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Laser Blast Makes Regular Light Bulbs Super-Efficient

ScuttleMonkey posted more than 4 years ago | from the bright-ideas dept.

Power 559

guruevi writes with news that a process using an ultra-powerful laser can crank up the efficiency of everyday incandescent light bulbs. Using the same laser process covered several years ago, the tungsten filament has an array of nano- and micro-scale structures formed on the surface making the resulting light as bright as a 100-watt bulb while consuming less electricity than a 60-watt bulb and remaining much cheaper to produce. "The key to creating the super-filament is an ultra-brief, ultra-intense beam of light called a femtosecond laser pulse. The laser burst lasts only a few quadrillionths of a second. To get a grasp of that kind of speed, consider that a femtosecond is to a second what a second is to about 32 million years. During its brief burst, Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point. That intense blast forces the surface of the metal to form nanostructures and microstructures that dramatically alter how efficiently light can radiate from the filament."

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Now I Understand Lasers (5, Funny)

eldavojohn (898314) | more than 4 years ago | (#28173229)

Laser Blast Makes Regular Light Bulbs Super-Efficient

So that whole time in Star Wars, they were just trying to make each other Super-Efficient? That's a whole lot nicer than what I was led to believe was initially going on.

LASIK makes a lot more sense now too.

I'm learning!

Re:Now I Understand Lasers (4, Funny)

gnick (1211984) | more than 4 years ago | (#28173323)

I think you just redefined "learning". But, it is in line with a lot of the "facts" I've picked up on /.

Re:Now I Understand Lasers (5, Funny)

cheftw (996831) | more than 4 years ago | (#28173913)

Well I just learned how femtoseconds work. Thanks to TFS.

Though it might have been more helpfully put if they said that a car travelling at 40 furlongs per fortnight goes 6.652x10^-8 Angstroms in a femtosecond.

Re:Now I Understand Lasers (5, Funny)

sesshomaru (173381) | more than 4 years ago | (#28173347)

James Bond: Do you expect me to talk?

Auric Goldfinger: No, Mr. Bond, I expect you to be more efficient!

Re:Now I Understand Lasers (4, Funny)

bugnuts (94678) | more than 4 years ago | (#28173527)

Couple this thing with a few femtosharks, and my high-efficiency evil lair will be complete.

This just in... (0)

Anonymous Coward | more than 4 years ago | (#28173249)

Shark unemployment figures, widely considered a key indicator of the viability of the global economy, recently dropped to a mere 1% following this announcement.

Re:This just in... (-1, Troll)

Anonymous Coward | more than 4 years ago | (#28173463)

Me and Steve Jobs shove iPhones up each other's asses for fun.

Re:This just in... (5, Funny)

Anonymous Coward | more than 4 years ago | (#28173569)

There's an app for that.

Re:This just in... (0)

Jurily (900488) | more than 4 years ago | (#28173683)

Shark unemployment figures, widely considered a key indicator of the viability of the global economy, recently dropped to a mere 1% following this announcement.

Efficiency also means less full-time people are needed for the same amount of work.

And they will hit the shelves in... (5, Funny)

pandymen (884006) | more than 4 years ago | (#28173285)

So, considering they are as cheap to produce as normal lightbulbs, we can expect to see these on the shelves in...2050?

High-efficeiency incandescent bulbs (5, Informative)

Verteiron (224042) | more than 4 years ago | (#28173291)

But it doesn't matter (at least to those of us in the USA), because in 2014 incandescent bulbs will be banned.

Re:High-efficeiency incandescent bulbs (3, Informative)

freedumb2000 (966222) | more than 4 years ago | (#28173459)

Same in europe.

Re:High-efficeiency incandescent bulbs (0, Insightful)

Anonymous Coward | more than 4 years ago | (#28173481)

Don't worry, they still suck compared to true high effecency bulbs so it's no great loss. In this case HE incandecent is bassicly the same as the smartest retard in the room.

Re:High-efficeiency incandescent bulbs (0, Redundant)

MightyMartian (840721) | more than 4 years ago | (#28173571)

Whatever they're inefficiencies, they certainly are not the polluters that CFLs are. I'd sooner have shitty energy inefficiency and not be dumping even more mercury into the environment.

Re:High-efficeiency incandescent bulbs (5, Informative)

Grishnakh (216268) | more than 4 years ago | (#28173803)

Since most power plants in the US (and many other countries too) burn coal, which contains mercury, these slightly-more-efficient incandescent lights will most likely end up dumping more mercury straight into the atmosphere (and then into the waterways with rain) over their lifetime than CFLs, which contain the mercury within the bulbs.

So in your quest to avoid mercury pollution by using incandescent bulbs, you're actually causing MORE mercury pollution in the long term.

