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The End Of The Light Bulb?

Zonk posted about 9 years ago | from the accidents-make-the-heart-grow-fonder dept.

Science 434

sdmonroe wrote to mention an MSNBC article discussing the likely eventual replacement of common light bulbs by LEDs. That replacement is likely to come quicker thanks to an accidental discovery announced this week. From the article: "Michael Bowers, a graduate student at Vanderbilt University, was just trying to make really small quantum dots, which are crystals generally only a few nanometers big. ... When you shine a light on quantum dots or apply electricity to them, they react by producing their own light, normally a bright, vibrant color. But when Bowers shined a laser on his batch of dots, something unexpected happened. 'I was surprised when a white glow covered the table,' Bowers said. 'The quantum dots were supposed to emit blue light, but instead they were giving off a beautiful white glow.'"

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Holy Shit! (0, Offtopic)

Asshat Canada (804093) | about 9 years ago | (#13852825)

Fuck YOU!

Something new for moths? (5, Funny)

xanadu113 (657977) | about 9 years ago | (#13852827)

Something new for moths to fly in to?

well, likely not. (5, Interesting)

way2trivial (601132) | about 9 years ago | (#13852867)

at my workplace, a hotel on the beach.

We had for many years yellow colored standard bulbs, as they don't attract bugs.

we started replacement with yello fluro twist bulbs, to save on electricity and replacement costs.

in research, it turns out, we can use white fluro-- as they only emit light in a very narrow spectrum of white light, unlike an ordinary filament bulb.. and the range they do emit light on, suitable for humans, does not attract bugs.

I'd guess these low power led lights also emit white light on a very narrow band....

Re:well, likely not. (0)

Anonymous Coward | about 9 years ago | (#13852898)

a narrow spectrum of white light? eh?

Re:well, likely not. (1)

advocate_one (662832) | about 9 years ago | (#13852938)

a real contradiction of terms there... ;) I'm convinced science education has gone down the tubes... and this is really basic stuff which should be done in junior school...

no, it is NOT a contradiciton (4, Informative)

way2trivial (601132) | about 9 years ago | (#13852976)

I can make white light by emitting everything from UV to IR

or I can combine a 3 beams each of a very precise wavelength of red green and blue, and end up with WHITE.

a narrow spectrum of white.
very perception based.. I may see it as pure white, you may be more sensitive to one of the three, and therefore see it as green or blue or red tinged.

a bug may not see it at all.

Re:well, likely not. (4, Informative)

way2trivial (601132) | about 9 years ago | (#13852953)

alright, it has the white light, and none of the 'rest' of the spectrum, which apparently attracts bugs.
but yes, a narrow spectrum of white, I found a good picture here []

roll down to where there are three bulb types listed.

note the incandescent bulb rolls up from blue to red
note the fluroscent has three spikes of blue, yellow and red

the missing bits, including the missing UV and IR at the ends, include whatever attract bugs.

so yes- a narrow band of white light......

Re:well, likely not. (5, Informative)

farquharsoncraig (711336) | about 9 years ago | (#13852962)

thank you.. (1)

way2trivial (601132) | about 9 years ago | (#13852988)

that was an excellent pic of the distribution.

so these would still attract insects, but provide a fuller light experience for humans as well, than fluro..

A return to white street light (3, Insightful)

Simonetta (207550) | about 9 years ago | (#13852958)

One of the unfortunate side effects of the 1970s was the replacement of all the soft white street light bulbs with orange-yellow sodium vapor bulbs. Sodium vapor bulbs use less energy. All the night lighting went from soothing soft white to light orange. Orange, as you may recall, is the color of madness.

    I've never liked yellow-orange streetlights. It's one of those things that never gets noticed. But the difference can be really appreciated if you go to a wealthy neighborhood where white light bulbs are still used. However, unless you're older and white, it's going to be a short time before the 'security guards' drive up with tasers and ask you what you're doing. If you're truthful and tell them that 'you're digging the cool white groove of the light, baby', then they will do what all mercenaries do when encountering a civilian harmlessly enjoying life, they will kidnap and assault you for their amusement.

    Anyway, a return to soft white lighting in the night will be most welcome.

Re:A return to white street light (0)

Anonymous Coward | about 9 years ago | (#13853014)

Where can I get some of whatever it is you are on?

Re:Something new for moths? (0)

Anonymous Coward | about 9 years ago | (#13852969)

It would be so cool to paint your walls with quantum dots so they emit light.

