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Cree Introduces 200 Lumen/Watt Production Power LEDs 421

ndverdo writes "Cree just announced production power LEDs reaching 200 lumen/watt. Approximately doubling the previous peak LED light efficiency, the new LEDs will require less cooling. This should enable the MK-R series to finally provide direct no-hassle replacements to popular form-factors such as MR-16 spots and incandescent lighting in general. The LEDs are sampling and it is stated that 'production quantities are available with standard lead times.'"
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Cree Introduces 200 Lumen/Watt Production Power LEDs

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  • by Anonymous Coward on Saturday December 29, 2012 @11:57PM (#42424065)


  • Cooling is the issue (Score:5, Interesting)

    by calidoscope ( 312571 ) on Saturday December 29, 2012 @11:57PM (#42424069)
    The reduced cooling should help in lowering the costs of the LED versus the CFL and the reduced energy consumption will be a help as well.
    • by falconwolf ( 725481 ) <> on Sunday December 30, 2012 @12:21AM (#42424171)

      The reduced cooling should help in lowering the costs of the LED versus the CFL and the reduced energy consumption will be a help as well.

      Yesterday I went to Walmart to get new light bulbs, old CFLs I had burned out. There Walmart had LED bulbs in stock, at around $20 a bulb. I ended up going to Sam's to get CFLs, an 8 pack cost less than $6.


      • by aliquis ( 678370 )

        I don't know how it helps or interest someone else but I paid the equivalent of less than $10 for my 650 lumen ones but that was only because they was half price and when I bought it the half price was already in the register but the person selling them also pushed in 50% off so hence I only paid 25% of the original price. And I had actually looked at them at full price earlier because CFLs die so quickly at the toilet and bathroom.

        I also bought 12v spotlights with LED. I wonder if I got the same price ther

        • And I had actually looked at them at full price earlier because CFLs die so quickly at the toilet and bathroom.

          I have had 4 CFL globes in my bathroom for nearly 4 years, and have replaced only one bulb so far. In general, CFLs seem to have a worst case of about 5-6 times the life of an incandescent in the same fixture. I also like the fact that I can get more light when the fixture is wattage/heat limited.

          Other than not being able to use dimmers, the biggest complaint I have with CFLs is that now it's tough to buy just one or two without paying a huge premium. The multi-bulb packs are sometimes so much cheaper pe

          • by aliquis ( 678370 ) <> on Sunday December 30, 2012 @01:38AM (#42424485) Homepage

            It depend on the quality of the bulb.

            Many are listed at 10,000 (or 8,000?) on-off cycles.

            Osram Dulux intelligent longlife for instance is rated at 500,000 on-off cycles.

            Sure it will cost more than the very cheapest CFLs but it's 5 or so times more, not 50 times more. And that's more than my LED lights are rated at (the ones I bought it's even highly rated.)

            Regarding the rating and heat I think it make total sense to at least be able to put a similar power rated light-bulb in the same fixture considering the higher efficiency. I'm not 100% sure it work like that but I can't understand why it shouldn't. Using LEDs those cooling fins get hot but then again a regular lightbulb get very hot to.

            You can get CFLs usable with dimmers to. I think what people should take home with them is that you should buy the CFL which fit your needs, not just any CFL. If it's going to be on for long sure buying any may be ok. If it's going to go on and off often buy one for that, if it need to be dimmable buy one for that and if it will be sitting outside like here and may have a -20 degree C around it buy one designed for that.

          • Bought 10 CFL bulbs for my kitchen. They all died in less than a year.

            • by citizenr ( 871508 ) on Sunday December 30, 2012 @02:44AM (#42424731) Homepage

              Bought 10 CFL bulbs for my kitchen. They all died in less than a year.

              dont buy cheapest chinese shit, but quality CFLs with proper soft start.

        • by ryanov ( 193048 ) on Sunday December 30, 2012 @03:26AM (#42424889)

          I put CFL's in the toilet once, and yes, they did fail.

          • by theedgeofoblivious ( 2474916 ) on Sunday December 30, 2012 @03:45AM (#42424935)

            Well that's the problem. You're not supposed to put them in the toilet.

      • Re: (Score:3, Interesting)

        by ryanov ( 193048 )

        Shopping at Walmart or Sam's hurts America. Don't be a jerk.

        • In what way? Because you care about some store that wasn't able to compete? Because you think workers are mistreated even though most of them don't actually care? Let me guess, you've got no real reason other than some silly ultra-left wing fantasy reasons that the world should be a happy place where everyone gets along and farts butterflies?

      • Yesterday I went to Walmart to get new light bulbs, old CFLs I had burned out. There Walmart had LED bulbs in stock, at around $20 a bulb. I ended up going to Sam's to get CFLs, an 8 pack cost less than $6.

