A Super-Efficient Light Bulb 468
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.
Not as low energy as you think (Score:5, Informative)
Re:Commercial use (Score:5, Informative)
A 6000K plasma may even be safer, depending on the density of the plasma.
Re:Commercial use (Score:5, Informative)
This isn't dangerous at all.
Re:Commercial use (Score:3, Informative)
COLOR temperature, not thermal temp (Score:2, Informative)
http://www.fullspectrumsolutions.com/cri_explained.htm [fullspectr...utions.com]
Provides a table of other light sources for comparison and a bit of discussion about color theory. but to answer your point, yes a six thousand degree F bulb would be impractical for home use.
Beware - Parent post links to a virus (Score:5, Informative)
Re:Light pollution (Score:5, Informative)
Somebody please correct my math... (Score:4, Informative)
365 * 24 == 8760
20,000 / 8760 == 2.283
Is that right, or am I way off?
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.
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.
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.
Re:Somebody please correct my math... (Score:5, Informative)
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.
Re:Dual purpose? (Score:4, Informative)
It also says 6000K at its center; I'm not sure whether it transmits that heat to the casing or not.
full spectrum? (Score:5, Informative)
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.
Re:LEDs a better choice (Score:2, Informative)
Re:Dual purpose? (Score:3, Informative)
That won't work, because the temperature it reaches has nothing to do with the amount of heat it emmits. Besides, if it's almost 10 times as efficient as ordinary bulbs, you would have 10 times as much light to get the same heat. You would get warm, but I doubt you would able to sleep with that much light.
Re:Commercial use (Score:4, Informative)
Oh lord.
What do you think color temperature is? It is the temperature at which an ideal black body radiator emits a given light spectrum. It most certainly has to do with the temperature at which an incandescent bulb operates. The hotter the bulb gets, the higher the color temperature. And moreover, the smaller the light emitter becomes, the closer color temperature and operating temperature become.
In this case, it would be physically impossible for a light of any sort to give off that much energy and only consume the amount of electricity available to even a street light.
Temperature isn't energy. Temperature is energy density. For a given amount of energy, the smaller the emitter is, the hotter it will be.
My space heater uses 1500watts and requires I believe 12amps to operate and it would never be able to get anywhere near 6000k even if it were to ignite.
And? The heat emitter is huge. Scale it down to about a 10th its size and run 1500W through it. It will glow a nice bright white before melting.
Re:full spectrum? (Score:4, Informative)
That is 900-1500 nm.
Another few tidbits:
Ar plasma: white
Ar + H2 plasma: red
Ar + O2 plasma: purple-like
Ar + N2 plasma: greenish
Ar + too much current through the copper cathodes: priceless... (lots of copper sparks actually)
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
Re:Commercial use (Score:3, Informative)
It's the color of a body of iron at those temperatures in Kelvin. This has nothing to do with the temperature of the bulb, that is a 7500 degree Kelvin 4 foot fluorescent bulb may be 7500K *in color* but it's barely 80 degrees F in operation. Although degrees Kelvin measures heat like Celsius and Farenheight, it also means "color" becaise of the black body of iron thing.
I'm guessing this lamp is hot but it aint in the thousands of degreesm kelvin or otherwise althouhg I'm quite sure it's a 6000K bulk or whatever.
140 lumens per watt is good but not earth shattering - this is what (high pressure) sodium lamps do already - and are the most efficient bulbs mankind makes. So this is as good but no better than the best we have now. What is good about it is it's small, most plasma lamps aren't.
I'd be interested in knowing what happens to the amount of light per watt as the bulb is made smaller and larger.
Sadly TFV did bad^H^H^Hhorrible things to my machine and there was no FA to read but I'm sure if it's really feasable I'll hear about it soon enough. Not like with those sulfur microwave lamps from a few years back that had similar claims.
Re:Light pollution (Score:3, Informative)
The only "Dark Side of the Moon" I know of is from Pink Floyd. How do you plan to fit a huge observatory on a cd?
Black Body Radiation (Score:3, Informative)
Re:full spectrum? (Score:4, Informative)
Re:Commercial use (Score:3, Informative)
Lighting at 8.8%. [doe.gov]
Lighting at 22%. [energy.gov]
Re:Commercial use (Score:3, Informative)
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.
Re:COLOR temperature, not thermal temp (Score:2, Informative)
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:Light pollution (Score:5, Informative)
The real benefit is for radio astronomy. The far side always faces away from earth, which is a giant radio noise source, and the bulk of the moon itself blocks all the signal. It's really the only place where you won't get such interference (a few space probes notwithstanding).
