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Technology Science

Breakthrough In LED Construction Increases Efficiency By 57 Percent 182

Zothecula writes: With LEDs being the preferred long-lasting, low-energy method for replacing less efficient forms of lighting, their uptake has dramatically increased over the past few years. However, despite their luminous outputs having increased steadily over that time, they still fall behind more conventional forms of lighting in terms of brightness. Researchers at Princeton University claim to have come up with a way to change all that by using nanotechnology to increase the output of organic LEDs by 57 percent.
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Breakthrough In LED Construction Increases Efficiency By 57 Percent

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  • by GameboyRMH ( 1153867 ) <gameboyrmh@g m a il.com> on Friday September 26, 2014 @01:41PM (#48004779) Journal

    Your equipment will now have 57% brighter indicator LEDs on the front to burn your retinas at night!

    • by Anonymous Coward on Friday September 26, 2014 @01:50PM (#48004845)

      Easily fixed with a piece of electrical tape - to hold your eyes shut.

      • by chaosdivine69 ( 1456649 ) on Friday September 26, 2014 @03:09PM (#48005411)

        This is quite funny. Though refrained taping my eyes shut (and I'm not a vampire), I did just last night, go around my room and put pieces of black electrical tape over every LED light I could find sans the clock (which dims in the darkness thank goodness). It's amazing just how sensitive your eyes are to light pollution at night. Every power bar I have has a glowing light of some kind. One even has two. I have a wireless extender that has several LEDs on it. Then there's the TV, the TV cable box, a heater...everything got the electrical tape band aid treatment. I even put a black screen wipe over my cell phone in it's charger cradle that likes to let me know it's charged by beaming me in the face with green light. Tablets get charged with their cases closed and the laptop charger goes face down into the carpet. When I charge my electric shaver or toothbrush, they get turned upside down to shine their light into themselves. Made a HUGE difference to the point where I have to feel my way around if I shut off the lights too soon.

        I've had to get obsessive compulsive about this just so I can get a decent sleep...but it's worth it!

        • It's amazing just how sensitive your eyes are to light pollution at night.

          Not exactly surprising - so are astronomical telescopes.

        • by plover ( 150551 )

          I hear you! Bedrooms should not be lit at night. Black tape and an Xacto knife works great for blocking indicator lights without being too ugly.

          But I've had a couple of weird issues with the electronics in our bedroom. Our garage door indicator has a bright green light to indicate the door is closed, and just taping the LED wasn't enough, as the case was semi translucent. I lined the inside of the case with aluminum duct tape to solve that problem. Fortunately, the red LED is a separate component, so i

          • by Mal-2 ( 675116 )

            And the cradle itself is stupidly sculpted to match the remote, causing a different problem. Instead of a mechanically positive connection, the curved cradle supports the remote at precisely its center of gravity, allowing it to teeter, and every time it teeters it slips on and off the tiny charging contacts.

            It's time for more electrical tape, this time within the cradle, at the end opposite the contacts. This way the remote will be tipped toward the contacts instead of rocking back and forth. It may take more than one layer of tape to do this, and the aluminum tape you used on the garage door may be better still.

          • And the cradle itself is stupidly sculpted to match the remote, causing a different problem.

            YES, this is confirmed to be of extraterrestrial origin.

            At the dawn of the 21st century our LSI chip and circuit board designs were very advanced but rectilinear in the traditional sense. Ergonomics was understood to be about proper posture and comfortable wrist action.

            Then a spaceship landed, probably in the Akihabara district of Tokyo. Traveling buyers and consumer electronics engineers were lured into tiny stalls with the promise of "see video with new product idea" where they were subjected to various e

        • I just purchased a new alarm clock and it bright enough that I could read by it's light. Since I keep it close to my bed I had to put two layers of tinted plastic over the display in order to sleep with it on the lowest setting. now it's almost impossible to read the time during the day.
        • Don't take this the wrong way, but...

