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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.
I've spent many a joyful hour gazing at the blue LED. My little blue pals.
It is a pity that their work inspired one of the most horrible trends in consumer electronics design... Seriously, the power light, on the front of the TV, where I'll be staring directly into it while trying to watch something?
Blue is pretty much necessary for LED illumination that doesn't look like some sort of emergency-power-failsafe-lighting scene; but damn is it ever overused...
If you can't see how this advances the science of physics (Auger effect is now fairly understood as a side effect of this) I can't help you.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
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
because some designers decided blue is the new green - the future is blue so let's make our product futuristic. Bah. Very overused.
You don't get it: inciting impotent rage is a *feature*. When you feel rage, everything becomes clear. That's *so* much more satisfying than gnawing, existential doubt.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
It's the first Nobel for a Blue Light Special!
Yes, we do have true white LEDs. The problem is the efficiency isn't up there, and it's based on a new nano-material (I can't remember if it was selenium or tungsten-based.)
We've got remote phosphor tech that works great for producing green - otherwise Cree wouldn't be hitting 300+ lumens per watt (given the lumen is weighted at 550-555nm green)
Also, green light is great for plants. Don't let old science fool you. Why do you think an HPS lamp works so well despite about 80% of its visible light output being green and yellow?
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
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....
We have the lowest concentration of blue sensitive photoreceptors in the fovea centralis, so reading blue lights (or things lit with blue light) is relatively difficult. Indeed, the localization of blue point sources is difficult, making bright blue LEDs look hazy and indistinct even while being blinding.
I can't wait for this trend to end either. I hope my green VFD and LCD alarm clocks hold out. So soothing and easily readable.
If you want a vision of the future, imagine a youtube comments section scrolling - forever.
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.
LEDs are practically by definition monochromatic. They are pn junction diodes. The energy of the photons (aka color) corresponds to the bandgap, and are thus monochromatic. So I'd like to see what you're talking about.
Cree's lab demonstration is not a commercial product; lab demonstrations of all techs are way ahead of commercial realities. Many things you do in the lab simply *can't* be done in the real world at any price. For example, you could gain a couple percent efficiency on metal halide lights by omitting the UV shield, but then you'd be causing permanent vision damage to your consumers. Cree's best commercial LED is 200 lumens per watt, the XLamp XP-L. And FYI, Cree's lab announcement was said to both be "single LED" and "white", which means phosphor, not multiple LEDs of different wavelengths.
As far as I'm aware, the most efficient green LED today yield around 100 if driven nominally, up to around 130-140 if underdriven and well cooled. That's not a figure you'd get in an actual lamp, nor would you use such expensive LEDs in commercial lighting solutions anyway.
LED lightbulbs may very well someday well exceed CFLs. But that day is not today.
No, green light is not great for plants, and I don't know where you got this idea or that it's "old science". There's countless modern peer-reviewed research to support it. The reason plants appear green is because chlorophyl reflects green light. The fact that leaves look black under red or blue LED light is a very good thing. You usually get 2-3 times higher growth per input watt on LED compared to HID, including HPS. HPS has little green, it's mostly yellow, with green and red as the next biggest components. And the worst type of light that exists for growing plants is LPS, which is virtually all yellow. The effect of LPS on plants is terrible.
Yes, the long-term standard for commercial greenhouse light supplementation has been HID, but that's been changing as LEDs drop in price. I know the founder of a company that started a company that produces greens in stackable self-contained "farms". They evaluated different light sources and found that LED gives by far the best bang for their buck. They're hardly the only ones, there's lots of companies switching over.
Side note: I raise a large number of tropicals in Iceland under supplimental lighting.
Beautiful Blueberries
I'm just going to put this out there; you must be REALLY ignorant of what the blue LED has done for optics, solid-state lasers, understanding the Auger effect, crop production under artificial lighting, photobiology, understanding the circadian rhythm, and a whole slew of other things if you think this isn't worthy of a Nobel.
This invention SERIOUSLY helped humanity along.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
I haven't seen any LEDs dying in one or two years. My oldest LED lamp is now 7 years and still excellent. (Doesn't show the kind of degradation that fluorescents often do after a couple of years.) And the cost is dropping fast. A few years ago, I bought a couple of LED bulbs for about $3 each, and they give excellent light.
The really cool thing is that they don't have to be bulbs. LED strips are popular, and can be programmed for different colours or patterns. You can have flat or other surfaces that emit light. The only real problem is that there's no good standard for it yet, so you get lots of different custom solutions with wires all over the place, but I'm sure that problem will eventually be solved, and then we'll have real SciFi lighting in our homes.
That's not the reason for the eyestrain, though.
Blue light actually triggers/worsens macular degeneration. It's such a high-energy photon that it causes physical damage. Long-suspected, recently experimentally confirmed by researchers in Spain.
This is why all of my monochromatic blue/red LED panels come with an eye hazard warning and always have. As soon as you go past sun levels of luminous flux in the blue range, you start hitting levels of retinal damage from photon overexposure in the blue wavelengths.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
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
It seems they usually wait a while to make sure the invention/discovery is actually real. It seems once they awarded the prize, and the discovery turned out to be a misinterpretation of the data.
Contrast this to the method they use for awarding the peace prize, and think which one is better.
"First they came for the slanderers and i said nothing."