LED lights (4, Interesting)

totallygeek (263191) | about 9 years ago | (#13852828)

I have been impressed with the LED lights over florescent or incandescent. The subdued lighting is fine with me and the energy consumption / bulb longevity is the best part. When my wife and I move (build a house), we will go 100% LED.

It's all LIES (0)

Anonymous Coward | about 9 years ago | (#13852874)

So light makes them glow? Why is there no feedback loop here?

Re:LED lights (1)

carnivore302 (708545) | about 9 years ago | (#13852927)

Then you (and your wife) might want to have a look at Modern Optical Engineering [] , or if you are into math and can also appreciate the theoretical background of LEDs, hunt for Light Emitting Diodes [] , by Fred Schubert, who is somewhat of the pope in this field.

Re:LED lights (0)

Anonymous Coward | about 9 years ago | (#13852991)

I have been impressed with the LED lights over florescent or incandescent.

I prefer indecent lights.

"LEDs don't emit heat" (3, Interesting)

Tau Zero (75868) | about 9 years ago | (#13853038)

I wonder how many people are going to read this in the article and assume that LEDs are not just more efficient than other types of lamp, but 100% efficient?

(I hate scientifically-illiterate journalists.)

High Efficiency Homes and Power Consumption (1, Informative)

Anonymous Coward | about 9 years ago | (#13853047)

Hey, just thought I'd add that this site: FutureCrisis [] Has some really great tips on saving energy, peak oil and DIY electricity generation such as solar and wind power.

This brings up an important question (5, Funny)

Anonymous Coward | about 9 years ago | (#13852833)

How many cats does it take to change a quantum dot?

Re:This brings up an important question (4, Funny)

Geoffreyerffoeg (729040) | about 9 years ago | (#13852900)

Two, and you don't know which one will actually change the dot until the light turns back on.

Re:This brings up an important question (1)

Pfhorrest (545131) | about 9 years ago | (#13852909)

Depends, are they alive or dead? Or haven't you observed them yet?

Re:This brings up an important question (0, Redundant)

IcedZ (922502) | about 9 years ago | (#13852936)

It depends... are we talking about Schrodinger cats???

Re:This brings up an important question (1)

vertinox (846076) | about 9 years ago | (#13852951)

The other problem is that if you can tell wether the light bulb is on or off, you can't find out where it is.

Also, if you can locate where the light bulb is in your house, you won't be able to tell if it is on or off.

Re:This brings up an important question (1)

RazorRaiser (895600) | about 9 years ago | (#13852968)

don't you mean "How many dead cats would it take to make [] one?"

Re:This brings up an important question (1)

ThreeE (786934) | about 9 years ago | (#13852995)


leds (2, Interesting)

jsmucker (812692) | about 9 years ago | (#13852836)

I will go to leds when they meet my budget....just a matter of time.

Re:leds (1)

RedLaggedTeut (216304) | about 9 years ago | (#13853046)

I will go to leds when they meet my budget....just a matter of time.

Or the time of matter, since you can't measure both due to Heisenberg.

what the (0)

Anonymous Coward | about 9 years ago | (#13852840)

so..umm... to get light from this , I shine it with laser ?

...yea..i can always run off another line from my 220 /110 v to a laser source and direct that at this....

yup, goodby common light bulb.

It's about damn time! (4, Insightful)

Mysticalfruit (533341) | about 9 years ago | (#13852842)

Considering that the average lightbulb creates more heat than light, this is great!

Re:It's about damn time! (3, Funny)

winkydink (650484) | about 9 years ago | (#13852860)

Considering that the average lightbulb creates more heat than light...

Kind of like most slashdotters!

Re:It's about damn time! (5, Informative)

joostje (126457) | about 9 years ago | (#13852911)

Considering that the average lightbulb creates more heat than light, this is great!
As lightbulbs create about 95% to 98% heat (the rest is light), and modern LEDs about 85% to 96% heat, the LEDs still create more heat than light.

reference []

Re:It's about damn time! (2, Insightful)

Jedi Holocron (225191) | about 9 years ago | (#13852940)

Yeah, technically the LED itself doesn't throw out heat with the light it produces...however the "driver" (similar to a ballast on a flourescent fixture) or the electronics behind running/controlling the LED does produce a lot of heat. Reducing this ancillary heat production is another limiting factor to the adaptation of A Lamp replacement LED "bulbs".

