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.
Time to add nimp.org to your hosts file [wikipedia.org]. The link is an auto redirect from rds.yahoo.com to members.on.nimp.org. This is how Yahoo redirects search results to find out who clicked what. Yawho? search results are thus no longer safe to click. For best results, add rds.yahoo.com to your hosts file or equivalent blocker as well.
members.on.nimp.org resolves to poulet0.zoy.org. The IP address is [80.65.228.130]. Best to block that as well. The DNS administrator for this server is Slashdot User "Sam H [slashdot.org]", UID 3979.
Somebody at slashdot should have a look at our anonymous coward's IP address. It would be nice if we could quit this nonsense. I hope this isn't some troll that bought a low UID in the auction.
And maybe some slashdotter in Paris [domaintools.com] could call Sam [zoy.org] and ask him to fix his compromised [netcraft.com] server [netcraft.com]. It does look like someone truly nasty took it over in August of 2005. Big Debian fan this one. Likes the GNAA routine and the whole bit.
I'm not certain about pinning this on Sam. sam.zoy.org resolves to a different IP. One of you intertubes wizards want to weigh in here?
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.
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.
gives off as much light as a streetlight while using less power.
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.
it also affects drivers, and pilots as well. In some regions airports have pushed for local laws to limit light pollution going up into the sky as it interferes with planes landing. Spot lights can temporary blind drivers causing accidents.
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.
gives off as much light as a streetlight while using less power.
Great, people lighting their properties with more bright lights is just what we need
I missed the part of TFA that said these bulbs were going to be available at prices low enough for home use.
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......light pollution is the more desirable of the two.
The reason we light up the street is because it prevents accidents. Yes, we could save power by turning off the streetlights, but that defeats the purpose of the streetlights, and results in more accidents.
Because our social structures have changed hugely in the last 50 years. Walking home from a friend's house at 1 a.m. is nothing unusual for me, or for lots of other people. But I wouldn't be able to do it if there weren't decent street lighting.
I agree. The reason it hasn't killed professional ground based astronomy is that it is quite easy to subtract the very focused wavelength of sodium vapor streetlights from an image, as sodium vapor lamps are almost completely monochromatic. If we switched to these full spectrum lamps that would be much more difficult, probably meaning we would only be able to do astronomy in very remote areas or with orbiting observatories.
That said, even as strong a proponent of astronomy as I am, the increased efficiency of these lights would probably make it worthwhile...
It is also easy to use shields, and angles to limit the amount of light going up, and only light up the areas that you need to. Besides reflects let you use a lower wattage and still light up the same area.
It's times like these that I wish we'd hurry our dumb asses up and build huge observatories on the far side of the moon.
Fixed that for you. Of course, the real benefit isn't for light pollution (though that's easy enough to take care of when there's no air), since no "side" of the moon is in perpetual darkness. You have about a 336-hour day.
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).
The/. moderation system clearly does not work well. In response to the "troll", however, you don't need to put the telescope somewhere dark on the moon. Having no atmosphere, the moon does not present any difficulties for daytime telescopy since there's no scatter into the objective.
It's hard to be optimistic about LED efficiency improvements these days. The announcements of improvements made by manufacturers over the last few years have yet to make it to the market, and the units I've purchased in bulk typically don't match the ratings. The last project I built with high-efficiency LEDs required that I throw out about two thirds, and that I test every one individually. Of the ones that passed, several failed within the first 1000 hours of use.
140 lumens per watt by 2012 would be nice, but I'll believe it when I see it.
If you had ever spent much time in the countryside, you would know how well you can see by moonlight. I've been out during a full moon on a clear night and been able to play soccer with my friends. Driving requires that we can see dozens to hundreds of yards ahead, so need brighter illumination. We can see just fine outside at night for walking speeds. During the vast majority of our evolution we didn't have artificial light, but we did just fine, we still can.
As a former astronomer, that is patently obvious. However, humanity goes like moths to the lights. It is really hard to teach the average citizen that cutting the luminosity by 80% but tripling the number of lights will make an area much more safe. There is some bizarre connection between bright and safe, when "uniformly lit" would be far, far more safe, regardless of the brightness.
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.
Such high operating temperatures would not be acceptable for domestic use - the risk of fire would simply be too great. But commercial use, specifically for streetlights as the summary mentions, would be ideal. The amount of power consumed by streetlights world-wide must be staggering, so any improvement in efficiency, even in just this single area of light generation, would be substantial.
Temperature isn't the whole story. Regular tungsten-filament incandescent bulbs operate at about 3600K, but it's a tiny filament, and encased in glass, so it's not much of a hazard.
A 6000K plasma may even be safer, depending on the density of the plasma.
Generally what is discussed is black body emission (yes it sounds odd). You need to get a black body to these temperatures to emit the corresponding light. Now since TFA states that the light is full spectrum then it necessarily needs to be at around 6000K to "look" like 6000K. Lights that do not emit at full spectrum do not need to be at the the temperature but instead need to mimic it to our senses.
For any blackbody emitter (incandescent light bulb or this fancy new plasma), the color temperature IS the temperature. It's only for things that don't emit like blackbody radiators (fluorescent and LED) where you have a different color temperature than temperature.