          What's with all the comments about not being able to sleep at night, are you guys sleeping in the same room as your pile of electronics or what? Granted, my bedroom has a few things that have LED's on them, like the TV Receiver, and clock, but reading through this thread, it sounds like everyone here sleeps in the same room with their whole home theater equipment, laptops, desktops, pile of cell phones/tablets, garage door openers, and microwaves! WTH? Do all of yo
          • by Cyberax ( 705495 )
            Try sleeping without lights. It really helps to improve quality of sleep, you start noticing it in several weeks. Your eyes have photosensitive cells that affect the circadian rhythm and they work even when your eyes are closed.
        • Focus on the blue ones. Blue light interacets with serotonin/melatonin and can delay/prevent sleep.

          Hell, one of my external hard drives has a power light that is quite visible through duct tape.

    • Yeah, no kidding. I'm a part time sound engineer and DJ, and the "Power" indicator on my mixing board is an ungodly bright blue light. I usually end up setting something on top of it to keep it from blinding me in an otherwise-typically-low-light environment.

      • by Jim3535 ( 903233 ) on Friday September 26, 2014 @02:16PM (#48005029)
        There is a company that makes lightdims, which are like tinting stickers that you can put over LEDs to dim them (block some of the light). They come in different strengths, even blackout.

        I use them on the computers and other electronics in my bedroom since the LEDs collectively put out so much light it's hard to sleep.
        • Reminds me of a scene I saw as a kid watching America's Funniest Home Videos, where Bob Saget "fixed" the omnipresent VCR clock which invariably flashes "12:00", by sticking a piece of masking tape over it.
        • by SeaFox ( 739806 )

          Thank you for the tip.

          Just rebuilt my NAS in a different case, and while I have no qualms about covering the power LED with electrical tape and blocking it out completely, I'd like the hard disk LED to be visible but dimmer so I can still see it to monitor it for heavy disk activity, but not have it bright at night.

      • by jellomizer ( 103300 ) on Friday September 26, 2014 @02:36PM (#48005199)

        In Low light environments you really need red LED's
        Sure Red LEDs are old. But for low lights your eyes don't adjust as much to red lights.

        • Isn't human vision system (including perception) self adjusting to different expected color temperatures at different light levels? I wouldn't be surprised if blue at night were murderous if our eyes are indeed compenssting by adjusting towards higher blue sensitivity near dawn or dusk when there's not much blue in the incident light.
          • by Dogtanian ( 588974 ) on Friday September 26, 2014 @05:24PM (#48006237) Homepage

            I wouldn't be surprised if blue at night were murderous if our eyes are indeed compenssting by adjusting towards higher blue sensitivity near dawn or dusk when there's not much blue in the incident light.

            If you came to that conclusion on your own, I'd congratulate you on (possibly) being extremely perceptive, but also surprised that you weren't aware that it's already been widely reported in the past few years that, yes, blue light is apparently very bad news from the point of view of being sleep-inhibiting:-

            Example story [washingtonpost.com]

            Blue light presumably being far more of an issue in recent years due to (a) the increase in use of electronics and (b) the blue LED fad. (*)

            I've seen an alarm clock with blue numbers- presumably because blue LEDs are cool!!!!!!11111- which struck me as an absolutely horrible idea. As did a ******* blue-coloured baby nightlight (because even baby deserves to be kept awake by fashionable blue LEDs. Sheesh.)

            (*) FWIW, the blue LED fad seems to have died down in the past couple of years, and white LEDs are the new hotness. Which is a good thing from an aesthetic point of view (**) but I suspect those white LEDs still contain a lot of blue. Especially the more bluish-white ones which may well just be blue ones with phosphor coating (as some "white" LEDs apparently are).

            (**) Nothing against blue LEDs as a concept, it's great that they were invented. What I hate is their gratuitous use- or rather, misuse- in consumer goods, both because they're overused and the novelty wore off long ago, but also because they're far more distracting in context than red ones ever were.

