Lighting Up Our World with LED: 2014 Nobel in Physics

By Shlomo  Maital

Winners of the 2014 Nobel Prize in Physics

 Three Japanese scientists have won the 2014 Nobel Prize for Physics, for their contribution – lighting up the world with LED – light emitting diode technology.

   According to today’s New York Times:  The three scientists, working together and separately, found a way to produce blue light beams from semiconductors in the early 1990s. Others had produced red and green diodes, but without blue diodes, white light could not be produced, the Royal Swedish Academy of Sciences said in its prize citation. “They succeeded where everyone else had failed.”   The Nobel committee said that light-emitting diodes, or LEDs, would be the lighting source of the 21st century, just as the incandescent bulb illuminated the 20th.

    The New York Times noted:    “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,” the Nobel committee said. “Due to low power requirements, it can be powered by cheap local solar power.”

   According to Wikipedia,  “a light-emitting diode (LED) is a two-lead semiconductor light source:  basic …  diode, which emits light when activated.  When a voltage is applied to the leads, electrons are able to recombine with electron holes within the device, releasing energy in the form of photons. This effect is called electroluminescence, and the color of the light (corresponding to the energy of the photon) is determined by the energy band gap of the semiconductor.” 

   The three Japanese scientists managed  to achieve “the invention of efficient blue light-emitting diodes, which has enabled bright and energy-saving white light sources.”   Previously, light was created with LED technology, but in colors that did not enable replacement of the Edison incandescent bulbs. 

    Nakamura worked for a time for a Japanese company, Nichia. Nichia awarded him…$200 for his invention.   Nakamura left the company in 1999 to join U. of California, Santa Barbara, and sued the company for a fair share of the immense royalties. He settled for $8.1 million.