Incandescent light bulbs lit the 20th century but the 21st century will be lit by LED lamps—thanks to discoveries recognized by the Swedish Academies of Science
On October 7th, 2014, the Royal Swedish Academy of Sciences announced that the 2014 Nobel Prize in Physics will be awarded to the three Japanese professors, Dr. Isamu Akasaki at Meijo University, Dr. Hiroshi Amano at Nagoya University, and Dr. Shuji Nakamura at University of California, Santa Barbara, for “the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources”.
The advent of the white light source according to the practical application of blue light emitting diodes (LED) brings great benefit to mankind, in the form of home lighting, display devices such as public signals, display backlighting, etc. Conventional white light bulbs create light by heating filaments, making them glow with a low conversion efficiency. Instead, an LED utilizes the recombination of electrons and holes, with good energy conversion efficiency for changing the electric power directly into light. The efficiency of this white light creation is promising for energy saving, as well as its longer-lasting nature. It is also favorable for human health and is environmentally friendly since it does not contain hazardous elements, such as mercury. The blue LED was the final technology necessary for practical white light LED-based illumination based on the triad of red, green and blue LEDs. Red and green LEDs have been available for almost half a century but creation of an effective blue LED has been an elusive challenge for many decades.