Re:It's about damn time! (2, Interesting)

DrLex (811382) | about 9 years ago | (#13853013)

Actually LEDs do produce heat, albeit the ratio of heat/light is much lower than with incandescent bulbs. The common LED is designed for a maximum current of 20 ~ 30mA, and at these currents the heat production is negligible. You can drive them at a higher current, but then the heat production becomes significant and can cause the LED to burn out (and at real high currents, the junction simply breaks down immediately). The more performant Luxeon LEDs are attached to a tiny heatsink and the high power ones (3W and 5W) require an additional heatsink to use them beyond 1W.

Not sure this discovery is necessary (4, Interesting)

gvc (167165) | about 9 years ago | (#13852844)

White LEDs are already 3 times as efficient as mercury fluorescent, and fluorescent tubes are 3 times as efficient as incandescent. They (fluorscent and LEDs) can get pretty good colour accuracy, too, if they want to. The only thing holding them back is price. I'm not sure what this new invention might bring to the table in that regard.

Re:Not sure this discovery is necessary (1)

jumpingfred (244629) | about 9 years ago | (#13852862)

Can you point me to documentation of LEDs being 3 times as efficient as fluorescent? What I have mostly seen is that they are about the same efficiency. With the LEDs being about 3 to 4 times the cost.

Re:Not sure this discovery is necessary (2, Informative)

Jedi Holocron (225191) | about 9 years ago | (#13852910)

No, actaully, the thing holding back LEDs from practical home applications is the color of the light they produce. More specifically the color temperature [] .

Typical incandescent lighting comes in somewhere around 2800-3200K. White LEDs live somewhere around the 5000-7000K range. When an efficent LED source can be made at a color temperature similar to that of incandescent lighting...then you'll see it take off in as a replacement for a standard A Lamp.

This same color issue relates to the slow adaptation of Compact Flourescent lamps in homes. Only recently have they produced flourscent fixtures that have a similar color temperature to incandescent lighting.

Cost is certainly a factor...however if it LOOKS bad--meaning if it makes stuff look like crap to the average eye because it is the wrong or unexpected color temp--then people aren't going to use it no matter how cheap it is.

Re:Not sure this discovery is necessary (3, Informative)

gvc (167165) | about 9 years ago | (#13852949)

It is the incandescent colour that is the wrong temperature, not the LEDs. Mid-day sun is nominally 5600K, and morning/evening higher. So why do you want to emulate candle-light?

Completeness of spectrum is another issue. Cheap fluorescent tubes have huge mercury spikes and little red - maybe 55% on the accuracy scale. Good tubes achieve 95% - a marked difference. This is independent of the colour temperature.

White LEDs (at leat the ones you commonly buy today) are also fluorescent, but with pretty decent spectral accuracy. It would at least in theory be possible to build an RGB array of monochrome LEDS that would produce apparent white light.

Re:Not sure this discovery is necessary (1)

Jedi Holocron (225191) | about 9 years ago | (#13852980)

So why do you want to emulate candle-light?
I never said it was a good idea, just that IMO this is what is holding up the adoption of white LEDs. This is what people expect.

Completeness of spectrum is another issue.
Yes, Color Rendering Index rating is also an important factor that I did not mention. However, isn't the CRI index also tuned to incandescent lighting, because this is what the eye expects?

Re:Not sure this discovery is necessary (1)

DrLex (811382) | about 9 years ago | (#13853051)

It is the incandescent colour that is the wrong temperature, not the LEDs. Mid-day sun is nominally 5600K, and morning/evening higher. So why do you want to emulate candle-light?
Maybe because it looks cozy? I know many people who hate the typical fluorescent tube light because it's too harsh. When watching TV (or doing whatever) late at night, people don't want to have some bluish light shining in the background. It's as if you forgot to sleep and the first daylight is already shining through the curtains ;)

Re:Not sure this discovery is necessary (1)

John Hasler (414242) | about 9 years ago | (#13852964)

> Only recently have they produced flourscent fixtures that have a
> similar color temperature to incandescent lighting.

I specified flourscent fixtures that have a similar color temperature to incandescent lighting more than thirty years ago.

Re:Not sure this discovery is necessary (1)

pintpusher (854001) | about 9 years ago | (#13852960)

Current white LED fixtures put out color tempuratures around 5000K or more, which while close to "daylight" can be a fairly harsh blue-white light especially when compared to the common incandescent bulb putting out more like 3000K give or take. In the house, this can be pretty harsh light (think of that flourescent tube in the kitchen at 2:00 AM). Some fixtures attempt to make a warm glow by mixing in some red and yellow LED's in the matrix but frankly I think this looks stupid and doesn't really work. Also, white LED's are relatively expensive compared to colored LED's. I think the point here is that this quantum dot mixture could be used to generate a soft-white color, using current colored LED technology, less expensively than white LED's.