            • Not just some - all. White LEDs *are* blue LEDs with a phosphor coating; the amount of phosphor determines whether it is a "cool white" or "warm white" style LED.

              You can also make "white" light by running all three components of an RGB LED at max, but nobody does that because it is way more expensive in terms of dollars and in terms of lumens-per-watt.

              • I thought some were UV LEDs with a phosphor coating which gives better color spectrum but lower efficiency.

        • That's why when we put back lit keyboards in for the radiologists, we got red ones that are adjustable brightness.

        • by liquid_schwartz ( 530085 ) on Friday September 26, 2014 @03:56PM (#48005699)
          Really what you're getting at is that red light doesn't destroy scotopic vision (ie night adapted vision) because the rod cells respond very little to red light. Notice I said respond very little, a bright enough red light will still have an impact. Using somewhat dim red light allows you to see things yet still retain your night vision. Even a brief moment of other light colors (ie white, blue, etc) will result in losing the night adapted vision which can take up to 30 minutes to fully recover.
          • This is why the miltary (at least used to) use red lights inside vehicles when night operations were getting ready. The guys could see what they were doing and then when they exited the vehicle into the dark, their night vision wasn't totally messed up. Also, the old military style flashlights used to have a red-lense for them so you can use it to read maps at night without destroying your night vision.

            Anyone remember in the movie Predator, at the beginning when they are all in the helicopter, preparin
    • by gstoddart ( 321705 ) on Friday September 26, 2014 @01:55PM (#48004881) Homepage

      Your equipment will now have 57% brighter indicator LEDs on the front

      LOL ... must ... not ... make ... joke ... about ... "equipment".

      Suddenly I'm thinking of the neon lights under cars, and wondering if this won't be the next big thing in body modification.

      • by Nethead ( 1563 )

        And the ladies will get "landing lights" down their legs. Just remember, no means no, and no touch and go allowed. Circle the strip until you get clearance, or find another field.

    • Why the hell did the industry move away from using red LEDs for power indicators?

      It really is the best color for that. It's clearly visible, doesn't mess up dark adaptation, and red LEDs are the cheapest.

      • But blue is brighter. It should be important for you to know your devices are on!

        Seriously, I have a netgear router that has 1 blue led for every wifi antenna and they dance based on which one just picked up a packet. It took me two years of having it blocked with tape and paper towels before I discovered the thing had a feature to turn them off.

        • Blue LEDs are vile! Can't stand them on electronics or anywhere in fact. The brightness is way up, and is a major distraction from even a far distance. Hopefully the fad of using them will pass.

          • I had a Sonata CPU case with a pair of blinding blue LEDs, and those buggers were annoying; but the little notification LED on a Samsung Galaxy S4 isn't bad.
            The thing that astounds me is that OLEDs and LEDs can be so much brighter still. I have to admit, 15 years ago, my thoughts and predictions about LEDs in general couldn't have been more wrong; I figured they were a dead end, and as good as they were going to get. Then LED TVs came out, and high output versions like those made by Cree, and it was a
        • by sconeu ( 64226 )

          Apparently, it's more important to know when they're of.

          My TV, my DVD player, and my Blu-Ray player all have an LED that lights up when the device is OFF, and goes dark when the device is ON.

      • by tlhIngan ( 30335 ) <[slashdot] [at] [worf.net]> on Friday September 26, 2014 @02:56PM (#48005341)

        Why the hell did the industry move away from using red LEDs for power indicators?

        Because people wanted to be "trendy" and "futuristic" and thus started putting blue LEDs (which only came out two decades ago) in their equipment. Red was dull and boring (being done way back in the 60s) as was yellow. Green as we know it today (rather than a sickly yellow-puke-green) was a mid-90's invention. Blue LEDs came out in the mid-late 90s.

        So since they were so recent and popular, people stuck them on everything to show they were progressive.

        • Actually, I think in Europe they're particularly picky about what kinds of indicators can be red.

