This year's Nobel Prize in physics was awarded to three Japanese-born scientists. Isamu Akasaki of Meijo University, Hiroshi Amano of Nagoya University and Shuji Nakamura of the University of California, Santa Barbara, made the discoveries that brought blue light-emitting diodes into the world.
The technology was first commercialized in 1994 -- as a traffic light. Since then, many of our inefficient lighting fixtures have given way to the bright white light that blue LEDs enable. Corporations as well as entrepreneurs are still figuring out brand new ways we can use the things.
Quite literally, there's a whole new world of applications out there.
According to U.S. research company IHS, the global LED market more than doubled in size in the five years through 2013.
Shortest wavelength
The LED component market has flourished, reaching an estimated $17.7 billion in 2013 and furnishing more than 250,000 jobs, according to IHS figures. The overall market would be even bigger if it included downstream markets, such as lighting, displays, signage, consumer electronics, even Christmas lights.
The incandescent bulb invented by Thomas Edison in 1879 became a 20th-century standard, and General Electric, which Edison co-founded, would later enter the home appliance and power systems markets. That lone invention transformed lifestyles and spawned previously unimaginable industries.
The 21st century will be made over by the blue LED.
In headlights, LED technology is expected to some day make heavy rain or snow seem to disappear. Researchers trying to realize this dream are searching for a way to meticulously control the direction of each LED beam to avert every drop of rain or flake of snow.
LEDs are already transforming concert halls and theaters. Tokyo's Kabukiza Theatre, which reopened in April 2013 after a thorough renovation, was illuminated by a bright white light this past summer. Now that autumn has set in, the place is under another shade of white meant to give it a warmer ambience. It's all done by controlling the color temperature of the LEDs themselves. Each season, the theater will bask in an appropriate hue.
Unlike incandescent bulbs and fluorescent tubes, LEDs allow us to fine-tune a light source's direction, brightness and color. As we better learn to use the technology, we will devise new ways to use light.
LEDs already have a long history; it was in 1907 that Henry J. Round discovered that a semiconductor can emit light when electrical pressure is applied. In 1962, Nick Holonyak, a General Electric engineer, invented the red LED by combining p-type and n-type semiconductors. This was a major breakthrough. In 1971, Junichi Nishizawa, now a professor emeritus at Tohoku University, developed the green LED.
The inventors of the blue LED gained Nobel stature because their discovery made it possible to coax beams of myriad colored light out of semiconductors.
Of the three primary colors, blue has the shortest wavelength, 400 nanometers, compared to red's 600nm. The shorter the wavelength, the higher the degree of light energy.
High-energy blue can be turned into lower-energy red, yellow and other colors through use of fluorescent materials. The white light from today's LEDs is actually high-energy blue toned down in this way.
Before the advent of the blue LED, we were unable to create white or various other LED colors.
4K TVs and their LEDs
A shorter emission wavelength also allows for more data to be stored and read. Thus a Blu-ray player is capable of seeing more data than a DVD player, which uses red light. Their laser technology is based on LED technology.
The blue laser used by Blu-ray devices was also developed by this year's Nobel laureate.
Nakamura was working at Nichia in 1993 when he made it possible to commercialize blue LEDs. In 1994, a year after the company announced that it had successfully developed viable blue LEDs, the cities of Nagoya and Tokushima began using LED traffic lights. Now about 40% of Japan's traffic lights use blue LEDs. Singapore's traffic lights are almost 100% blue LEDs.
Blue LEDs later found their way into flat-screen TVs as backlighting. Sony became the first to market this kind of liquid crystal display TV, in 2004. Blue LEDs have also made thin, low-energy smartphone displays possible.
Until the debut of white LEDs -- made by coating mass-produced blue LEDs with fluorescent material -- TV makers mainly relied on CCFLs (cold cathode fluorescent lamps) to illuminate their TVs' LCD panels.
The Advent of white LEDs lit the path toward thinner and more energy-efficient flat-panel TVs. With fewer components than CCFL backlights, makers could design even thinner TVs.