> Such high operating temperatures would not be acceptable for domestic use > - 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.
Heat and temperature are not the same thing. If it produces 140 lumens per watt, I believe that makes it something like 50% efficient (which is insanely high for lighting). That means a 100 watt lightbulb of this technology would turn 50 watts or so into heat, and 50 watts or so into light. A 100 watt incandescant is turning 85 watts into heat and 15 watts into light. So even if it runs at a higher temperature, its confined to a very small space.
However, their talk of efficiency is a bit sensationalist. ZDNet makes it sound like this is the most efficient bulb out there. Actually, the Luxim bulbs are roughly the same efficiency as high pressure sodium lamps (the yellow-tinged ones that are often used for streetlights.)
Additionally, if it really generated that much heat, it couldn't possibly be as efficient as even the worst incandescents.
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.
In the video, the inventors mention that the Argon gas at the centre of the bulb (size of a christmas tree bulb) reaches the temperature of the surface of the sun (6000C). Given the small size of the bulb, there is probably a very steep temperature gradient (otherwise the glass tube would melt). But the energy is dissipated by emitting light of all wavelengths, not just in the infra-red region of the spectrum. I'd be worried about getting sunburn or cataracts from something like this.
by Anonymous Coward
on Saturday March 22 2008, @04:51PM (#22832026)
WTFV (watch the.. video). The temperature they're talking about really is 6000K in heat.
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.
In light physics, temperature and color temperature are the same thing. Color temperature refers to the temperature at which an ideal black body radiator will emit such a spectrum. This unit is obviously a temperature.
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.
This is color temperature. Color temperature has absolutely nothing to do with the temperature that a bulb operates.
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.
I found it interesting that the tiny bulb - at least in the video - was still using 250 watts and internally generated a temperature of 6000K (no they weren't talking color temp; they were talking actual temp). Now that's certainly lower than the 400 watt conventional streetlight they compared it to; but there's no mention in the video about scalability or low-power use. So the submitter's comment about it having advantages over compact fluorescents may have no basis in fact.
but there's no mention in the video about scalability or low-power use
Well they say in the video that it is almost 10 times as efficient in terms of Lumen's per watt (140 vs 15 for a normal bulb). I assume what you mean though is that the new argon bulb might not be able to run at lower powers. So if you just wanted a 60 Watt bulb equivalent, it might not be possible. Is that what you mean?
Lights are not on all of the time. if less than 12 hours use which is likely than your calculations put the life at 5 years in a street light configuration.
Full spectrum with an Ar plasma at 6000K ~= 0.5 eV?
Yes, you can get a lot of light out of it and it looks white, but I wouldn't call it a full spectrum. There are mostly peaks in the region 900-1500 (I don't have a spectra right in front of me right now, so from memory).
But I could be wrong of course.
argh, I am so used to these numbers I don't pay attention to the units anymore.
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)
Full spectrum doesn't necessarily mean perfectly smooth. There are "full spectrum" CCFLs too. As far as I can tell it just means that the white is pretty neutral, and that the spectrum is close to, or 100%, covered. So while this light might not be totally smooth, if it covers 100% of the spectrum, it is full spectrum. Also, the peaks might be something that could be mitigated to some extent with a filter. There are incandescents that do this. The bulb has a bluish tint to it because there is a colour filter on the glass. The net effect is to give a more natural spectrum since incandescents are so heavy in the red-yellow area normally.
Why would we need street lights with a very strong light source using the same spectrum as the sun? What about putting one of these into a beamer instead? Or stadium lights? Every time somebody comes up with a great invention, they seem to want to use it for the weirdest things. Bright sun-light lite disturbs the wildlife anyway, bad idea...
A few points, inspired by those "insightful" comments i read till up to now 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).
According to the product specifications available from Luxim, the actual operating temperature of the surface of the light bulb must be actively cooled to below 850C, and it is recommended that the temperature remain above 650C.
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.
Latest LEDs available (now) go as high as about 90 lumens/watt (Luxeon Rebel, at 350mA, if properly heat sinked). I read, somewhere, that Nichia has demoed an LED at 130 lumens/watt.
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).
When I was a student at Cornell, I worked in the Department of Plasma Physics one summer. We got some money from a startup company to do some research on these same types of plasma lamps. I looked at the spectrum of the light these lamps using a spectrometer. Of particular interest to me was the spectrum during the time when the lamp was starting up. I discovered some spectral lines and was able to determine which elements were present inside the bulb (i.e. reverse engineering). I recall there was sulfur, argon, and trace amounts of a other noble gases like krypton. In any case, here are my thoughts on these bulbs.
The benefits:
Super efficient light (2x as efficient as LEDs)
Gorgeous spectrum. Matches the spectrum of the sun VERY closely. Beautiful white light is emitted and it is extremely intense. I was instructed by my professor to not look directly at the bulb when it was powered on.
The Drawbacks:
The lamps take about 10 seconds to start up.
