The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2014 to Isamu Akasaki, Meijo University, Nagoya, Japan and Nagoya University, Japan, Hiroshi Amano, Nagoya University, Japan and Shuji Nakamura, University of California, Santa Barbara, CA, USA
“for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources”.
New light to illuminate the world
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 Isamu Akasaki, Hiroshi Amano and Shuji 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 Nagoya University, 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 efficient blue LED is just twenty years old, but it has already contributed to create white light in an entirely new manner to the benefit of us all.
Isamu Akasaki, Japanese citizen. Born 1929 in Chiran, Japan. Ph.D. 1964 from Nagoya University, Japan. Professor at Meijo University, Nagoya, and Distinguished Professor at Nagoya University, Japan.
Hiroshi Amano, Japanese citizen. Born 1960 in Hamamatsu, Japan. Ph.D. 1989 from Nagoya University, Japan. Professor at Nagoya University, Japan.
Shuji Nakamura, American citizen. Born 1954 in Ikata, Japan. Ph.D. 1994 from University of Tokushima, Japan. Professor at University of California, Santa Barbara, CA, USA.
Prize amount: SEK 8 million, to be shared equally between the Laureates.
This year marks the 275th anniversary of the Royal Swedish Academy of Sciences. The Academy 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 endeavours to promote the exchange of ideas between various disciplines.
Nobel Prize® and the Nobel Prize® medal design mark are registered trademarks of the Nobel Foundation.
Isamu Akasaki, Nagoya University
Hiroshi Amano, Nagoya University
Shuji Nakamura, University of California
Zheludev, N. (2007) The life and times of the LED – a 100-year history, Nature photonics, vol. 1, April
Schubert, E. F. och Kyu Kim, J. (2005) Solid-State Light Sources Getting Smart, Science, 308, 1274
Savage, N. (2000) LEDs light the future, Technology Review, vol. 103, no 5, p. 38–44, September–October
Khanna, V. K. (2014) Fundamentals of Solid State Lighting: LEDs, OLEDs, and Their Application in Illumination and Displays, CRC Press