Re:Light pollution (Score:5, Informative)
I did research on these plasma lamps at Cornell (Score:5, Informative)
The benefits:
The Drawbacks:
They definately have some good applications, like for use in stadiums, airports, etc. However, I think there needs to be more research done to make them usable in homes and automobiles.
Re:Commercial use (Score:4, Informative)
Temperature (Score:5, Informative)
Re:COLOR temperature, not thermal temp (Score:3, Informative)
Correction, for a blackbody, in physics, temperature and color temperature are the same thing.
For an object which is not emitting as a blackbody, "color temperature" means, basically, the temperature that a blackbody would have to be at in order to emit the same color of light, where "color of light" has mostly a lot to do with physics of perception, and not physics of light. For an object that's not a blackbody, "color temperature" is not the same as temperature.
Re:Commercial use (Score:3, Informative)
So in the case of an incandescent bulbs the temperature of the tungsten filament is close to the observed color temperature of the light as the filament is close to being a blackbody radiator (although the bulb itself will be cooler since it is not in direct contact with the filament producing the light).
Since the person in the video explicitly states the full spectrum is daylight-like spectrum is due to the temperature of the plasma in the bulb being around 6000k it is likely (though the person describing in the video may be mistaken - however he is likely better briefed than you or I) that the light is generated from a heating process close to a blackbody radiator although again it is unlikely the bulb envelope itself would be at the 6000K temperature as the plasma would be contained in a small volume within the bulb.
Re:COLOR temperature, not thermal temp (Score:3, Informative)
It kind of makes sense to assume that an incandescent light source is hot because, to quote the all-knowing Wikipedia, incandescence is the release of electromagnetic radiation, usually visible radiation, from a body due to its temperature. [wikipedia.org]
Where I live the lights arent to prevent accidents (Score:3, Informative)
Re:Commercial use (Score:3, Informative)
Um folks, when you're talking about black body radiation the "color temperature" is the temperature. And the glowing object doesn't have to be iron. Glowing argon emits the same way. The video makes it clear that that bitty argon light is 6000 K at the core. I'm sure it's much cooler at the surface of the bulb. With a core temperature of 6000 K most of the energy will be emitted as visible light, not infrared, which of course is the point.
Fluorescent lights do not produce light via black body radiation so their "color temperature" has nothing to do with their real temperature. Likewise with LEDs.
Re:Where I live the lights arent to prevent accide (Score:3, Informative)
I'd rather they spent the money on better quality sidewalks and let our eyes do what they were made to do - adjust to the light.
Re:Crime goes DOWN... (Score:5, Informative)
I'm reminded of a time in my youth, when I was traveling by car with a group of friends. One road out of town has intense streetlights, spaced some distance apart. The darkness between them is amazing. As I blew down the road, definitely "under the speed limit" should any adult have asked, I came across a large, black dog, midway between two streetlights. I swerved across the road, onto the shoulder, and narrowly missed a mailbox and a tree. My friends behind me in another car had no idea what I was doing, until they also almost hit the dog.
No matter how bright they make those streetlights, until there is *uniform* brightness, there will be danger. I wish I knew how to clearly point this out to people.
Re:That's all well and good... (Score:3, Informative)
Re:Beware - Parent post links to a virus (Score:2, Informative)
Re:Short answer.... (Score:4, Informative)
Apparently Sam is a debian developer of some major projects [zoy.org].
If you're interested, the links on the left at that page give some interesting depth of background. He has a long and interesting history.
Be careful with this stuff. The above link goes to his server and they can be changed at any time. They appear to be harmless at the time I'm writing this though. Some of the content is NSFW.
He's apparently a big deal [zoy.org] in IT.
It's possible his server's been owned, but if somebody did that, they did a remarkably convincing job of integrating the bad into the good.
I'm torn here. Responsible geek reaches his dotage at the ripe old age of 30? Trolls have decided to reach over into illegal activity? Some combination of the above? I regret I lack the time and tools to look into it further.
We'll just have to be more careful.
Re:Light pollution (Score:1, Informative)
Re:Light pollution (Score:3, Informative)
Astronomers prefer low pressure sodium too since they can be easily filtered. Full spectrum lights will be the bane of astronomy.
Re:Light pollution (Score:5, Informative)
140 lumens per watt by 2012 would be nice, but I'll believe it when I see it.
Re:Short answer.... (Score:1, Informative)
The real suckers are those of you who didn't believe me when I warned you about Sam's association with GNAA, trolling, scat porn, and the like, before you elected him to Debian Project Leader.
Re:Light pollution (Score:3, Informative)
2. polar regions are always day/night so that's a constant
3. Hubble seems to do ok without an atmosphere
4. even ground based telescopes like my puny 6 incher need some time to equilibrate thermaly
Re:Light pollution (Score:3, Informative)