Organic LED Could Replace Light Bulbs?

egrinake writes to mention a BBC article about a 'natural' replacement for lightbulbs. From the article: "The organic light-emitting diode (OLED) emits a brilliant white light when attached to an electricity supply. The material, described in the journal Nature, can be printed in wafer thin sheets that could transform walls, ceilings or even furniture into lights. The OLEDs do not heat up like today's light bulbs and so are far more energy efficient and should last longer."

Comments

Good Idea...

[PC-PHIX]

...but a wafer thin sheet of organic material shining above a cartoon character's head is never going to look as good...!

Re:Good Idea...

[Qzukk]

How many biomechanical engineers does it take to replace a wafer-thin oled sheet?

Re:Good Idea...

[Surt]

This is pretty funny, but in reality I fully expect that a lightbulb over the head will always be symbolic of idea, it's just that eventually we won't know what a lightbulb is. It'll just be an idea over the head, and no one will know why it looks like that.

Obvious Safety Application:

[Sir Unimaginative]

Drop a couple AAs into a pouch in a jacket or something, wire it up to strips of this: Suddenly drivers etc. can see you at night. I wonder if there's any feasible way to do this in a torch format....

Re:Obvious Safety Application:

[Detritus]

Some drivers still wouldn't see you, even if you soaked your clothes in gasoline and set them on fire.

Re:Obvious Safety Application:

[cloudmaster]

I think most drivers would notice you setting attempting to set them on fire, whether your clothes wre soaked in gasoline or not. :)

In clothes

[Bombula]

Once they get this stuff stitched into clothing, it's going to be just about unbearable. As if all the marketing crap of t-shirts wasn't bad enough already, what with our entire culture expressing individuality by paying corporations for the privalege of advertising their products on our bodies, now people are actually going to be lit up like downtown Tokyo. Fan-fuckin-tastic...

Well, I suppose the Tron Guy is going to have a field day with this stuff, so it's not all gloom and doom...

Re:In clothes

[Dibblah]

Please. Don't do that. At least there's only one tubgirl pic.

Everyone will steal them for the platinum

[mattr]

Thank google for google..
It's a story of USC and UDC (Universal Display Corp. near Princeton U)
Though it seems they need to make sure it doesn't get wet, and looks like a target for thieves who want the platinum or iridium in every molecule..
Interesting that one article says current incadescents are 15 lumens/watt (true?) while OLED is now at 20 with potentially 60 l/w in near future. I thought those led/dry cell driven pocket torches produced 30 lumens though..
google keys: Professor Mark Thompson of the University of Southern California oled

Re:Everyone will steal them for the platinum

[Plunky]

I thought those led/dry cell driven pocket torches produced 30 lumens though..

as far as I can tell, that is marketing bullshit.

I have a LED headlight for my bicycle and while it is very intense when its pointing right at you, it has very poor illumination capability when compared to an incandescent headlight. The light is very directional so when they say 'X lumens' it generally means they measured the output in the beam segment rather than the the whole sphere.

For town riding, such a headlight is fine. You arent using it for its illumination, you really only want a light so cars can see you, and if you are riding into oncoming traffic at night chances are you are a fool. The rear light is generally more important. In the country where streetlighting is non existent, the LED is barely adequate and you need an incandescent bulb.

I can't be bothered to google for references to back my shaky claims up, its just a personal anecdote.

Finally, a use for IPv6

[tk2x]

I have 10,000 light sources in my house... and I want to customize lighting scenes for every mood. Each OLED has its own IPv6 address, and I have a touch screen where I can paint different color lights.

Hmm, interesting possibilities...

Re:Finally, a use for IPv6

[Anonymous Coward]

So many possibilities... and you'd just end up drawing boobs and penises on it.

Re:stupid energy noob question

[meringuoid]

It seems to me the more heat I produce from my bulb/processor, the less my temperature regulator will pull energy from my heating system (based on gas, which is becoming more expensive). What's wrong with this way of thinking?

There's an extra layer of inefficiency. If you heat your house by burning gas, you get nearly perfect efficiency: almost every joule of heat liberated by the chemical reaction goes into your house, with a relatively small amount of waste heat going up the chimney; modern boilers are very efficient indeed at getting every bit of heat they can.

If, OTOH, you heat your house by electric current - i.e. by the waste heat from your electrical devices - then somewhere in the world there's a power plant burning gas on your behalf. That plant converts gas to heat at higher efficiency than your boiler, but then wastes energy in the conversion to electricity, and then even more is lost in transmission to your home.