          OK, fine. Green's good if the item in question isn't capable of going Terminator on you when powered up. I like yellow and orange and even white. Black LEDs are kind of hard to read though.

          Blue's OK in its place, but please, I DON'T need to see my bones projected on the wall behind me!

      • Red, orange, and green are acceptable depending on the purpose to allow choice. If there's multistate you can have green for good, red for fault. Old laptops used to use green to mean powered on ( or charging), and red to mean low battery, or bad power supply voltage. Old desktops would be green for power, orange for turbo, and red for HDD. For for a simple pilot light red is the cheapest (and I agree the best). Thankfully all the blue LEDs have significantly faded over the past 7 years since I bought my la

        • Red-Yellow-Green is bad human factors practice because of red-green color blindness. For people of western European decent, about 1 in 10 males are red-green color blind. Other populations have different statistics. Only 1% of Eskimo males are color blind. Approximately 2.9% of boys from Saudi Arabia and 3.7% from India were found to have deficient color vision.

          Web designers almost never take this into account. For data display, red-yellow-green is common, as is the "spectrum" blue-cyan-green-yellow-red r

    • The immediate commercial demand is in the displays of portable electronics, where this technology will decrease power consumption and deliver better contrast, especially in daylight.

    • Simple fix: add a pot to the dropping resistor part of the circuit.

      • Another simple fix: Add a current limiter to the die.

        Well, it's simple if you're the LED manufacturer!

        I know it sounds strange, making devices that are deliberately set to under-perform. but we're plagued with too much of a good thing!

    • I bought a dishwasher and found it came with a free night light.

  • by i kan reed ( 749298 ) on Friday September 26, 2014 @01:43PM (#48004791) Homepage Journal

    All they've changed is how they contain it to limit the amount of light lose to absorption. I mean, to the user of LEDs the distinction is pretty irrelevant, but if you were wondering how you could improve on such a fundamental electrical component, that's how.

  • by WillAffleckUW ( 858324 ) on Friday September 26, 2014 @01:44PM (#48004799) Homepage Journal

    Just saying.

    The main barrier to large scale consumer and commercial adoption of LEDs is cost per unit.

    That said, good news!

    • by Greyfox ( 87712 )
      I don't mind paying $20 for a light bulb I'll probably never have to replace again. I have some high hanging lights that require a step ladder and some OSHA violations to replace. I'll be happy to slap a LED in there next time they burn out, and probably never have to deal with it again.
      • by afidel ( 530433 )

        I don't mind paying $20 for a light bulb I'll probably never have to replace again
        OLED's are nowhere near that, OLEDs are expensive to manufacture, and the most common current chemistry results in a blue half life of 15-20k hours, or 5-7 years at 8 hours per day. With traditional LEDs the bulb lifespan isn't dominated by the LEDs themselves, but rather by the heat sensitive electrolytic capacitor (this is why in the real world LED bulbs have no advantage over CFLs, they both fail due to capacitor failure).

        • Which is why when installing screw in LEDs or CFLs, I only put them in open, base down (or sideways if I must) fixtures. It's amazing how few ceiling fixtures there are that meet these criteria. With CFLs I've had very few premature failures, where the people that complain about them lasting less than an incandescent I assume put them in the worst applications possible (enclosed, base up, on a dimmer when not rated, short cycled).

          Ideal for LED is an entire replacement fixture, where thermal management can b

          • This is my favorite non dimmable lightbulb.

            http://www.amazon.com/G7-Power... [amazon.com]

            It goes in and out of availability tho.

            It's reasonably priced when available ($12).

            Did some searching and ....

            It looks like it's been replaced by this
            http://g7power.com/g7-power-tr... [g7power.com]

            which is now dimmable dimmable.

            The thing that is unique about these bulbs is that they are *indistinguishable* from traditional incandescent bulbs. The original bulbs were 65 watt which was noticably better for my older eyes. Sadly the newer bulbs ar

      • I don't mind paying $20 for a light bulb I'll probably never have to replace again.