        Paying $6 for eight of them might explain why they 'burn out'...

    • For me, CFLs have worked fine for years but I wish they would make giant LEDs you could screw in like regular light bulbs. Maybe LED technology doesn't work if you scale it up that much, I don't know for sure b/c it isn't my area of expertise. At least they have warmer color temperatures for white LEDs now.
    • by dougmc ( 70836 ) <> on Sunday December 30, 2012 @12:46AM (#42424273) Homepage

      If you double the efficiency, you *more* than half the cooling needed for a given amount of light.

      To give an example with some math ...

      Suppose you need 2000 lumens from a 100 lumen/watt bulb. That means it takes 20 watts of power, and puts out 18 watts of heat.

      Replace it with a 200 lumen/watt emitter that has the same light output, and it now needs only 10 watts of power, and only puts out 8 watts of heat.

      All that said, I'm looking forward to this being available for bicycle lights. Doubling the efficiency means I can have double the light with the same sized battery pack, or the same amount of light with half the battery pack or some permutation thereof. Cooling isn't a big deal for bicycle lights until you get into the really high powered lights as the airflow is usually quite good.

      • Re: (Score:3, Insightful)

        by Anonymous Coward

        One issue with bicycle lights, especially those popular in North America, is that their reflectors are awful. They spray light everywhere. That's only really useful when mountain biking; when cycling on the road, light sprayed into the air is wasted light, and more powerful lights create a hazard for other cyclists and motorists. A good amount of engineering goes into a proper reflector, like those used on car headlights. There are some bike lights that do it right (Phillips has some), but the ones these LE

    • by symbolset ( 646467 ) * on Sunday December 30, 2012 @01:34AM (#42424473) Journal

      These are surface mount LED modules, not bulbs. I checked one out []. At 700 mA @12V (8.4W) gives 1040 lumens - approximately as much as a 70-watt incandescent - in a square 7mm on a side. This is only 123 lumens per watt. Max current is 1250 mA, so you could conceivably get a lot more light out of one, and presumably 1W is where the 200 Lumens/W kicks in, but that's only about a 25W incandescent equivalent - still pretty respectable considering the size. They cost about $10 in quantity 500. ROI is about 6 months vs. incandescent, or 18 months at the 200 lumens/W level.

      I think I could see some interesting applications for this one. At 1040 lumens 18% of the electrical energy is converted to light, so around 6.9 W of heat. It's also too bright to look directly at.

      Yes, it's a slashvertisement / press release. But LED lighting has /. common interests energy, technology, and so on. Progress is progress.

      If they can just improve the efficiency a little more these might be interesting not only as a light source but as a means for spacecraft propulsion.

    • Re: (Score:2, Funny)

      by fotoguzzi ( 230256 )
      Incandescent bulbs will scorch one's fingers. What part of the led or circuitry is so sensitive to heat that cooling is such an issue for led bubs? Would placing the circuitry in a vacuum help at all?
  • by Anonymous Coward on Sunday December 30, 2012 @12:21AM (#42424169)

    ...seems to have the expert analysis. Some people are into flashlights so much and the LEDs that may be used in them, it's crazy what details they keep tabs on.

    Post on the Cree MK-R LED at Candlepower Forums. []

    • flashlights ... and the LEDs that may be used in them, it's crazy what details they keep tabs on

      They have to, since these things are typically ordered from overseas, with prohibitive return postage fees, and many times some manufacturer or vendor will try to become the cheapest by changing to LEDs of a crappy (i.e. fake) rather than Cree variety. When the item arrives, one usually has just a few days to ascertain whether it is genuine or if a refund needs to be requested from the payment service.

    • Wow... a forum about lightbulbs. The true power of the internet is it lets people with similar interests, even if their interests are totally insane, get together. It never ceases to amaze me.

  • jaffa... (Score:3, Funny)

    by Anonymous Coward on Sunday December 30, 2012 @12:28AM (#42424203)

    jaffa cree!

  • For comparative purposes, an incandescent bulb puts out about 52 lumens per watt. This LED is therefore about four times more efficient at converting electricity into light than the traditional lightbulb. That said, one of the big problems with LED lighting is that the light tends towards the blue end of the spectrum, whereas incandescents tend towards the red. Studies have shown that it is blue light that suppresses melatonin production, which in turn upsets the sleep/wake cycle. Similar problems have been

    • For comparative purposes, an incandescent bulb puts out about 52 lumens per watt.

      That's the theoretical maximum, that no bulb actually gets near. For example, a typical 60 watt bulb will give you 15 lumens per watt. []

    • Re:Energy efficiency (Score:5, Informative)

      by timeOday ( 582209 ) on Sunday December 30, 2012 @12:51AM (#42424295)

      an incandescent bulb puts out about 52 lumens per watt.