Re:High-efficeiency incandescent bulbs (0)

Anonymous Coward | more than 4 years ago | (#28173863)

How much mercury (and other pollutants) comes from the coal ash to power the inefficient incandescents?

Re:High-efficeiency incandescent bulbs (3, Insightful)

Chris Mattern (191822) | more than 4 years ago | (#28173665)

Watch for sales of incandescent bulbs to triple in 2013.

Re:High-efficeiency incandescent bulbs (1)

MyLongNickName (822545) | more than 4 years ago | (#28173821)

That sucks for me. I bought some GE compact florescent bulbs two years ago. They lasted about half as long as incandescent bulbs. Yeah, I know what they are supposed to last forever. I am not sure what the reason is, but the things will not last. Tried a couple more times, but same result. After several weeks the things just stopped working. I may experiment again, but at the steep cost I don't like wasting money.

Re:High-efficeiency incandescent bulbs (1)

Sponge Bath (413667) | more than 4 years ago | (#28173825)

That gives them 5 years to make a shipping product. If the efficiencies and production costs are as claimed, the law will be changed to a more sane efficiency based metric instead of dictating particular technologies.

If 5 years pass and nothing comes of this, as is often the case with these kinds of announcements, then no loss.

Too late (3, Insightful)

K. S. Kyosuke (729550) | more than 4 years ago | (#28173297)

Of only white LEDs were this efficient as well...oh wait...never mind.

Re:Too late (1)

TooMuchToDo (882796) | more than 4 years ago | (#28173415)

Bingo. And they're much easier to make than having to shoot a powerful laser at a tungsten filament.

Re:Too late (4, Funny)

b4dc0d3r (1268512) | more than 4 years ago | (#28173711)

But... with LEDs you don't get to shoot a powerful laser at a tungsten filament!

Re:Too late (1)

gnick (1211984) | more than 4 years ago | (#28173475)

I thought the same thing - Even after alteration these things aren't as efficient (in a Lumens/Watt context) as CFLs or LEDs. But TFA does point out that the advantage is the more "natural" light. I use both CFLs and incandescents at home - The light from the "normal" bulbs is just nicer IMO. The entry price for LEDs is too high for me to look too seriously and (despite possibly being environmentally friendlier), they're not as energy efficient as the CFLs.

Re:Too late (1)

thedonger (1317951) | more than 4 years ago | (#28173671)

The entry price for LEDs is too high for me to look too seriously and (despite possibly being environmentally friendlier), they're not as energy efficient as the CFLs.

I could swear I read that LEDs were at least three times as efficient as CFLs...Either way, they dim way better, and last way, way longer. I use LED and CFL at home, and the CFL dim noticeably in a fairly short amount of time - a matter of months. And I can throw an LED away in the trash (not that I ever will have to given normal use).

Re:Too late (1)

samkass (174571) | more than 4 years ago | (#28173759)

In theory, LEDs should be very efficient. However, it is actually really difficult to make a LED that "natively" emits green light. Blue LEDs and red LEDs are both much easier. So a "white" LED is really a blue LED driving the fluorescence of some coating which saps away a lot of the efficiency. What you get is a very expensive bulb with a spectrum no better than a CFL and efficiency in the same ballpark as well. The lifetime is dramatically better, though.

I believe there have been several Slashdot stories about ways of getting "native" efficiencies in a LED lightbulb, so I would expect the cost and performance of LED to have way more of a future than CFL, which are still Mercury-filled, hand-made monstrosities in comparison. But right now it's a hard sell.

Re:Too late (1)

Andy Dodd (701) | more than 4 years ago | (#28173827)

Nope. Actually, until recently, LEDs were about on par with halogen incandescent bulbs. (Not standard incandescents though).

LEDs have improved 2-3x in efficiency in the past 4-5 years allowing them to pass halogens in efficiency, but still probably not on par with CFLs.

LEDs dominated in the flashlight market because of two reasons:
1) Halogen bulb efficiency and durability increases with bulb size. Flashlight-sized bulbs were far less efficient and had typical lifetimes well below 100 hours, compared to full size halogen bulbs in the hundreds of watts range
2) LEDs dim much more gracefully in battery powered devices. An LED at 1% of its power still gives usable light, while an incandescent at 1% power may as well be turned off. Even at 50% power an incandescent shifts color significantly to the red, reducing visible light efficiency by massive amounts.

Re:Too late (1)

K. S. Kyosuke (729550) | more than 4 years ago | (#28173797)

It is "more natural", of course. It's a black body radiation, or at least something much closer to it. There will always be applications for this - in photography, for example. But as far as the price of LEDs is concerned, when I did my calculations, the the cost of using a LED seemed to be very compelling, even when the price of the hardware is considered. As far as I know, commercially available LEDs are already actually *more* energy-efficient than CFLs. And the lifetime is very nice as well, it should offset the initial investment.