        With CFLs we were promised 10 times the life of incandescents, some live up to that but many don't even from supposedly reputable brands. Fully enclosed fitings with the lampholder above the bulb seem to be particular death to CFLs.

        Yes in theory an LED bulb can last even longer than a CFL but i'd be very reluctant to pay such high bulb prices on a relatively unproven and easy to screw up (AIUI high power LEDS need careful cooling design and drive circuit failure is also an issue as it is with CFLs) tech.

  • Woo hoo!! (Score:5, Funny)

    by gstoddart ( 321705 ) on Friday September 26, 2014 @01:49PM (#48004829) Homepage

    Can't wait for my 57% brighter Christmas tree.

    You'll see that sucker from space.

    • You'll see that sucker from space.

      Indeed you will. With the spread of super bright white LED street lights, the light pollution situation will get exponentially worse. Amateur astronomy has been on rocky ground for some time. These lights are the death knell. Real pity.

      • by itzly ( 3699663 )
        Not likely. Modern LED fixtures are better designed to aim the light down to the street, they are often dimmable so they can be dimmed down during the really dark hours.
        • Unfortunately it is not only likely that LEDs are worse but the problem is already playing itself out. I've seen it. In my area I've noticed and increase in white light light pollution over the last five years. The IDA, which is a body involved in attempting to reduce light pollution, is concerned. There are multiple reasons why LEDs are becoming problematic.

          Light scatters off the ground too and back into the sky. If the fixture is bright enough then any gains from it being more directional are lost by t

    • Santa's gonna slap you with a lawsuit for blinding his reindeer.

  • by Steve Newall ( 24926 ) on Friday September 26, 2014 @01:58PM (#48004899)
    The article explains that the light extraction is increased from 3% to 60%. This is a factor of 20 increase in light output. So compared to a "normal" LED, this new technology is actually 2000% more efficient.
    • by tomhath ( 637240 ) on Friday September 26, 2014 @02:19PM (#48005055)
      The 57% improvement was on top of existing improvements like adding a reflector. This brought it up from something like 38% to 60%.
      • by Twinbee ( 767046 )
        If you dig deeper into the math, it's a 55% improvement rather than 57%. That sounds like a trivial difference I know, but the logic is important for future comparisons. Let me explain.

        Presume the new efficiency was 99% and the old efficiency was 38%. Naively, that sounds like 2.6x better. However, it's far more constructive to look at it in terms of how close it comes to 100%. So really, the formula is (100 - 38) ÷ (100 - 99) which means it's not 2.6x more efficient, but 62x more efficient. To get
  • by Anonymous Coward on Friday September 26, 2014 @02:02PM (#48004925)

    There's a big difference between "LEDs" and "Organic LEDs". To the best of my knowledge, organic LEDs aren't used for "lighting".

  • ya know I loved it when they first invented this whole new bright LED technology back 5 or so years ago... I was so impressed by the street lights, and anything else that used them - I could easily tell the new LEDs from the old ones. But when my old clock radio died, i went to wal mart and bought a cheapo 20 buck LED lit digital alarm clock with cool looking blue light. But the fucking thing is Soooo bright that at night it's like having the sun in my bedroom with me. I was thinking about sticking some
  • by necro81 ( 917438 ) on Friday September 26, 2014 @02:26PM (#48005097) Journal
    IEEE Spectrum also has coverage [ieee.org], along with an excellent technical explanation.
  • by MindPrison ( 864299 ) on Friday September 26, 2014 @02:28PM (#48005117) Journal
    ...because it doesn't pay very well to sell you something that'll last forever, whether it's an Oled screen or LED bulb.

    It's no coincidence that the CFLs die off after 1-2 years albeit they're supposed to last 10-20 years with normal usage. My first Philips 11w CFLs that I bought 20 years ago, still glows like mad and simply refuse to die. That is back when the CFLs was new, and cost like 40 bucks just for ONE bulb, but hey...it's actually worth the money, it still is my best bulb.

