibility for the natural sciences and mathematics, but endeavors to promote the exchange of ideas between various disciplines.
For more information, visit www.nobelprize.org.