Re:Not sure this discovery is necessary (1)

zippthorne (748122) | about 9 years ago | (#13852967)

Not to mention that laser is just about the least efficient source of light.

White LEDs are not that efficient (1)

Bishop (4500) | about 9 years ago | (#13852992)

The very best white LEDs are only as efficient as CFLs under ideal conditions. LEDs are best used for low light levels. When used for higher light levels the LEDs overheat producing less light per watt. CFLs are still the best for household lighting.

Re:Not sure this discovery is necessary (1)

QuietLagoon (813062) | about 9 years ago | (#13852998)

White LEDs are already 3 times as efficient as mercury fluorescent, and fluorescent tubes are 3 times as efficient as incandescent.

From the article, LEDs produce twice as much light as a regular 60 watt bulb. I'm really not sure how to think about all of this. If LEDs produce twice as much light as a regular 60 watt bulb, how does that make LED lights better than compact fluorescent bulbs, which can produce four to five times as much light as an incandescent bulb of the same wattage?

What is missing in this discussion is the actual power used by all these devices.

Re:Not sure this discovery is necessary (1)

ottffssent (18387) | about 9 years ago | (#13853019)

Ultimately it's not pure price (initial cost) that will determine the success or failure of alternative lighting. Cost is obviously a factor, but there are enough situations where the up-front costs are secondary to the lifetime costs in determining whether a purchase will be made. And in many situations the replacement cost includes substantial extra costs (manpower, equipment, etc) over and above the light's purchase price, which make fluorescents and LED lighting relatively attractive.

As yet, LED lighting has certain problems other than its stupendous cost. In high-power situations, such as is required for room lighting, LEDs actually aren't more efficient than long-bulb fluorescents. They still last quite a bit longer and produce nicer light, but not enough to justify the cost. Assuming the latest Nichia and Luxeon LEDs represent an improvement on past technology that can be sustained, the future for LED lighting looks good. Other than price, the lights have little to hold them back. They're as good as or better than existing technology in nearly every respect, but the technology is still young, whereas incandescent and fluorescent lighting are both mature technologies with relatively less room for future improvement.

Unless this new technology exhibits a greater efficiency, has greater longevity, is substantially cheaper to produce, or exhibits some other dramatic improvement over current LED lighting, I don't see how it's really relevant. It may become so in the future but so far it looks like an interesting laboratory result, not an interesting lighting development.

Oh no! (4, Funny)

Trip Ericson (864747) | about 9 years ago | (#13852846)

But now we'll have to change our "how many x does it take the change a lightbulb" jokes!

"How many /. readers does it take the change a lightbulb? They don't have to because it's LED!"

Original Reference (0)

Anonymous Coward | about 9 years ago | (#13852850)

"This work is published online in the Oct. 18 edition of the Journal of the American Chemical Society."

No Effing Way!!! (3, Interesting)

Anonymous Coward | about 9 years ago | (#13852853)

Have you ever tried an LED light? They suck!!! They do not cast nearly enough light. The light color is a disturbing and unnatural color, usually with too much blue in it.

Florescent tubes are FAR superior to LED lights and yet so many people prefer good old incandescent lights to even florescent tubes. Hell, even something as simple as a flash light. Try an LED flash light and then try a xenon Mag Light and tell me which one rocks your socks.

LED lighting is one of those technology "revolutions" that are for the sake of technology. They are NOT better.

Re:No Effing Way!!! (0)

Anonymous Coward | about 9 years ago | (#13852869)

I have a headlamp that has 4 white LED's in them, they shine pretty bright for over 80 hours on 4 AAA's. Enough to see a good 10 feet in front of me. I havn't seen any florescent or incandescent lights work that well for that period of time.

Re:No Effing Way!!! (1)

jsmucker (812692) | about 9 years ago | (#13852873)

Buttttttt they are improving at a pretty fast rate, so in another 3-5 yrs things will be differnt. ( think differnt )

Re:No Effing Way!!! (1)

billyj (908794) | about 9 years ago | (#13852901)

Consistant misspeling is a virtue.

The greatest discoveries... (4, Insightful)

PGC (880972) | about 9 years ago | (#13852857)

are not followed by 'Eureka' , but by "Hey, that's funny" .