    With LED's, it's a walk in the park for the industry to make them last less, all you need to do for your LED to last less than specified, is to OVERDRIVE them just a little, a little higher current and the LED's will die rapidly, they should be able to make the new LED lamps last just out the warranty period (that in most countries AFAIK is around 3-6 months), or cheap enough to avoid the warranty altogether.

    There is nothing wrong with the LED's themselves, (we're talking the components...DIODES...not the whole circuit with drivers and all), I ordered strong RGB leds from China many MANY years ago, they're still glowing on my homemade alarm-systems so strong that I can use them as night-lights, yes...4 years later 24H day use...they still glow enough to lit up an entire room. And I just used Ohms law + 1% resistor values to calculate the right resistor value for my circuits. You can pretty much BET the manufacturers will "miscalculate" these values, or make the drivers for the stronger LED's last MUCH less in order to keep pumping out new ones for the consumers to waste and waste.

    I'd rather pay a proper price for my LED lamps - and keep our environment safe from this mad overproduction that now has escalated totally out of hands. :(
    • by smellsofbikes ( 890263 ) on Friday September 26, 2014 @03:30PM (#48005553) Journal

      ...because it doesn't pay very well to sell you something that'll last forever, whether it's an Oled screen or LED bulb.

      With LED's, it's a walk in the park for the industry to make them last less, all you need to do for your LED to last less than specified, is to OVERDRIVE them just a little, a little higher current and the LED's will die rapidly, they should be able to make the new LED lamps last just out the warranty period (that in most countries AFAIK is around 3-6 months), or cheap enough to avoid the warranty altogether.

      There is nothing wrong with the LED's themselves, (we're talking the components...DIODES...not the whole circuit with drivers and all), I ordered strong RGB leds from China many MANY years ago, they're still glowing on my homemade alarm-systems so strong that I can use them as night-lights, yes...4 years later 24H day use...they still glow enough to lit up an entire room. And I just used Ohms law + 1% resistor values to calculate the right resistor value for my circuits. You can pretty much BET the manufacturers will "miscalculate" these values, or make the drivers for the stronger LED's last MUCH less in order to keep pumping out new ones for the consumers to waste and waste.

      I'd rather pay a proper price for my LED lamps - and keep our environment safe from this mad overproduction that now has escalated totally out of hands. :(

      Buy Crees. I work in LED driver design, and Cree, who I don't work for but I work with, seem to do a good job of making sure their LED's don't get associated with junk. Philips similarly, to a lesser extent.
      So, from the inside, it's not that manufacturers generally scrimp on bulbs to make them fail faster so they can sell more. The economics of light bulbs don't support that business model. It's that people are crazy reluctant to pay $15 for a lightbulb when an incandescent costs under $1. So manufacturers engage in heavy-duty Muntzing [wikipedia.org] until the bulb will just barely run, and they've cut the BOM by $1.45... and then it dies quickly. It's called value engineering, which as far as I'm concerned means removing all the value. They use cheap input filter caps, and scrimp on those, and they use cheap heatsinking which is poorly thermally coupled to the LED's, so the LED's operate at a high junction temperature and don't live very long.
      Incandescents have visual inertia, for lack of a better term: if you pour a 30 hz square wave into one, it'll still look pretty good. LED's react in nanoseconds. Crappy dirty line power combined with dimming makes for a really demanding design, and designers and apps engineers have to work with a huge variation in dimmer designs. Consumers don't see any of that: all they see is "no way I'm paying $25 for a lightbulb" so they buy the crap ones and then get infuriated with them because they're visibly flickering and only last five times as long as an incandescent. I can't really blame them, either. There are really good lightbulbs out there. They're expensive. They should last 50,000 hours. But it's hard to tell what you're getting if you're not in on the design.

      • You're very right.

