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2014 Nobel Prize In Physics Awarded To the Inventors of the Blue LED
grouchomarxist writes with word that "The 2014 Nobel Prize in Physics has been awarded to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura, the inventors of the blue LED." From the organization's press release:
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 the University of Nagoya, 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.
Blue LEDs exist, but true "white LEDs" do not. So-called "white LEDs" are blue LEDs with a phosphor over them. They're little more efficient at making "white" light than CFLs.
Red and blue LED light are great for plants, but human eyes are most sensitive to the middle of the visual spectrum, peaking around green. And unfortunately there's still no technology that produces an efficient green LED. That is what is really waiting for a prize. Such an invention could eliminate somewhere in the ballpark of 5% of human energy consumption.
Beautiful Blueberries
I've seen alarm clocks that supposedly have blue LEDs; I will never buy one.
Given that blue light has the strongest disruptive effect on circadian rhythm (no idea whether it's just because blue photons are relatively energetic, or whether we evolved to respond strongly to lights that look rather like the sky during the day, I have no idea; but that's what the research says), you'll really start to need the alarm function after a few nights trying to sleep with one of those....
This was a big breakthrough in condensed matter and optical physics. We learned a lot about how materials doping effects the bandgaps through the development of these GaN/InGaN diodes. The blue LEDs have also been used to build cheap 405nm solid-state lasers for quantum optics experiments without the need for frequency doublers. Nobel prizes in physics usually go to a discovering that generates a lot of follow-up research and shifts the field. Blue LEDs did that in both materials/condensed matter and optics.
No, that's an announcement for a project to try to invent a way to make one. An announcement most notably short on the "how" aspect.
Any particular reason you linked back to this very article yet gave it a different title that only appears on the internet in your comment?
Beautiful Blueberries
And the award for misinterpreting research goes to...
Did you actually read the paper? It's about the benefit of adding different kinds of light in strong white light and finds that green helps most in such a situation because the oversaturation of the outer chloroplasts from red and blue light. There are, of course, countless papers out there that show the main actually tested usage of light is poorer for green, including research that cites that paper (the one I linked found that in some circumstances giving more green light can actually decrease growth - so hey if you like burning more energy to decrease your plants growth...)
Beautiful Blueberries