Re:The greatest discoveries... (1)

ehiris (214677) | about 9 years ago | (#13853000)

Who should I credit this quote to?

Re:The greatest discoveries... (5, Informative) (765901) | about 9 years ago | (#13853006)

Let's quote the source on that now shall we?
Isaac Asimov
"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...'" []

Re:The greatest discoveries... (1) (745183) | about 9 years ago | (#13853048)

The greatest discoveries... are not followed by 'Eureka', but by "Hey, that's funny".

...and used to be shown as a light-bulb going off. But now I guess that's out...

Schroedinger's Bulb (4, Funny)

dada21 (163177) | about 9 years ago | (#13852863)

If I close my bedroom door, my quantum bulb will neither be working nor burnt out.

Re:Schroedinger's Bulb (1)

ehiris (214677) | about 9 years ago | (#13853017)

Depending on who is observing the light might be off or the light might be on.
It's actually really good when you have a hot girl over and you want the light on while she wants the light off.

Re:Schroedinger's Bulb (2, Funny)

DJCater (877532) | about 9 years ago | (#13853050)

Stick with the cat analogy. Slashdotters won't know what 'having a hot girl over' means.

Re:Schroedinger's Bulb (1)

G-funk (22712) | about 9 years ago | (#13853055)

And then you tell her your best schroedinger's LED joke, and her quantum state becomes both sleepy and scared?

about time. (1)

CDPatten (907182) | about 9 years ago | (#13852866)

I can't wait until the day the masses move away from the traditional light buld. I have moved the majority of my home/office lights to leds with a combination of light tubes. I still use the traditional, but not as much, and usually for its warm glow, then its raw lighting effect.

Re:about time. (1)

Fishead (658061) | about 9 years ago | (#13853001)

My 300Watt Halogen Torchier just burned out the other day. I have it at the back of my desk, projecting onto the ceiling. With a dimmer installed, it makes the PERFECT light for using the computer.

When it burnt out, I had to resort to white Flourescent, or a 100Watt Incandescent bulb.

I gotta tell you, it SUCKED.

There is something to be said for having a soft, warm light that doesn't flicker like Flourescent. I couldn't wait to get back my "energy offender" bulb!!!

Screw efficiency, Halogen torchiers still produce the most comfortable light that I have ever seen.

If they could mimick the colour of Halogen using LED's, THEN maybe the masses and I will move away from the "traditional light bulb".

Oh, and LED Christmas lights SUCK. I hope my whole block switches to them so that my house will have the best looking lights without me doing any work.

From the FAQ on LEDs (5, Informative)

jkind (922585) | about 9 years ago | (#13852871)

Answer: there are several obvious advantages LEDs have over traditional incandescent light bulbs, they are as follows:
Low power consumption - energy saving,
Long lasting,
Cold lighting,
Small size and weight,
Fast switch times,
Simple to use.
This is from the FAQ, but it doesn't list any disadvantages..
anyone care to share?

Just a few disadvantages of LEDs (1, Interesting)

Anonymous Coward | about 9 years ago | (#13852944)

Disadvantages include:

Low candle power. LED lights are lacking in their production of, well, light.
Unnatural color. LED lights have unnatural and sometimes disturbing colors. Incandescent lights have a warm glow that is closer to natural light and "full spectrum" incandescents produce something very near sun light.
Expense! Producing an LED "bulb" with the same candle power as an incandescent bulb is FAR more expensive than the incandescent.
Possible health issues due to the poor light quality. A plant will grow under incandescent light, it will not grow under an LED.

Re:From the FAQ on LEDs (1)

loyukfai (837795) | about 9 years ago | (#13852966)

I think it's the initial procurement cost, high brightness LED are much more expensive than traditional bulbs.

Re:From the FAQ on LEDs (5, Informative)

Rob the Bold (788862) | about 9 years ago | (#13852972)

Some Disadvantages:

Like Fluorescent, requires supporting circuitry -- doesn't plug directly into AC wiring.
Cost (initial investment)
Harder to dim -- can't use simple rheostat
Flicker (if using less than 100% on time)

I don't have anything against LED lighting, and none of these disadvantages are insurmountable. Indeed, these could be viewed as business opportunities instead. Most of the disadvantages are shared with fluorescents, and adequate solutions already exist there. I know a guy who lights his whole off-grid house with LEDs (using low voltage DC wiring). I particularly like the possibility of creating variable color lighting with LEDs, emulating daylight, sunlight, tungsten or whatever.