      If only! "An upper limit for incandescent lamp luminous efficacy (LER) is around 52 lumens per watt, the theoretical value emitted by tungsten at its melting point" (wikipedia). In fact a 40W tungsten bulb outputs 12.6 lumens/watt, up to 17.5 for a 100W bulb. Incandescent bulbs aren't even in the ballpark anymore.

      As to whether some people assume all light is equal, I suppose some do. But others take it very seriously []. It is not an overlooked issue.

    • by Osgeld ( 1900440 )

      you can take the exact same die, slap a different phosphorous on it and make it orange, red, green whatever

      and just FYI CRT monitors use the exact same theory, there is no light bulb, its a electron beam exciting a patch of phosphorus. CRTs can produce the exact same color temperatures as any other monitor

      so please, continue with your ignorant health FUD

  • Is there a theoretical maximum lumens / watt ratio? My 30 second search on Google does't show any relationship between the two terms, but I have to imagine there is some type of maximum...

    • by MyLongNickName ( 822545 ) on Sunday December 30, 2012 @12:49AM (#42424291) Journal

      A 90 second search revealed the following "A common choice is to choose units such that the maximum possible efficacy, 683 lm/W, corresponds to an efficiency of 100%" []

      • by queazocotal ( 915608 ) on Sunday December 30, 2012 @01:10AM (#42424373)

        It's way, way, way more complex than this.

        683lm/W is the maximum luminous efficacy for light, yes, but that's green light.

        To reproduce in full the solar spectrum so that it is indistinguishable from white light requires you to produce a 'white' that produces light from about 400-700nm (UV to IR borders).
        If you take into account flourescence and its effect on colour, perhaps 350nm is the top end.
        This would take perhaps 180lm/W.

        As you move from near-solar (or tungsten) identical bulbs to more limited 'whites' - you get about 250-400lm/W being the maximum.
        This varies from pretty good white that you won't notice being different from actual white to something rather more limited, with just blue at 430nm or so, and greenish yellow at 560nm.
        This will to a cursory glance look right, but will have truly wretched colour reproduction.

  • luminous efficacy (Score:4, Informative)

    by terec ( 2797475 ) on Sunday December 30, 2012 @12:58AM (#42424321)

    Wikipedia has a list of luminous efficacies: []

    200 lm/W seems pretty good; the theoretical limit is around 300 lm/W for LEDs, and that's about 44% overall efficiency.

  • Poor Spectrum (Score:5, Insightful)

    by Anonymous Coward on Sunday December 30, 2012 @01:06AM (#42424357)

    While I *do* love to hear stories like this, and I believe that LED lighting, in some form, is the future, it dissappoints me to see that so-called "white" LEDs still produce quite poor spectra. Check out the spectrum on page 4 of the datasheet given on the MK-R series page. Compare this to the sun's spectrum. Because these are phosphor-based LEDs, you get a relatively narrow blue-violet peak (the true colour of the LED), followed by a wider hump, peaking at about yellow (the broad emission spectrum of the phosphor coating, which is down-converting those blue photons). While this looks "pure white" when you look directly at the beam, it renders colours very poorly (i.e. the reflected light from objects looks the wrong colour). This is what causes LEDs and fluorescent lights to often make a room appear sickly and food look unappetizing. Ideally, we should strive for a light which closely emulates the sun's spectrum, but this is obviously challenging.

    Fortunately, there are a few next-gen LED technologies on the horizon. Quantum dot-based LEDs seem promising. By making dots of a specific size, you can precisely tune the output wavelength of a QD LED. Presumably you can combine a whole bunch of QD LEDs, each tuned to a different wavelength, to approximate the sun's spectrum. Alternatively, certain types of organic LEDs offer the ability to tune the wavelength, and similarly, produce a composite device which has a more ideal spectrum.

    Still, until these materialise, plain 'ol incandescents are the only cheap light sources which produce a nice, continuous blackbody spectrum. Sigh.

    • In reply to a previous Slashdot article on LEDs, this minor effort: []
      The summary is, if you take decent LEDs (CREE or Luxeon) and mix the color temperatures (warm/neutral/cool) it's not bad. Your eyes adapt; the camera is much less forgiving.

      And decent LED kicks the crap out of fluorescent.

  • Cree and me (Score:5, Informative)

    by steveha ( 103154 ) on Sunday December 30, 2012 @03:11AM (#42424841) Homepage

    A year ago, I had no idea who "Cree" might be.

