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A Super-Efficient Light Bulb 468

Posted by kdawson
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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A Super-Efficient Light Bulb

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  • by Fishchip (1203964) on Saturday March 22, 2008 @05:29PM (#22831874)
    but can I use it in a grow-op?
  • Light pollution (Score:5, Insightful)

    by CRCulver (715279) <crculver@christopherculver.com> on Saturday March 22, 2008 @05:29PM (#22831876) Homepage

    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.

    • by CRCulver (715279)

      Light pollution is already a serious probably ... it's destroyed amateur astronmy

      Geez, of course that should read: Light pollution is already a serious problem ... it's destroyed amateur astronomy.

      • Re:Light pollution (Score:5, Informative)

        by peragrin (659227) on Saturday March 22, 2008 @05:51PM (#22832030)
        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.
        • Re: (Score:3, Interesting)

          by Anonymous Coward
          NO SHIT.

          I live on the 30th floor of an apartment building. One full block away, someone is using a 150 or 300 watt incandescent to light up their backyard. Unshielded of course. 50% of it's light is spilled directly into the sky. It's the brightest visible thing in the entire city, RUINS the entire view of the nighttime cityscape because it's so out of place, and at night casts such brightness on my ceiling that if I don't want to be kept awake by the light, I have to pull my curtains (which pisses me o
          • Re: (Score:3, Funny)

            by ultranova (717540)

            I can't imagine how peeved and angry at him all his neighbours are, the ones who live right next to him.

            Furthermore, it's blinding. I can't see a fucking thing in his back yard. Someone could spend a half hour butchering him with an axe right in the middle of his back lawn, and I betcha NOBODY would see a fucking thing. I couldn't.

            So what you're saying is that the problem will propably solve itself sooner or later ?

          • Re: (Score:3, Informative)

            by mspohr (589790)
            I had a neighbor with an annoying spotlight. I put up a few common red reflectors which gave him a couple of red evil eyes pointing back to his house. Guess what?... the light went off (and stayed off).
    • Re:Light pollution (Score:5, Insightful)

      by merreborn (853723) on Saturday March 22, 2008 @05:46PM (#22831994) Journal

      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.
    • Re:Light pollution (Score:5, Informative)

      by pcruce (1248328) on Saturday March 22, 2008 @05:47PM (#22831998)
      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...
      • Re:Light pollution (Score:5, Insightful)

        by peragrin (659227) on Saturday March 22, 2008 @05:55PM (#22832068)
        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.
    • Re: (Score:3, Interesting)

      by sjames (1099)

      Switch streetlights to a 33% duty cycle with pseudo-random (or really random) timing and instantly reduce power use for street lighting by 66% AND allow people to actually see those mysterious lights in the sky the old Greek dudes were talking about. As a side benefit, studies have shown that crime actually goes DOWN when lights come on at random rather than staying on all the time.

  • Commercial use (Score:3, Insightful)

    by Dan East (318230) on Saturday March 22, 2008 @05:29PM (#22831880) Homepage Journal
    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.
    • Re: (Score:2, Interesting)

      by Anonymous Coward
      I'm pretty sure 6000K refers to the color temperature, I don't think a streetlight could ever reach 5727 Celsius without frying people around it.
      • Additionally, if it really generated that much heat, it couldn't possibly be as efficient as even the worst incandescents.
        • Re:Commercial use (Score:5, Informative)

          by Cowclops (630818) on Saturday March 22, 2008 @05:40PM (#22831952)
          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.

          This isn't dangerous at all.
        • Re: (Score:3, Informative)

          by exploder (196936)
          Temperature is not heat. Once you've got a 6000K plasma (probably not all that costly in terms of energy due to low mass), the amount of energy it takes to maintain that temperature can be quite low. I'm sure the mechanism is very well-insulated thermally.
        • Re:Commercial use (Score:5, Insightful)

          by Geoffrey.landis (926948) on Saturday March 22, 2008 @05:49PM (#22832012) Homepage

          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.

      • Re:Commercial use (Score:5, Interesting)

        by mikael (484) on Saturday March 22, 2008 @06:44PM (#22832334)
        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.
    • Re:Commercial use (Score:5, Informative)

      by exploder (196936) on Saturday March 22, 2008 @05:37PM (#22831936) Homepage
      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.
      • Re: (Score:3, Informative)

        by rs79 (71822)
        Um, folks? All this 3000K and 6000K talk does not mean temperature, it's the color of the light. 5000K is white, or at least the color of equitorial sunlight at noon in the equator, 2700k is tellowish soft light, 7500K is the color of noon in Norway.