Re:From the FAQ on LEDs (1)

MadScientistVX (924890) | about 9 years ago | (#13852975)

They are not quite as cold as people think. My dad has a 3 professional 1-3 Watt LED flash lights and although the light to heat ratio is great compared to traditional flash lights (not to mension, the quality of light is much better) It still emits a significant ammout of heat, which will become more evident as LEDs are used on a larger scale.

LED disadvantages (5, Interesting)

Temeraire (913731) | about 9 years ago | (#13853026)

Anyone who tries (like me) to build small lighting devices with LEDs rapidly discovers lots of practical difficulties. To equal the light output of one cheapo fluorescent tube you need hundreds of the little blighters. It is not easy to make their output look even, rather than dotty. And with that large number, reliability is a real problem. Even a 1% failure rate (amplified to 3% or 5% by the LEDs often being in series) rapidly translates into major unevenness. Even production lines struggle to make large arrays of LEDs stay 100% alight, but little people often get sold the bin ends, which fail rapidly in service.
      Also LEDs are NOT yet more efficient than fluorescents. Their data sheets never give the one number that really matters: what percentage of input energy actually emerges as light? The answer is usually frighteningly low. Therefore LED devices tend to cook themselves to death if run really bright.
      To run LEDs stably requires either a wasteful series resistor or an expensive semiconductor constant-current device. And cheap low-voltage power supplies are actually badly life-limited by their electrolytic capacitors. In my experience many LEDs die prematurely because of a failing power supply and hot sunshine.
      Don't get me wrong. LEDs are the future, but you must be wary of calling them energy-saving, long-lasting, or easy to use!

We'll need a replacement for the Goodyear Blimp! (5, Funny)

Anonymous Coward | about 9 years ago | (#13852882)

A LED Zeppelin, of course.

Re:We'll need a replacement for the Goodyear Blimp (4, Funny)

Pfhorrest (545131) | about 9 years ago | (#13852942)

Oh come now, that was highly uncalled for. Puns are for children, not groan adults.

(Note to mods: that's not a spelling error).

Good ole MSNBC... (1)

k31bang (672440) | about 9 years ago | (#13852883)

From TFA:
LEDs don't emit heat, so they're also more energy efficient

*cough* *cough*

Re:Good ole MSNBC... (1)

ElitistWhiner (79961) | about 9 years ago | (#13852941)

At least there is one /. poster who knows the efficiency of LED lighting is only popular myth. They consume the same power but last forever.

Re:Good ole MSNBC... (1)

loyukfai (837795) | about 9 years ago | (#13852948)

I'm not sure if LED "emits" heat but AFAIK, it does "produce" heat, and that's why LED torches need heatsinks because the performance of LED is negatively related to the its temperature.

Or it's something else?

Spelunkers Joy (2, Interesting)

joey_knisch (804995) | about 9 years ago | (#13852884)

About 7 Years ago I brought a LED Headlamp to a spelunker convention. They were leery at first but when I didn't change my batteries once during the entire weekend they were sold. The next year there were about 10/50 of us on LED. Now everyone has an LED lamp.

FTFA (2, Funny)

Associate (317603) | about 9 years ago | (#13852888)

When a brilliant idea pops into your mind in the future, what will appear over your head?

Answer: $$$

Ideas of the Future? (5, Funny)

Garridan (597129) | about 9 years ago | (#13852889)

"One big question remains: When a brilliant idea pops into your mind in the future, what will appear over your head?"

Smoke. That's one thing that I don't see changing any time soon. Not for me, anyway.

Re:Ideas of the Future? (4, Funny)

richdun (672214) | about 9 years ago | (#13852929)

Oh, I'm sorry, the correct answer was "an IP lawyer", "an IP lawyer." Well, thanks for playing! We have some wonderful parting gifts for you.

Biggest question (-1, Troll)

Tidal Flame (658452) | about 9 years ago | (#13852912)

Biggest question on everyone's mind: who honestly thought that that excerpt gives a good idea of what the article is about?

Thinkgeek (3, Informative)

Eightyford (893696) | about 9 years ago | (#13852913)

I'm totally surprised that they OSTG didn't pimp their LED bulb from thinkgeek. 35 bucks is a little steep though. []

Of course, you could always make your own. htm []

Think of the cartoons (0, Offtopic)

obli (650741) | about 9 years ago | (#13852919)

This'll totally screw it up for the cartoons who use the light bulb as a symbol for an idea, I hope you feel guilty...