        I've reverse engineered enough cheap knockoffs in my life to verify your story. Everything from cheap PSU's with barely more than a Triac inside, to USB-hubs, cheap lasers, cheap communications transceivers (a chip & an half).

        But yeah, we really DO get what we pay for. So dear consumers who are reading this, please protest by not settling for the crappy stuff. Buy quality and prove to the world that's what we want! I've been 30+ years into electronics (many as a service tech). We
        • But yeah, we really DO get what we pay for. So dear consumers who are reading this, please protest by not settling for the crappy stuff. Buy quality and prove to the world that's what we want! I've been 30+ years into electronics (many as a service tech). We've got a heck of a job in front of us, but I honestly believe the public will tire of the crappy products, hopefully NOT before it's too late.

          The big open question for our time: how do we tell if stuff is quality?
          Stuff that has the same manufacturer's SKU number, you open it up and it has all different guts than last year's because they've changed subcontractors.
          They come out with a new version every four months, so by the time reviews are up on one you can't buy that model anymore.
          Manufacturers have adopted influenza's tactic: change so fast that the system can't keep up with you and fight your badness.
          Since us consumers need to buy stuff, we ha

    • by Whibla ( 210729 )

      ...because it doesn't pay very well to sell you something that'll last forever, whether it's an Oled screen or LED bulb.

      ...and the LED's will die rapidly, they should be able to make the new LED lamps last just out the warranty period (that in most countries AFAIK is around 3-6 months), or cheap enough to avoid the warranty altogether...

      I'd rather pay a proper price for my LED lamps - and keep our environment safe from this mad overproduction that now has escalated totally out of hands. :(

      I'm not sure how you're arriving at conclusion regarding 'most countries', given that much of the first / second world has, by and large, harmonised trade agreements and importing / exporting between them is realtively trivial. Certainly where I live (the UK), and the majority of Europe, the warranty period for the LED bulbs I purchased is 16 years, a mere factor of 30+ times the figure you give. Whether I'll still be able to find the receipts in x years time if one of them fails is another issue, let alone

  • Maybe someone who works in new led technology can answer two questions:

    Does / might this apply to to LED light bulbs as opposed to screens?
    TFA refers to screens.

    If so, care to take a guess as to how long it will take for this to be on store shelves?

  • by Animats ( 122034 ) on Friday September 26, 2014 @02:31PM (#48005151) Homepage

    The real breakthrough in LED lighting is getting rid of electrolytic capacitors in the power supply. Those are currently the components with the shortest life. See "Elimination of an Electrolytic Capacitor in AC/DC Light-Emitting Diode (LED) Driver With High Input Power Factor and Constant Output Current" [hub.hku.hk] Variations on that technology are now going into production LED lighting units. This should push unit lifetimes up from 20,000 hours to that of the LEDs, 40,000 or so. (Provided the quality of the LEDs doesn't slip.)

  • So when will I get my sunlight-visible iPad and Macbook Pro (17-inch, please)?

  • The picture in the first article shows "bumps" added to the outside of the material. Is this kinda like how a diffraction grating works? Where the spacing between those "bumps" matches the wavelength of the light?

  • I don't care about 57% efficiency I care about lighting that is not gross or otherwise as annoying as heck.

    Bright blue leds.. can't stand them around here they end up being disconnected or gouged out in short order.

    LED street lights make me cringe every time I drive under them. Say what you will about the yellow spike that are sodium lights they are much easier on the eyes especially at night. Streets are not supposed to resemble stadiums and leds are not more efficient than LPS.

    Christmas LED lights are

  • "they still fall behind more conventional forms of lighting in terms of brightness."

    The most advanced consumer LEDs have a higher luminous efficacy than HID, fluorescent, and incandescent lights. They have for several years now.

    The luminous flux of LEDs is good as well. Although the total power of LEDs tapers off after around 30W, manufacturers use large arrays of the more efficient low power LEDs and achieve incredibly high luminous flux. E.g. Cree sells a flood light that is 850W and outputs 75000 lumens.

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