        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 Ke
        • Re: (Score:3, Informative)

          by JohnFluxx (413620)
          The post that you are referring to talked about incandescent bulbs and the light bulb in the article. Both of those do operate at a temperature of several thousands of degrees, very close to the temperature color that it emits.
        • Re:Commercial use (Score:4, Informative)

          by forand (530402) on Saturday March 22, 2008 @08:19PM (#22832888) Homepage
          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.
        • Temperature (Score:5, Informative)

          by kf6auf (719514) on Saturday March 22, 2008 @08:32PM (#22832934)
          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.
        • Re: (Score:3, Informative)

          by puppet10 (84610)
          The color of the light is directly related to its temperature if you are generating the light by heating something up (rather than a fluorescent where you are using an atomic or molecular excitation).

          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
        • Re: (Score:3, Informative)

          by J.R. Random (801334)

          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 radiati

    • When they say "6000K temperature" they mean color temperature, not thermal. 6000K color temperature is a match for natural sunlight.

      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.

      Some examples of some common and competitive light sources color temperature and CRI values are:
      # Candle: 1700k 100 CRI
      # High Pressure Sodium: 2100k 25 CRI
      # Incandescent: 2700k 100 CRI
      # Tungsten Halogen: 3200k 95 CRI
      # *Solux Bul

      • by Anonymous Coward on Saturday March 22, 2008 @05:51PM (#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.
      • by poopdeville (841677) on Saturday March 22, 2008 @06:14PM (#22832184)
        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.
        • Re: (Score:3, Informative)

          In light physics, temperature and color temperature are the same thing.

          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.

    • by John Hasler (414242) on Saturday March 22, 2008 @05:50PM (#22832020) Homepage
      > 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.
    • Actually, lighting is only about 1% of total electricity consumption. So switching bulbs to more efficient designs make sweet blue all difference in the greater scheme of things.
      • Re: (Score:3, Informative)

        by Anonymous Coward
        Actually, lighting is only about 1% of total electricity consumption. So switching bulbs to more efficient designs make sweet blue all difference in the greater scheme of things.

        Lighting at 8.8%. [doe.gov]

        Lighting at 22%. [energy.gov]

  • Price? (Score:5, Insightful)

    by danaris (525051) <danaris@@@mac...com> on Saturday March 22, 2008 @05:34PM (#22831908) Homepage

    So...how much does it cost compared to an incandescent? Or an LED?

    Dan Aris

  • by 93 Escort Wagon (326346) on Saturday March 22, 2008 @05:34PM (#22831916)
    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.
  • Where's the story? (Score:2, Interesting)

    by KillerCow (213458)
    I went to the link, but it was just an obnoxious video ad. And no, I didn't sit through it.

    I know that a lot of the stories on here are ads in disguise, but this one isn't even hiding. I didn't realize that slashdot was an a linking to unabashed ads now.
    • I went to the link, but it was just an obnoxious video ad. And no, I didn't sit through it.
      The story was right after the ad. And no, 30s wasn't too long to wait for it.
  • by epilido (959870) * on Saturday March 22, 2008 @05:37PM (#22831934)
    The company makes many different forms of lighting including projectors http://www.luxim.com/ [luxim.com] A home projector with 10 times the bulb life would let me watch just that much more porn in my mom's basement.......
    • Re: (Score:3, Funny)

      by Jesus_666 (702802)
      This bulb is not yet ready for use in projectors. First they have to make it easy to inadvertantly break, hideously expensive and extremely hot while at the same time not very heat resistant. Industry standards, you know.
      • Re: (Score:3, Funny)

        by NormalVisual (565491)
        Don't forget making it into such a form factor as to make it entertainingly difficult to change. Some kind of heavy bayonet-type plug that requires one to push in against an overly-strong spring while twisting on the extremely hot and delicate bulb would be my choice. Extra points to be awarded for making the glass envelope strong enough to work during use but long enough to guarantee breakage while changing it. After all, if you're going to get badly burned, you might as well get cut while you're there.
  • by 3seas (184403) on Saturday March 22, 2008 @05:43PM (#22831978) Journal
    Thats a bright idea.
  • Yes, it was just a little video bite, but the demo was wild!

    I realize that for some reason, lighting technology punches one of my geek buttons. I was super-pumped about white LED technology, and this just blew me away. The bulb was the size of a Jelly-Belly jelly bean, and it out-shone a street lamp fixture the size of a jumbo hot-dog while burning a whole lot less power. How gee-whiz is that?

    At 6000K, though, it's not going to be in my living room, but I'll be really happy to see this in street lamps.

    • > At 6000K, though, it's not going to be in my living room...