LED efficiency versus Compact Fluorescents (4, Informative)

lancejjj (924211) | about 9 years ago | (#13852922)

This could be a big advance for LEDs. But as of now, commercially available LEDs do NOT produce as many lumens per watt as Compact Fluorescent Light bulbs (CFLs.) [] Of course, this new LED discovery may improve LED efficiency to the point where they exceed CFL efficiency. We'll have to wait and see.

CFLs are inexpensive and readily available today. CFLs have a long life, and they save a ton of energy when compared to traditional light bulbs. Even more importantly, they don't suck like the CFLs of a few years ago that had a noticeable/painful "warm up" time.

I save quite a bit off of my energy bill [] by using CFLs. They really cut down on electricity consumption, and I've never had one "burn out" on me. Ever. Yet.

Only two problems... (1)

JediTrainer (314273) | about 9 years ago | (#13853034)

I've replaced most of the bulbs in our house with CFLs and generally my wife and I love them. There are just two issues which are pretty darn annoying at times (basides their appearance, which isn't a problem given that I've put them in lamps that have shades or other covers).

The first is that the bulbs still have a warm-up time. Sure, they light right away, but it can take several minutes before they're at maximum brightness. This can be annoying, say, in a kitchen or other work area where I need all the light I can get so I can see what I'm doing.

The second annoyance is that I can't use them outdoors. Once the temperature reaches below 5 degrees C or so, they won't light up at all. So I'm still stuck using incandescents for my patio lights. They're iffy in the garage too (not as bright).

But I will agree that they save lots of money, particularly in the summer when you're running the air conditioner. Who needs more heat in the house when you're spending so much energy removing it?

Old news (1)

karvind (833059) | about 9 years ago | (#13852923)

Can anyone explain me why is this a new news ? Earlier demonstration [] by Sandia labs [] .


Costly Quantum Dots (4, Interesting)

ObligatoryUserName (126027) | about 9 years ago | (#13852935)

If the manufacturing breakthough talked about in this article [] pans out, the cost of Quantum Dot manufacture will drop from $2,000 to $400 per gram. That's huge improvement, but I still wouldn't expect to see Quantum Dot lightbulbs on ThinkGeek anytime soon...

"Accidental invention could light up the future" (1)

oskard (715652) | about 9 years ago | (#13852959)

Aren't they implying that most inventions are accidental then? Did he accidently hit the 'shine laser' button? Hm..

Current LEDs are not there yet (4, Informative)

The Optimizer (14168) | about 9 years ago | (#13852973)

I just finished converting the lighting in my house to save energy, and learned a few things in the process. Most of the incandescent bulbs were replaced with compact fluorescents, but I did install 4 LED light bulbs in one application.

The current generation of compact fluorescent bulbs has come a long way from the ones I remember 10-20 years ago. They don't have the flicker or startup problem anymore, and they are available in a variety of color temperatures from 2700 degrees (yellowish, comparable to incandescent) to 6100 degrees (white, sterile). For the same light output (lumens), energy consumption is normally 22% to 27% of the incandescent bulbs they replace. They very slightly in things like color and wattage depending on the manufacturer.

Nobody who has visited my home has yet noticed the difference.

Since you can find common CF bulbs sizes for under $2 per unit (try Sams Club, etc), and they should last 4 to 8 times as long as an incandescent, the economic case is pretty sound even before factoring in the energy savings.

I replaced 4x 7.5 watt bulbs with LED bulbs and noticed a few things. The LED bulb itself is about twice as large, and as others have mentioned, the light emitted is an eerie blue-white light. You defiantly notice it. These bulbs consume 0.8 watts and produce an output pretty close to the 7.5 watt bulbs they replaced, though I could not find the output in lumens for either bulb anywhere. They were about $7 a bulb, and are rated to last 100K hours, or about 50 times as long the bulbs they replaced. Since the bulb is actually made of up 18 individual LEDs inside, I believe the rating is for the mean time until 50% of the LEDs are no longer functioning.

After converting 152 of 160 bulbs in my home, my electric bill happy.

Re:Current LEDs are not there yet (1)

barjam (37372) | about 9 years ago | (#13852993)

I put a couple compact fluorescents in the garage hoping I wouldn't have to replace them as often (hard to reach) but for some reason they lasted only about half as long as a regular bulb.


Re:Current LEDs are not there yet (1)

DJCater (877532) | about 9 years ago | (#13853037)

>eerie blue-white light

Is that not just because we're used to yellow-white light?

led's, worse than flourescents. (3, Interesting)

plasmacutter (901737) | about 9 years ago | (#13852977)

I have an led flashlight.

led's emit a very cold light. Fourescent light is described as cold and "vitamin burning", but led light is even worse in this respect.

