The three researchers won the award for their invention of diodes that emit blue light, “which has enabled bright and energy-saving white light sources,” the prize-awarding committee announced in Stockholm today (see press release).

Combining blue, green and red diodes creates a long-lasting, efficient white light. But despite earnest industry efforts to work out how to get gallium nitride-based semiconductors to shoot out blue beams, it took until the 1990s before Akasaki and Amano – working together at Nagoya University in Japan – and Nakamura, working at a company in Tokushima called Nichia Chemicals, made the breakthrough.

Nakamura, like the other winners, was born in Japan. But in 2000, he left the country to take up an academic position at the University of Santa Barbara in California, and is now a US citizen. At the time, he said that the United States offered better working conditions: “Japanese industrial research and development may be on its way to becoming obsolete.” He later sued Nichia Chemicals over the compensation he received for inventing the blue LED technology, in January 2005 eventually settling for ¥840 million ($7.6 million at the time).