With the luminous efficiency of white LEDs improving at an annual clip of 20%, the cost of TVs has dropped even as their energy efficiency has improved.
Back in 2008, when the TV backlighting technology really took off, less than 1% of all LCD TVs sold globally used LED backlights. Now LEDs are used in virtually all LCD TVs.
This has forced TV makers to differentiate their products by using even more LEDs. The ultra-high-definition 4K LCD TVs that Toshiba will trumpet this holiday season will feature full-array LED backlighting. In this setup, the LEDs cover the entire backside of the LCD panel, providing greater brightness than a conventional edge-lit LED backlight.
Sony has devised a technology to strictly control the LED backlight to sharpen color contrast and boost picture quality.
Even GE sees the light
As for lighting fixtures, most incandescent bulbs have given way to LEDs. Toshiba stopped making incandescent lamps in 2010; Panasonic followed suit in October 2012. LED fixtures are expected to replace fluorescent tubes, mercury lamps and halogen lighting in offices, stores and warehouses.
According to Fuji Keizai, a Tokyo-based research company, the global LED market reached $16.3 billion last year and is estimated to reach $63 billion in 2020.
Toshiba Lighting & Technology was the first to sell LED lamps for the home, in 2007. Two years later, the market began to expand with the introduction of a 60-watt LED bulb that sold for less than 4,000 yen. The earthquake, tsunami and nuclear meltdowns that rocked Japan in March 2011 made many Japanese consumers conscious about saving energy and helped boost sales of the relatively expensive lamps.
LED lights can last 60,000 hours. Think of never having to change a bulb or tube for more than 10 years. LED fixtures last 20 to 30 times longer than incandescent bulbs and three to five times longer than fluorescent tubes. They consume one-sixth as much power as incandescent lights and about half as much as fluorescent lighting. They now come in a number of shapes and can replace fluorescent tubes.
Mass-producing incandescent lamps and fluorescent lights has several steps. It involves melting glass and trapping electrical discharge material inside of it. To handle the onerous work, huge factories are required. Plenty of expertise is also needed to determine just the right amount of fluorescent substance and the right shape of the electrodes. The industry is pretty much the domain of major electrical equipment makers.
Now a light can be made by putting an LED element on a substrate and covering it with resin. The big obstacle is gaining access to chips, but thanks to the falling price of chips, the price of LED lighting has fallen more than 66% over the past three years, at least in Europe.
Panasonic, Toshiba, Mitsubishi Electric, Hitachi and NEC -- all of Japan -- as well as General Electric of the U.S., Osram of Germany and Philips of the Netherlands are no longer main players. Samsung Electronics and LG Electronics, both of South Korea, are among the new powerhouse.
To gain an edge in consumer lighting, LED makers are offering solutions rather than just something that screws or snaps into place.
In Europe, Philips is leading the pack in so-called "smart lighting," which combines the use of sensor technology to illuminate places where people or cars are heading.
Osram, the world's No. 2 light maker, is also pinning its hopes on smart lighting. The company, which was spun off from Siemens in 2013, offers lighting with brightness and hue variables that can be controlled via a smartphone.
GE said in September that it plans to sell its century-old appliances business to Swedish group Electrolux. But it will keep GE Lighting. In May, U.S. startup ByteLight and GE Lighting unveiled a marketing platform that lets merchants use LED lighting installed in and around their stores to send offers, directions to particular products and information services to shoppers.
Koito Mfg., an automotive lightmaker, developed LED headlights that were adopted in 2007 for the first time by Toyota Motor, which put the lights on its upscale Lexus brand cars. Costs are now lower than they used to be, and LED headlights have made their way to compacts and minivehicles as well. In the fiscal year through March 2014, Stanley Electric developed LED headlights for motorcycles.
According to Tokyo-based Fuji Chimera Research Institute, the size of the global market for automotive LED headlights is expected to total about $926 million in 2014.
Those blue LEDs aren't just for traffic lights anymore.