After they are powered off, you have to wait about 2 minutes before you can turn them back on again. This is because certain elements inside the bulbs (like sulfur) need to cool down, solidify, and redeposited themselves back onto the interior walls of the quartz bulb.
They must be mounted atop a very large (about 25cm x 25cm x 15cm) magnetron that generates microwaves.
The bulb must be surrounded by a Faraday cage (in this case, a metal screen) so that the microwaves are confined to the area around the bulb only.
The magnetron is bulky, heavy, and noisy
The bulb itself gets VERY hot. They can be a fire hazard.
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.
6000K? Who cares? The thing is, this bulb is generating about 10 times the lumens per watt of input power as a standard incandescent. That means that it is dissipating more energy in the form of light and less in the form of heat. Regardless of the internal temperature of the plasma, how "hot" the bulb gets is really a function of the actual dissipated energy. For instance, a spark of static electricity has an extremely high "temperature" but it doesn't burn you. Granted, some of that energy might be occuring in the infra-red range, but I doubt it will be any hotter than a normal bulb.
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.
Answer is (probably) you'd need more of them to heat your house than standard bulbs. This is more efficient at converting energy into light, so it actually produces less heat than a light bulb. It may get to 6000K, but only at a very small point, so the amount of heat produced is quite small. A big radiator full of hot water will be more effective in terms of heat output. A radiator has huge size but a lower output per unit volume, whereas this has a very small volume but a high temperature.
It also says 6000K at its center; I'm not sure whether it transmits that heat to the casing or not.
1) It scales down a bit at least. I'm pretty they were marketing it last year for projector bulbs at around 150W. Not sure whether it scales further down than that.
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:(
That's all well and good... (Score:5, Funny)
Beware - Parent post links to a virus (Score:5, Informative)
Parent
Re:Short answer.... (Score:5, Interesting)
Time to add nimp.org to your hosts file [wikipedia.org]. The link is an auto redirect from rds.yahoo.com to members.on.nimp.org. This is how Yahoo redirects search results to find out who clicked what. Yawho? search results are thus no longer safe to click. For best results, add rds.yahoo.com to your hosts file or equivalent blocker as well.
members.on.nimp.org resolves to poulet0.zoy.org. The IP address is [80.65.228.130]. Best to block that as well. The DNS administrator for this server is Slashdot User "Sam H [slashdot.org]", UID 3979.
Somebody at slashdot should have a look at our anonymous coward's IP address. It would be nice if we could quit this nonsense. I hope this isn't some troll that bought a low UID in the auction.
And maybe some slashdotter in Paris [domaintools.com] could call Sam [zoy.org] and ask him to fix his compromised [netcraft.com] server [netcraft.com]. It does look like someone truly nasty took it over in August of 2005. Big Debian fan this one. Likes the GNAA routine and the whole bit.
I'm not certain about pinning this on Sam. sam.zoy.org resolves to a different IP. One of you intertubes wizards want to weigh in here?
Parent
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.
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: (Score:3)
Geez, of course that should read: Light pollution is already a serious problem ... it's destroyed amateur astronomy.
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
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:Halving power usage of streetlights, easy. (Score:5, Insightful)
Parent
Re:Halving power usage of streetlights, easy. (Score:5, Funny)
Parent
Re:Halving power usage of streetlights, easy. (Score:4, Insightful)
Parent
Re:Light pollution (Score:5, Informative)
Parent
Re:Light pollution (Score:5, Insightful)
Parent
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).
Parent
Re:Light pollution (Score:4, Interesting)
Parent
Re:Light pollution (Score:4, Insightful)
Parent
Re:Light pollution (Score:5, Informative)
140 lumens per watt by 2012 would be nice, but I'll believe it when I see it.
Parent
Re:Light pollution (Score:5, Informative)
Parent
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.
Parent
Commercial use (Score:3, Insightful)
Re:Commercial use (Score:5, Informative)
A 6000K plasma may even be safer, depending on the density of the plasma.
Parent
Re:Commercial use (Score:4, Informative)
Parent
Temperature (Score:5, Informative)
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: (Score:3)
Re:Commercial use (Score:5, Informative)
This isn't dangerous at all.
Parent
Re:Commercial use (Score:4, Interesting)
http://www.ecogeek.org/content/view/1466/74/ [ecogeek.org]
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:Commercial use (Score:5, Interesting)
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: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.
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)
Re:Not as low energy as you think (Score:4, Interesting)
Well they say in the video that it is almost 10 times as efficient in terms of Lumen's per watt (140 vs 15 for a normal bulb). I assume what you mean though is that the new argon bulb might not be able to run at lower powers. So if you just wanted a 60 Watt bulb equivalent, it might not be possible. Is that what you mean?
Parent
Ok, sombody's got to say it..... (Score:5, Funny)
Somebody please correct my math... (Score:4, Informative)
365 * 24 == 8760
20,000 / 8760 == 2.283
Is that right, or am I way off?
Re:Somebody please correct my math... (Score:5, Informative)
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full spectrum? (Score:5, Informative)
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)
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Re:full spectrum? (Score:4, Informative)
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Street lights? (Score:4, Interesting)
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).
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: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.
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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.
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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
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