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Breakthrough In LED Construction Increases Efficiency By 57 Percent
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.
Your equipment will now have 57% brighter indicator LEDs on the front to burn your retinas at night!
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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.
Just saying.
The main barrier to large scale consumer and commercial adoption of LEDs is cost per unit.
That said, good news!
-- Tigger warning: This post may contain tiggers! --
Can't wait for my 57% brighter Christmas tree.
You'll see that sucker from space.
Lost at C:>. Found at C.
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.
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 semi transparent plastic over it, but I couldn't really find anything suitable. so, i just throw clothes on top of it and it becomes useless unless i care enough about the time to dig it up.
Even if they are already bright enough, you can still trade brightness for efficiency and get increased battery life.
John
Any further development to increase longevity, efficiency, affordability will be bashed by The Great Lightbulb Conspiracy.
Linux is for people who don't mind RTFM.
IEEE Spectrum also has coverage, along with an excellent technical explanation.
...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.
What this world is coming to - is for you and me to decide.
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?
Try running a new smartphone on a battery of the same size from 10 years ago, then come back and tell us they haven't improved batteries.
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" 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.)
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.
So when will I get my sunlight-visible iPad and Macbook Pro (17-inch, please)?
The proper way to do this, for new build at least, is to have a separate low voltage lighting circuit. Use 1 high quality transformer and decent polypropylene capacitors, then the only component you need in the bulb is the LED (possibly also a heatsink and resistor). That should last for ages and centralises the rectification and smoothing so that cheap and nasty components can be avoided and the whole thing can be user serviceable. For a typical 3-bed house (say 10 rooms including hallways) that's about 120W assuming a 12W LED bulb provides the same output as a 60W incandescent (about right IME). A 120VA transformer is chicken feed - maybe ã30-40 - and 100uF PP motor run capacitors go for about the same. Even allowing some contingency, the cost is epsilon compared with the cost of a new house.
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 think that most people would rather have 2x battery life or 2x brighter light in their flashlight, rather than it lasting twice as long, considering that I'm yet to see IC of flashlight to die on me.
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 puke-ish .. faint dull sickening flickering half wave monstrosities. I used to love going outside to look at all the nice warm Christmas lights now we drive by these hollow ghosts of years past and it is depressing.
White LEDs in displays have shitty CRI, can't be dimmed at night because PWM flicker would fall below flicker fusion threshold and screening the panel kills contrast ratio.. They can't even achieve sRGB coverage. Other LED based arrangements such as RG-B are however quite good.
Cheap LED screw in light bulbs with white LEDs are sickening... however slightly more expensive version with phosphors are just as good as CFLs without the startup lag.
LED flashlights look like shit but batteries last forever so they get a pass.
OLED displays are unreliable compared with CRT and TFT panels suffering from element failure and CRT erra phosphor burnin.
I don't care about efficiency... I care about quality products I would actually want to purchase that don't compromise and take shortcuts at my expense.
TFA is like announcing the 50% efficient PV cell breakthrough that costs so much nobody but NASA would ever use it... it isn't the point ... the breakthrough is in addressing consumer demands and LEDs have a LOOONG way to go in my view.
While it seems like a good idea to have a low voltage circuit, there some unfortunate realities that have to be taken into consideration. Mainly you need much thicker wiring to keep your resistive losses low. It's actually cheaper to have a transformer in the light fixture itself than it is to run heavy guage wire everywhere. https://en.wikipedia.org/wiki/...
So lets pretend that we've just completed writing this code, as opposed to having just completed sabotaging it -Altera
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.
whose green power indicator only seems to be there to let you know that the device is plugged in. On or off, the damn thing is lit.
How can I tell whether a given LED bulb from the shop has this tech? What companies currently use this tech?
Why OpalCalc is the best Windows calc
"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.
For domestic use, LEDs have higher luminous flux than competing lighting techniques.
What about 3-phase power for lighting? When you full wave rectify 3-ph you don't get the 0 volt valleys in the wave. Of course, we're not going to re-wire all our houses for that.
"However, despite their luminous outputs having increased steadily over that time, they still fall behind more conventional forms of lighting in terms of brightness."
Bullshit. We're pumping 300+ lumens per watt, 5150K, 350mA drive current, 85C operating temperature.
There's not one goddamned thing on this planet that can touch an LED, now. The sun only hits ~93 lumens per watt, once you get all the really complicated math down.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
"Even high CRI (color rendering index) LED lighting has a nasty spike in the blue region."
Would you like to know why?
Because that blue led is now so damned efficient and the remote phosphor tech doubly so.
Going by input power/output power, the blue LED is almost 65%-70% efficient. It would have to be to get Cree's current 5150K LED at 300+ lumens per watt.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Man, you're full of shit. Every LED light I've owned has gone well over that.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Damn, I'm not a doctor so I don't know any of that is correct, but I have got to say, that is the best explanation of what I'm sure is a highly complicated subject that I've read in ages. Maybe it's because I'm an EE so I'm familiar with the terms you substituted. Curiously, have you considered writing a medical book in that style? Perhaps call it Medical Engineering for Engineers or some such! +1
"The real breakthrough in LED lighting is getting rid of electrolytic capacitors in the power supply."
That's nothing.
I just did away with the power supply entirely.
Give me a good remote phosphor with a fair amount of persistence, no more flicker.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Yes, because allowing my stuff to consume a tiny fraction of their normal draw is the same as "rolling coal."
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
Do you have a link that points to this analysis in residential housing? I calculated I could wire my house (9 rooms) with 0.5% loss for $60 bucks at a very sloppy 200 ft in 14g wire.