So, if you switch to more economical lighting, your boiler will have to burn a little extra gas because you're no longer getting the heating effect of old-fashioned incandescent lightbulbs. But that's more than offset at the power plant, where they have to burn less gas because you're consuming less electricity.

economy

[boldi]

There's only one question every time. How much light/W does it produce (lm/W)? And what is the price for the 'OLED bulb'.

And... do not compare it to traditional light bulbs. Traditional light bulbs are dead.

Of course, LEDs have achieved a lot in producing more and more light, but currently it is some 10s or 100s fold differends between the price of the
fluorescent light sources and a LED based one, and the fluorescent light source (mostly) produces more light than the LED.

Yes, I hope that OLEDs will be the ones who can reach the barrier, but until that this article is very-very optimistic :)

check
(figure:)
http://europa.eu.int/comm/energy_transport/atlas/h tmlu/lightdintro2.html
articles:
http://europa.eu.int/comm/energy_transport/atlas/h tmlu/lightdintro.html
http://www.lumileds.com/pdfs/TP40_IESNA_July%20200 4_LED_Paper.pdf

100% efficient

[Anonymous Coward]

TFA speculates that these oleds could become 100% efficient. Maybe these people should go to work on the perpetual motion machine. I'd bet the farm that they can't achieve 100%. "In this family we obey the laws of thermodynamics." etc. etc.

Re:Quick, bury it!

[david.given]

What's the bet a few light globe manufacturers will get together, buy the rights and then put it away in the archives?

Because if they could do this, they'd have already done it for fluorescent tubes, which can be up to about 60% efficient (compared to 10% for incandescent bulbs)?

OLED vs LED

[minimum]

OLED's are nice for displays, but not enough lumen/watt efficiency for general illumination.
LED's are improving much faster - 100Lm/W from Nichia to hit market soon:
http://www.eetimes.com/news/latest/technology/show Article.jhtml?articleID=181503227/

Re:OLED vs LED

[Savantissimo]

I may be wrong here, but from what I remember from high school LEDs produce light by making an electrical arc over a _very_ short distance.

No, LEDs work by using a voltage to push charge carriers in a semiconductor diode above the "bandgap" of the diode (the energy level at which the diode starts to conduct, which is determined by the type of semiconductor material used).

One part of the diode has positive charge carriers, the other has negative charge carriers, like so: +V ---{ p | n }--- V- Because like charges repel, the positive voltage pushes the positive charge carriers to the p-n junction in the center and the negative voltage also pushes the negative charge carriers to the p-n junction. The energy released when the positive and negative charges combine in the p-n junction comes out as light of a frequency (color) determined by the bandgap voltage.

This is a quantum process: Energy = Planck's constant * frequency (or E = h*f, often written E=h*v - that's a nu, not a v).

Sparks require a voltage that is higher the farther apart the electrodes are, and the highest frequency light produced does depend on the voltage, but sparks produce broad rather than monochromatic spectra with energy emitted down to very low frequencies.

**
As an aside, one can measure Planck's constant using LEDs:

Since the energy per charge carrier is the voltage times the charge (Electron-volts, which can be converted to Joules by multiplying by the factor coulombs per electron, 1.6E-19) and the wavelength is known from the manufacturer's data sheets and can be converted to frequency by:

frequency(Hz, 1/s) = speed of light(3E8 m/s) divided by wavelength(m, usually listed in nm = 10E-9m), given LEDs of known frequencies one can measure Planck's constant.

h = E/f = [V*(1.6E-19 Coulombs)*(wavelength in nm)*(1E-9 m/nm)]/(3E8 m/s) or

h (in Joule-seconds) = 5.3E-37 giga-coulomb-seconds * voltage * wavelength in nm.

Other factors make this an inaccurately low measure - the voltage needed to light the LED is lower than E = hf would indicate. (Perhaps it's the high energy tail in the distribution of thermal electron energies?)

A potentially more accurate way to get h is to note that in E = h*f, when E is graphed against f, then h is the slope of the line. Variations in eye sensitivity and LED efficiency also introduce inaccuracies here, but green and orange LEDs seem to give a slope very close to the correct number.

(Also note that you need single-color diodes - the "yellow" diodes commonly found are really red+green in a single package.)

See CERNs page on Jules Hoult's high school lab lesson plan:
lab sudent worksheet
results results graph

Re:Quick, bury it!

[earthpig]

I remember somewhere around 10 years ago i started seeing 'paper' products in the grocery stores made from cotton. Paper towles, TP that sort of stuff. i thought cool an alternative to wood. Sometime after that NPR did a story on the people who started the company and they talked about how popular the products were and how they were looking to expand, things were looking great. Then like six months later the cotton paper products were no longer available, anywhere. My guess is that the paper product manufacturers got together bought the rights and mothballed the idea?

Re:Quick, bury it!

