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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.
But I'm ok with that.
There is no doubt that the blue LED is a great engineering achievement but I'm struggling to see how this really advances the science of physics.
because some designers decided blue is the new green - the future is blue so let's make our product futuristic. Bah. Very overused.
You mean a LCD screen? The LEDs are the backlight.
Because it's just so hard to cover that LED with a small piece of tape?
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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.
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.
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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.