It works for headlights, emergency beacons, and select areas, but generalized room lighting is not one of those areas.

As a lighting design student... (5, Insightful)

maino82 (851720) | about 9 years ago | (#13852984)

I can definitely see the benefits of LEDs when compared to other forms of electric light. They do produce more lumens per watt than most other sources, but they do produce a good deal of heat when combined together into a large array, despite what people may tell you. They also have the added benefit of efficiently producing (since they only produce light in a certain wavelength) just about any color you would want through color mixing of different color LEDs (check out the tunnel in the Detroit airport if you'd like to see a well done example). Personally, though, I would love to see more daylight in spaces rather than a push for the latest and greatest in electric light. If done properly, daylighting can greatly increase light levels in the workplace and lower energy consumed by electric light. Generally, this will lead to an increase in cooling load, but this is almost always smaller than the amount of energy saved by eliminating electric lighting (again, if done properly). So while I'm all for more efficient electric lighting, it would be nice to see no electric lighting used during daylight hours when the sun is readily available.

Source of Light... (1)

loyukfai (837795) | about 9 years ago | (#13852987)

The main light source of the future will almost surely not be a bulb. It might be a table, a wall, or even a fork.

I suppose it means the new dots can be applied to many things but they still need another light or electricity source? Anyway, I'm not sure about others but I'm not yet ready to have everything in my home shines. : )

they already do this with blue LED's! (1)

Doppler00 (534739) | about 9 years ago | (#13852989)

That's how white LED's work if I'm not mistaken. Although instead of quantum dots, they use phosphor or some other material. Are quantum dots more efficient? Try this: Take a blue LED and shine it into a white LED that is turned off. You should see a slight white glow from the white LED, even though the originating light source is blue! Kind of a neat and simple experiment.

Perty white light... (2, Funny)

Gothmolly (148874) | about 9 years ago | (#13852990)

The quantum dots were supposed to emit blue light, but instead they were giving off a beautiful white glow.

I bet Marie and Pierre Curie thought something similar at one point. "Hey look, this lump of weird metal that we produced is glowing so pretty... hey, if I put it in my mouth, my eyes glow too! Fun!"

From TFA (1)

Beautyon (214567) | about 9 years ago | (#13853004)

"One big question remains: When a brilliant idea pops into your mind in the future, what will appear over your head?"

A Dollar sign? ... or more likely since we are talking about the future, a €uro sign.

What happpens to all of our sockets? (0)

Anonymous Coward | about 9 years ago | (#13853007)

We have, what, 20 billion light bulb sockets in the world? Will they gather dust? Do they have a dim future?

What do you think! (1, Funny)

Anonymous Coward | about 9 years ago | (#13853012)

FTFA "One big question remains: When a brilliant idea pops into your mind in the future, what will appear over your head?"

A lawyer?

Still a way to go yet. (2, Interesting)

crawdad62 (308893) | about 9 years ago | (#13853022)

I'm a professional firefighter and a lot of the guys have started using LED flashlights. I had just purchased my own (out of my pocket and not the city's) rechargeable StreamLight that uses a halogen bulb. When I started seeing the LED's showing up I thought I had made a mistake. They "seem" bright but after seeing them more and more I'm convinced it's just because the light is so white (slightly blueish) and clean.

However even though it looks brighter in fact it's less so and seems to accentuate shadows MUCH more.

I really haven't discussed power consumption with anyone yet but for now........ at least in this application....... I'll stick with the older technology.

super bright white light.... (1)

lightningrod220 (705243) | about 9 years ago | (#13853027)

The front of my Mac has a white light, which I assume is an LED, that creates a "pulse" effect when the computer is on standby. That thing is so bright, I had to cover it up to keep it from being so bright that it would keep me awake... and it was less than a millimeter in diameter! Is that an LED? If it is, I would agree on the idea of using it as a light source.

Spectrum? (1)

Crouty (912387) | about 9 years ago | (#13853036)

What the article does not tell is the kind of spectrum these quantum dots produce. Chances are most people will not feel comfortable living or working with this kind of light. Any info on this yet?

Would I need a laser? (1)

ehiris (214677) | about 9 years ago | (#13853040)

I don't understand. Would I have to shine a laser on my new quantum dot light bulbs or could they get activated differently? Using a laser doesn't seem too practical.
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