[Detritus]

Rag paper has been around for a very long time. US currency is printed on rag paper. Wood is a popular raw material for paper products because it is cheap. No conspiracies needed, it's just economics.

This article is crap.

[subreality]

Everything they're saying about OLEDs, people have said about regular LEDs for some time. Sure, they're efficient and cool, but they've never become a primary lighting source for a couple important reasons:

#1, they're too expensive. Compact fluorescents - which are are a 4x efficiency gain over incandescents - are only just starting to catch on now that they're under $2.

#2, the color rendering sucks. You know how old fluorescents used to made you look undead? LED's suck even more.

So, instead of addressing either of those hard issues, they give us an article full of: "The researchers believe that eventually", "Before this becomes a reality", "If that barrier can be overcome", etc. Thanks for the fluff.

Also, I'm not normally a grammar nazi, but for the love of god, 23 sentences:21 paragraphs is a ratio to be ashamed of.

Re:This article is crap.

[Davey McDave]

No no no.

First of all, PLEDs (that's POLYMER based light emitting diodes) are a liquid, so they can actually be printed using existing inkjet technology - it's incredibly cheap to manufacture because you don't need special equipment, just modify existing plants. Instead now of printing paper, you're printing lightbulbs/screens.

Secondly, each of these is minutely small. The emissive layer is LIQUID. The resolution is absolutely fantastic, just as good as liquid crystal.

Thirdly, LCD screens are dependant upon polarisation. You have a really strong backlight, you pass currents through the liquid crystal layer and it blocks out certain frequencies of light. No matter what you show on screen, whether it be completely black or completely white, it's consuming the same electricity, it's just that in one, the liquid crystal is letting you see it, in another it's not. Have you ever wondered why the screen gets its darkest ONLY when you turn it off? That's because the backlight gets turned off. OLEDs naturally produce the light from the off, and only use the energy required to make the frequency you need. Not only does this mean you get a more natural colour, you get REALLY good contrast because you can render black properly.

Forthly (I should really stop this list): because you can tailor make a film of OLED to produce a particular frequency of light, it WILL look natural. If you're asking why, think back to some basic physics - you remember that when an electron descends an energy level, it emits a particular frequency of light? The sun has a pattern of frequencies produced this way, but it's with hydrogen, which is quite hard to replicate, with say, neon and flourescant bulbs. With OLEDs it's easy to tailor make molecules that'll replicate the same frequency spectrum.

I had to do a presentation about OLEDs a few months ago mate: I know my salt.

Re:This article is crap.

[marcosdumay]

Your 4th point is simply wrong. The sun emits light as a dark body, and it is a very hot dark body. It is hard to emulate the sun light with LEDs because LEDs have a very narrow emission spectrum, and a dark body's emission is continuos. Also, because the sun is very hot, it emmits light at very hight frequencies (blue and violet), that are hard to abtain on LEDs.

Don't Get It Wet

[Anonymous Coward]

"Before this becomes a reality, the scientists need to work out a way to seal the OLEDs from moisture which can contaminate the sensitive material, causing it to no longer work."

If only they could put it into an airtight package, something small and convenient, maybe a ...bulb... of some kind.

Re:Quick, bury it!

[mjh]

A secret conspiracy to deprive the public of OLEDs makes a bunch of assumptions:

1. There is no patent protecting this invention... AND
2. The consumer demand for this invention will be high... BECAUSE
3. It can be effectively used as a substitute for normal lightbulbs ...AND
4. It's more cost effective than normal lightbulbs (e.g. initial cost + lifetime eneregy spend is less for OLEDs than normal lightbulbs)

IF all of those things are true, then let a bunch of lightbulb manufacturers conspire not to produce it! All it takes is one who's willing to produce it, who can then start reeping huge market share (to meet the assumed customer demand). Heck, it could be you. If all of the above things are true, then you could come in and make a killing on this thing even if every single lightbulb manufacturer chooses not to. And as soon as you do, every manufacturer who "conspired" not to produce this will be forced to in order to chase after those profits that you're getting.

If any one of those assumptions above is false, then it does not require a conspiracy to prevent widespread production of this product. The most likely assumption that's false is #4, but it could be any of them. In any case, if we don't see OLEDs dominating the lighting market, will you simply conclude that it was a secret conspiracy or that maybe one of your upfront assumptions was false? My recommendation would be to apply occam's razor.

$.02

Re:Quick, bury it!

[Anonymous Coward]

I work for an electronics company with a world leading lighting divsion, and I can tell you we're moving to solid state lighting (of which OLED is a form) as fast we can. It's clearly the way of the future.