      I hate to be the one to break it to you, but I have to tell you that your incandescents are already running at 3000K. If you are so into lighting technology perhaps you might try to find time to actually study up on the subject.
    • by inKubus (199753) on Saturday March 22, 2008 @06:03PM (#22832116) Homepage Journal
      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.
    • At 6000K, though, it's not going to be in my living room
      Do you have regular light bulbs in your living room?
      "When electric current flows through the filament, it heats the filament to a temperature of about 3000 C (about 5000 F), causing the filament to glow [hypertextbook.com] and provide light."
  • But isn't 20,000 hours only a little more than 2 years?


    365 * 24 == 8760

    20,000 / 8760 == 2.283


    Is that right, or am I way off?
  • Ah, some good news. We need more of that.
  • full spectrum? (Score:5, Informative)

    by Councilor Hart (673770) on Saturday March 22, 2008 @06:09PM (#22832158)
    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.
    • Re:full spectrum? (Score:4, Informative)

      by Councilor Hart (673770) on Saturday March 22, 2008 @06:32PM (#22832262)
      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)
    • Black Body Radiation (Score:3, Informative)

      by sd.fhasldff (833645)
      OK, so plasma is not very close to an ideal black body, but regardless you still get some wide spectrum emissions with a peak near that of a corresponding black body. In this case (6000 Kelvin), that's a pretty nice white.
    • Re:full spectrum? (Score:4, Informative)

      by Sycraft-fu (314770) on Saturday March 22, 2008 @06:41PM (#22832318)
      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.
  • Street lights? (Score:4, Interesting)

    by owlstead (636356) on Saturday March 22, 2008 @06:13PM (#22832182)
    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...
  • by Nodamnnicknamesavial (1095665) on Saturday March 22, 2008 @06:16PM (#22832200)
    1. Scalability - will it scale for use in domestic lighting?

    2. Color temperature - will it do warm white or something similarly pleasant?

    3. Argon... isn't that toxic? (since the summary mentioned hazardous materials but didn't point that out, high school chem is so long ago..)

    4. Price if none of the above are problematic

    5. Time to market.

    If someone can answer those, I'll be genuinely interested :)
    • by asc99c (938635) on Saturday March 22, 2008 @06:37PM (#22832296) Homepage
      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 :(
  • by edwardpickman (965122) on Saturday March 22, 2008 @06:17PM (#22832204)
    Full spectrum high efficiency lights would be a major boon to the pot.... I mean industrial hemp growers.
  • by imsabbel (611519) on Saturday March 22, 2008 @06:55PM (#22832400)
    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).
  • What the Spec says (Score:5, Informative)

    by peccary (161168) on Saturday March 22, 2008 @07:07PM (#22832466)
    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.

  • Minor information (Score:5, Informative)

    by dr2chase (653338) on Saturday March 22, 2008 @07:16PM (#22832504) Homepage
    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).

  • Not this again (Score:3, Interesting)

    by Cairnarvon (901868) on Saturday March 22, 2008 @07:38PM (#22832636) Homepage

    There's no mention of mercury or other heavy metals, which pose a problem for compact fluorescents.

    I wish people would challenge memes like these, because they're mostly bullshit crafted to stir up/reinforce discontent, in this case by the right-wing noise machine against "environmentalists", because that sells newspapers.
    CFLs, like all fluorescent lights, do contain a miniscule amount of mercury (and I do mean miniscule; about 4 mg), but to call it a problem is to vastly overstate the dangers involved. If you break a bulb, you may want to open a window for a bit, but that's about it. The clean-up steps the EPA mentions on their website (mentioned in the linked /. post) are there for the hyper-paranoid, and apply just as much to the regular old-school fluorescent tubes (moreso, since they contain more mercury).

    The "problem" is serious enough that if you have a large population that uses CFLs (like places where incandescents aren't allowed anymore), you want to encourage people to dispose of them safely rather than to just throw them with the rest of the trash, but even if the mercury does end up in the environment, it will be less mercury than has been prevented from getting out by its power savings (Wikipedia has this picture [wikipedia.org], which demonstrates the principle for coal plants, but the same thing applies to other types of power plants, except "green" ones like hydroelectric and wind energy; but again, this is only relevant if the bulbs are disposed of unsafely, which is illegal in many places that mandate their use).

  • 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:
    1. Super efficient light (2x as efficient as LEDs)
    2. 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:
    1. The lamps take about 10 seconds to start up.
    2. 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.
    3. They must be mounted atop a very large (about 25cm x 25cm x 15cm) magnetron that generates microwaves.
    4. 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.
    5. The magnetron is bulky, heavy, and noisy
    6. 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.
  • by tinpan (591424) on Sunday March 23, 2008 @12:36AM (#22833962)
    Doesn't beat White LEDs at 300 lumens per watt [newscientist.com].

The first Rotarian was the first man to call John the Baptist "Jack." -- H.L. Mencken

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