    Then I bought one of these: []

    It's the best pocket flashlight I have ever owned. Bright and useful on "low" power (32 Lumens) and very bright on high (105 Lumens). 500 minutes of light (over 8 hours) from a single AA cell on low, or 110 minutes on high. (I'm trusting the manufacturer's numbers here, but I can verify that it actually is bright and lasts a long time.) Anyway, that's a Cree LED, and it doesn't have the horrible bluish tint of older LEDs I have bought in the past.

    More recently I bought an Ecosmart light bulb at Home Depot. "Ecosmart" is a Home Depot house brand, and uses Cree LED chips. For $10 I got a light bulb that claims to give equivalent light to a 40 Watt incandescent bulb, but seems brighter than that (I think because it's much more directional; it's in a downward-facing fixture so that's fine). []

    And just two days ago I got a fixture that retrofits a 6" can fixture with an LED light. I bought one with the 2700K color temperature, because I like that better than the "colder" lights (bluer, which actually have higher color temperatures). I walked into the store planning to just buy a bulb for my can light fixture, and now I'm very glad I bought the whole Ecosmart fixture. I found an LED light geek web site, and the guy bought one of these just to do a teardown; he found 5 Cree LED chips inside it. Where I live, the power company is subsidizing these lights, so I only had to pay $20 for this light. This dissipates only 9.5 Watts, yet it's very bright. I love the design: it includes three spring fingers to hold it into place, but if you rotate it the fingers collapse and stop holding it. So two decades from now when the LED stops working, it will be easy to remove. []

    So now I want to see Cree make some sort of flush-mount ceiling fixture. I have only found a few flush-mount LED fixtures, and they are all super expensive and I can't find the 2700 K color temperature. I did find one promising looking cheap fixture, but on eBay only and it's an import from China... I have no way to be sure of the quality, other than just buying one and trying it.

    My current plans are just to install some fixtures that have air gaps for circulation, so I can use the Phillips LED bulbs (omnidirectional, not directional like the Ecosmart ones). I'm going to install one of these tomorrow and see how we like it. In case the URL doesn't work right, this is a "Project Source 2-Pack White Ceiling Flush Mount" from []

    Based on my experience with these lights, we are just on the cusp of these becoming mainstream and common. I've been buying these because they are subsidized, but electronics always gets cheaper over time, and within a couple of years or so LED lights should be cheap enough without subsidy that everyone starts buying them. (Even without the subsidy, they make sense long-term versus incandescent bulbs. If you have incandescent lights, consider LED rather than compact fluorescent.)

    P.S. I haven't bought these, but I wish the office where I work would buy them. These are Cree replacement lights for standard fluorescent fixtures. Some companies are making LED lights that are the exact size of a T8 fluorescent bulb, with matching pins; for $60 or $80 or so each bulb, you can replace fluorescents (but you must rewire the fixture to bypass the ballas

    • Re:Cree and me (Score:4, Informative)

      by SuperQ ( 431 ) * on Sunday December 30, 2012 @06:41AM (#42425335) Homepage

      When i was looking into replacing a whole bunch of T12 fixtures, I liked the idea of doing LED. But just upgrading the balasts from magnetic to electronic and switching to good quality T8 tubes works out to be a way better deal. T8 bulbs already do about 90 lumens/watt for a lot less money. I also talked to a good lighting contractor who does efficiency upgrades. He said the tube retrofits don't work so well. It's better to just replace the fixtures and get LED specific fixtures. What we will hopefully get around to doing is a mixture of T12->T8 retrofits for a base lighting level, and then standard LED (PAR-20) spots to light up work areas.

  • by cheros ( 223479 ) on Sunday December 30, 2012 @04:58AM (#42425085)

    When I started working with LEDs they just introduced the LM3909 oscillator - it allowed an LED (only red in those days) to blink for an entire year on a single D cell.

    What keeps amazing me about LEDs is just how little energy they need to start lighting up. I'm not really into electronics anymore (was only tinkering with it since I was 11), but I recall that by using a FET for constant current [] meant you could be pretty flexible about the supply voltage (within limits, of course, the dissipation has to go somewhere), and by researching what it was (been a while) I came across other interesting ideas [].

    As a single, simple component, I find LEDs are about the most interesting ones to experiment with (and LDRs, and NTCs, and .. :) ). They are nice to introduce children to electronics because they instantly do something visible..

  • by hackertourist ( 2202674 ) on Sunday December 30, 2012 @06:45AM (#42425343)

    I've noticed a disturbing trend. Car manufacturers have been using the new lightning technologies to cram e.g. the headlights into ever smaller spaces. The resulting light beam still conforms to regulations, but because the peak intensity is much higher, those headlights are much more likely to dazzle oncoming traffic. The higher the light intensity of the lamp (lm/cm^2) the worse this will get.

Evolution is a million line computer program falling into place by accident.