Obviously we're worried somebody else will take away our lighting market share by bringing out the killer-led-app. However, there's no question of "buying up IP and sitting on it". This playing field is as open as it gets in the industry.

longevity of light bulbs

[doti]

Replace the light switch with a dimmer and your bulb will last MUCH longer, even if you always use it to max. That's because the kick the filament receives when turned on is aliviated. Even if you turn it to maximum very fast, it's still a lot slower then the switch. I used to buy replacement bulbs every now and then. Since I put dimmers all around the house, and that was five years ago, just two bulbs died.

Re:longevity of light bulbs

[doti]

If not, how do you explain that the bulb allways burn when you turn it on, and almost never while it's already lit for some time? Well, that's how it seems anyway. I am not a scientist, but it makes sense to me, AND it matches the fact I experienced in the last five years in my own house.

Re:Quick, bury it!

[hankwang]

bulb manufacturers don't use the same filament precicely because it lasts too long

It's much more down to earth: there's a simple relationship between light yield and lifetime (from wikipedia:

• Light output is approximately proportional to V^3.4
• Power consumption is approximately proportional to V^1.6
• Lifetime is approximately inversely proportional to V^16

More light for your watt means the bulb burns out more quickly. They are now tuned for 1000 hours, which -mind you- means about $10 in electricity during the lifetime. If you want to increase the lifetime, put it on a dimmer.

Actually what I see happening is

[Shivetya]

the same manufactures doing a couple of things.
1. Putting out all sorts of products using OLEDs, expanding beyond what we conceive of light being used for
2. Putting out specialty incadescents/flourescents that fill the gaps in the first

If anything this expands their market and an innovative company will take off. Not all lighted items need to provide illumination that is bright enough to read by. A lot can be done with highlights, accenting areas with different shades and such. Accent lighting will be a big, replacing LEDs that are currently trying to edge into that market. All the business uses will help as well. It would be far much easier to use these for instore billboards than the flourescent lit displays so common today.

Now another area is backgrounds. Better for business use than home, though some may use it in homes. Can't imagine my home looking like 1999's moonbase but I can see walls in certain types of businesses where the whole area is covered and changed in color for events and such.

Lighting products are not all about letting you see things, some exist to be seen

Yeah but

[jlebrech]

how many OLEDs does it take to replace a lightbulb.

Re:Quick, bury it!

[shawb]

Ahh... but a dimmer means the bulb is not running at it's most efficient point, and so you use more electricity per lumen.

Which gets us to the real reason light bulbs don't have drastically longer lives... tuning a light bulb so it has a longer life means that it has significantly lower energy efficiency. Those "long life" light bulbs you see in the supermarket usually end up costing you more in the long run. They do make some sense to use them in a situation where they are difficult or even dangerous to replace, but then you would be wise to consider compact flourescent as they last VASTLY longer and use significantly less energy. And that "bad light" and "flicker that makes people sick" is pretty much an artifact of the past. Newer tubes and bulbs have much cleaner light.

Re:stupid energy noob question

[Spock the Baptist]

There's an extra layer of inefficiency. If you heat your house by burning gas, you get nearly perfect efficiency: almost every joule of heat liberated by the chemical reaction goes into your house, with a relatively small amount of waste heat going up the chimney; modern boilers are very efficient indeed at getting every bit of heat they can.

The above statement assumes that you live in a place where heating is the main problem for indoor environmental control. I'd like to point out that for folks between the Tropics of Cancer & Capricorn or respectively just above, or below them heating is not the problem, cooling is.

Here in East Texas we're already running our air conditioners and it's only April. The reason for this is not that it's all that hot, but to dehumidify the air in our homes, offices, etc.. I've lived in Texas for all my 40 plus years. Normally we have more than ten days of 100 degree F. or greater being our daily high temperature. Late July, and all of August, plus the first half of September can produce some real scorchers. The use of high efficiency lighting, helps reduce the power consumption at home, office, etc. in two ways. First, it simply use less Joules to produce a given amount of lumens of light, second it reduces the amount of waste heat that the AC must deal with. So, you save on the cost per lumen of light, and you save on the cost of AC that is used to rid the indoor environment of the wast heat.

I've noticed that many of the post here on slashdot have a 'high latitude/left coast' bias on energy issues. Can't imagine why.

Re:People like sunlight

[rebelcool]

tungsten isnt close at all to sunlight. If you've noticed those newer "natural" light lightbulbs you get are just tungsten with a blue filter on it to cool the color temp down.

theres also many types of fluorescent bulbs. the film industry uses daylight balanced fluorescent quite a bit now because you can have a continuous light source without all the extra heat generated by the incadescents.

in any case, regardless of what the color spectrum is, it is easy to color filter a brilliant white light.