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Nanotech Could Make Incandescent Light Bulbs As Efficient As LEDs (sciencemag.org)
sciencehabit writes: Thomas Edison would be pleased. Researchers have come up with a way to dramatically improve the efficiency of his signature invention, the incandescent light bulb. The approach uses nanoengineered mirrors to recycle much of the heat produced by the filament and convert it into additional visible light. The new-age incandescents are still far from a commercial product, but their efficiency is already nearly as good as commercial LED bulbs, while still maintaining a warm old-fashioned glow.
There are some crazy innovations happening in LED lighting. To the point where stock on shelves is becoming obsolete in a matter of months.
All white LEDs are essentially florescent lamps. - A blue-range LED excites a phosphor that makes white light. You can tune the phosphor mix to get whatever color range you want. "Warm" Led lights are completely indistinguishable from incandescent, and in may cases can be "Warmer"
So basically you have an emitter with a glob on tob.
In the past everyone was focusing on getting the emitter more powerful, and putting one or two in a light.
That approach is completely obsolete - Too much heat in a tiny space, extremely high drive current requiring more expensive power supplies, light comes from a single point source. (Single emitter is good for some applications but for home lighting its not great)
Now they've developed chip-on-glass techniques that lay down lots of tiny LEDs on a strip of glass which are all then wired in serries, then are covered in a soft polymer that contains the phosphor. The polymer both protects the chips and their wiring while providing a large surface area to emit white light.
The strip arrays are cheap to make (completely automated) and guess what happens when you power a bunch of strips in series (About 80-200 chips at a time)? You can drive it at like 60-100 volts. At that voltage the power supplies are CHEAP because you're only drawing a few hundred ma. Everything gets cheaper and more efficient.
If this was such a good solution, it could probably be used for LED lights as well, since they throw off a non-negligible amount of heat as well.
Unfortunately that is mostly in the form of heating of the LED semiconductor die, relatively little in the form of infrared radiation. So the method presented in the article would have only a small effect on a LED's efficiency (if at all).
And yes, there's a relation between the temperature of an object and how much IR it radiates. But unlike glowing-hot-wires, operating temperatures of LEDs are not in a range where this is a big factor.
Thomas Edison didn't invent much of anything...he just patented the inventions that his staff came up with.
He would only be pleased by this technology if he could get a patent on it. Otherwise, he would probably campaign to squash it, as he did with many of Tesla's awesome inventions.
I'd go urinate on Edison's grave, but that asshole isn't worth the trip out.
I'm old enough to remember taking our burnt out bulbs down to the local Edison to exchange for free new ones.
Needless to say they lasted a hell of a lot longer.
Then Phillips sued, arguing restraint of trade, and won, and that was when I first encoutered rent seeking.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Depends on the state and/or country. Many states/countries banned incandescent bulbs. California almost did, until they were excoriated by environmentalists and economists, saying that only efficiency levels should be regulated.
No, California banned the Edison socket. More precisely, any light with an Edison socket is treated as low-efficiency lighting, presumably on the theory that someone could screw a low-efficiency light bulb in such a socket. It's really stupid to have done so, because now many people are stuck with lighting that only accepts compact fluorescent and the like, while those who have Edison sockets can easily upgrade to the latest and greatest LEDs. There's a loophole, as Edison-socketed lighting is permitted in rooms other than the kitchen, so long as a dimmer switch is in the circuit. This can be even worse, because many high-efficiency lights that fit in Edison sockets are damaged by poorly-designed dimmers.