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A Super-Efficient Light Bulb
Posted by
kdawson
on Sat Mar 22, 2008 05:23 PM
from the it's-little-it's-lovely-it-lights dept.
from the it's-little-it's-lovely-it-lights dept.
Chroniton writes with news of a Silicon Valley company, Luxim, that has developed a tiny, full-spectrum light bulb, based on a plasma of argon gas, that gives off as much light as a streetlight while using less power. The Tic Tac-sized bulb operates at temperatures up to 6000K and produces 140 lumens/watt, almost ten times as efficient as standard incandescent lamps, and twice the efficiency of high-end LEDs. The new bulbs also have a lifetime of 20,000 hours. There's no mention of mercury or other heavy metals, which pose a problem for compact fluorescents.
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That's all well and good... (Score:5, Funny)
Beware - Parent post links to a virus (Score:5, Informative)
Parent
Light pollution (Score:5, Insightful)
Great, people lighting their properties with more bright lights is just what we need. Light pollution is already a serious probably (it's destroyed amateur astronmy, see Mizon's Light Pollution [amazon.com] ). Instead of showing people how they can make do with less lights, we're just making it cheaper for private individuals to duplicate the Las Vegas strip.
Re:Light pollution (Score:5, Insightful)
What makes you think these aren't just going to be used to... replace streetlights? Halving the power usage of streetlights nationwide would reduce atmospheric pollution measurably. If the choice is between light pollution and atmospheric polution...
Parent
Re:Light pollution (Score:5, Informative)
Parent
Re:Light pollution (Score:5, Insightful)
Parent
Re:Light pollution (Score:5, Informative)
Light pollution isn't so much about astronomy but being able to see when it is dark out, because some idiot is lighting up his yard like fen way park. At night less is more. I can use 5 watt 12 volt bulbs and light up your house better than spotlights. more of the house will be lit with less random dark spaces, and more importantly less shadows in which people can hid.
Parent
Price? (Score:5, Insightful)
So...how much does it cost compared to an incandescent? Or an LED?
Dan Aris
they tell you in the video (Score:5, Funny)
Parent
Not as low energy as you think (Score:5, Informative)
Ok, sombody's got to say it..... (Score:5, Funny)
full spectrum? (Score:5, Informative)
God this shit here is worse than digg (Score:5, Insightful)
a) Temperature=!heat=!"OMG IT WILL KILL US!!!". You dont really want to know the "temperature" of the electron beam in your old style TV... (yeah, i know its not in thermodynamical equilibrium, and thus temperature is not defined, thus the "")
b) This is nothing really new. It is based on the same principle like the old sulfure-plasma lamps in the early 90s.
c) It doesnt scale down well. It needs its power provided by microwaves, which is not efficiently possible in the lower power range.
d) Yeah, it uses 250W. But provides as much light as a 1500W halogen thrower. Wake up, moms basement (which you are most familiar with) isnt the world, there are plenty of things you would like to have 10ks of lumens for.
e) Reinforced from d: Yeah, a 250W bulb can be energy efficent. Because it puts out a fucking lot light, numbnut.
f) Doesnt compare at all with leds: Leds have low surface brightness, are effiecent and dont scale UP well. This things have a very high surface brightness, are efficient and dont scape DOWN well. Apple, meet orange.
g) A better comparison would be vs HID: there they are supperior (longer lifetime, less dangerous, not much more complex driver (HIDs need a high-voltage ballast, too).
What the Spec says (Score:5, Informative)
There must be two dozen posts here already blathering about 6000K and nobody bothered to go read the company's official documentation? Here's their website [luxim.com], here are a whole bunch of specs and videos [lifi.com], now go read something before speculating.
Minor information (Score:5, Informative)
However, their light, much like the light of this light, looks an awful lot like the light from a welder. You have to be careful about the pursuit of the almighty lumen -- it's a human-tweaked measure, not a physical measure, and lights score best by dumping all of their light into green. We probably don't want our homes to be lit by exclusively green light.
One thing to note is that there is wide spectrum (true 6000K, this new light), wide spectrum (white LEDs, a relatively smooth blob in the optical frequencies), and wide spectrum (a strategically chosen selection single frequencies, in fluorescent lights). This new bulb should produce very nice looking like, but it might benefit from some of the same phosphors used in white LEDs to down-convert the higher frequencies.
Properly run LEDs are claimed to have lifetimes in the range of 70,000 to 100,000 hours of use, and are not affected by rapid cycling (in fact, the recommended method for dimming them is to switch them on and off very quickly).
Re:Commercial use (Score:5, Informative)
A 6000K plasma may even be safer, depending on the density of the plasma.
Parent
Internal Temperature Doesn't matter. (Score:5, Informative)
> - the risk of fire would simply be too great.
Don't be silly. 6000K is the internal temperature of the gas. The filament in an incandescent lamp can reach 3000K. What matters is the external temperature, which is likely to be lower for a more efficient lamp.
Parent
Re:Commercial use (Score:5, Interesting)
Parent
Re:Commercial use (Score:5, Informative)
This isn't dangerous at all.
Parent
Re:Commercial use (Score:5, Insightful)
To the contrary. The eye's range of sensitivity is tuned to the solar spectrum, emitted at a blackbody temperature just a bit below 6000 K. A bulb is most efficient if it emits light in the spectrum that the eye is sensitive to, and not in, say the infrared spectrum. So a bulb emitting blackbody spectrum becomes more efficient as the emission temperature goes up, and peaks in efficiency at around 6000.
Incandescent bulbs are not inefficient because they are too hot-- they are inefficient because they are not hot enough. They run somewhere about 2500 or 3000, and hence most of the light is emitted in the infrared, not the visible.
Parent
Re:COLOR temperature, not thermal temp (Score:5, Informative)
As other shave pointed out, this is not too much of a problem for household use as ordinary incandescents reach 3600 at the filament. You just need to encase it in a glass bulb.
Parent
Re:COLOR temperature, not thermal temp (Score:5, Informative)
Moreover, this lamp appears to be a high bandwidth lamp -- "full spectrum" as they said. This implies that it does not depend on the absorbsion and emission characteristics of specific atoms. Lamps like these -- fluorescents, high efficiency sodium lamps, and the like -- emit light at discrete wavelengths. High bandwidth lamps depend on incandescence to produce light. Indeed, color temperature doesn't make sense for these kinds of lamps -- no black body radiator will emit discrete spectra. (There's a "corrected" color temperature unit for these lamps used in the lighting trade)
The point is: these lamps get hot. They reach about 6000K.
Parent
Re:Somebody please correct my math... (Score:5, Informative)
Parent
Re:Okay, that was just too awesome! (Score:5, Informative)
Also, if you look at HPS (high-pressure sodium vapor) lamps, the orange ones they use for street lights, the vessel that produces the light is actually quite small. There is an internal tube (made of quartz, I think) that holds the sodium. For the first few minutes, the bulb appears blue because you are seeing an arc in the center of it. After the sodium boils and then turns into a plasma, it is in a higher energy state and starts throwing off photons.
The only difference in this bulb is they are eliminating the electrodes and using a different plasma. They use a high frequency RF that's tuned to the resonate frequency of the gas. Sort of like a microwave does for water, but this is more focused. The gas resonates and becomes a plasma. Then it starts throwing off photons. Your efficiency is limited by how efficiently you can make your RF circuit and amplifier and how focused you can place the RF. I imagine they are quoting the theoretical efficiency but they probably haven't achieved it yet.
Parent
Re:Things I want to know (Score:5, Informative)
2) 6000K is very close to sunlight so yeah it's a nice warm sunny light - should in theory be nicer than incandescent light anyway.
3) No - it's a noble gas (unreactive) and naturally present in the atmosphere, making up nearly 1% of it in fact.
4 and 5) Dunno. I was just searching for the projector bulb version and couldn't find any actually for sale, which given that it was announced half a year ago isn't great going
Parent