Surprising, actually... (4, Insightful)

fuzzyfuzzyfungus (1223518) | more than 4 years ago | (#28173307)

The technique has been used to make extremely efficient light-absorbing surfaces; but hadn't been applied to light-emitting surfaces until now. Since those are two sides of the same coin, I'd have expected somebody to try it much sooner(though, I'll admit, I didn't think of it).

On the plus side, greater efficiency in incandescents is always good(though I'd be quite interested to know how cheap laser treating filaments can possibly be). I predict that this thread will probably be infested by the "CCFLs are Evil!" brigade soon enough...

Re:Surprising, actually... (1)

Locke2005 (849178) | more than 4 years ago | (#28173697)

Compact Florescents ARE evil! They make audible NOISE dammit! The LCD bulbs' only flaw is that they are extremely directional -- good for spot lights, not so good if you want diffuse lighting. Screw an LCD bulb into a old tabletop lamp socket, and you'll get a nice bright spot of light... on the ceiling.

Re:Surprising, actually... (0)

Anonymous Coward | more than 4 years ago | (#28173735)

How does it improve the efficiency though? Any light not leaving the filament isn't lost but heats the filament when it is absorbed back. In the end only the surface interacts with the environment. The problem is different for LEDs, because in LEDs it isn't the heat which creates the light, so absorbed light inside the LED is really lost.

super efficent? (0)

Anonymous Coward | more than 4 years ago | (#28173313)

How can they call ~60w for the same light as a regular 100w for super efficient?? Both florescent and LED lightning are a LOT more efficient than that and I think HID lights are as well!

Re:super efficent? (1)

fuzzyfuzzyfungus (1223518) | more than 4 years ago | (#28173431)

These bulbs are super efficient in the same way that racehorses are super fast. Compared to newer technologies, not so much; but pretty damn good compared to their fellows(particularly impressive in that lightbulbs have been a mature technology for some time).

Consistency (4, Insightful)

qoncept (599709) | more than 4 years ago | (#28173315)

... and remaining much cheaper to produce.

... Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point.

What?

Re:Consistency (1)

Bruiser80 (1179083) | more than 4 years ago | (#28173387)

The entire power used in the North American grid isn't too bad when you're only using it for a fermentosecond :-)

Re:Consistency (1)

funwithBSD (245349) | more than 4 years ago | (#28173423)

But only for a femtosecond.

Re:Consistency (1)

clone53421 (1310749) | more than 4 years ago | (#28173443)

I didn't get that either... especially when I read TFA and it said that it is able to be run from a standard wall outlet.

I'm guessing that the power used by the entire North American grid in a few quadrillionths of a second isn't really that much.

Re:Consistency (2, Informative)

artg (24127) | more than 4 years ago | (#28173655)

Approx. energy used by NA grid in one year, 4x10^12 kWh Approx. mean power to achieve this, 4.5x10^11 W Approx. energy used in one femtosecond pulse 4.5x10^-4 Ws = 1.26x10^-10 kWh So quite a high repetition rate is allowed before the energy usage is noticeable.

Re:Consistency (1)

RingDev (879105) | more than 4 years ago | (#28173587)

If my math is correct (and it is a BIG if) it's only the equivalent of like 370 watt/hr.

-Rick

Re:Consistency (1)

shermo (1284310) | more than 4 years ago | (#28173707)

It's watts*hours. Not watts per hour.

Re:Consistency (4, Informative)

sjames (1099) | more than 4 years ago | (#28173639)

... Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point.

What?

For one femtosecond (10^-15 seconds). Rough figure from the world factbook shows the U.S. + Canada averaging 497 GW. So, if the laser fired one thousand pulses per second, it would only draw 5 W from the wall (assuming 100% efficiency). It's another case of really big numbers combining with really small numbers to yield nothing spectacular.

Re:Consistency (1)

interkin3tic (1469267) | more than 4 years ago | (#28173861)

It's another case of really big numbers combining with really small numbers to yield nothing spectacular.

Disco stu: Did you know that disco record sales were up 400% for the year ending 1976? If these trends continues... AAY!

Re:Consistency (1)

tenco (773732) | more than 4 years ago | (#28173681)

During 1 femtosecond. Power = Energy/Time. I don't know how much power the entire grid of north america puts out, but to give an example: 1 joule of energy delivered in 1 femtosecond would be equal to about 1 peta watts of power. Actually a LASER-pulse wouldn't be of the form of a box function but more a gaussian or sth. similar. So the peak power would be higher than this averaged output.

BTW, femtosecond LASERs have been around for quite some time. Attosecond LASERs have already been made.

So what about the places that have banned these? (4, Insightful)

Anonymous Coward | more than 4 years ago | (#28173327)

Why not set an efficiency factor on a bulb(like cafe standards) instead of banning the different technologies?

Something I never understood.

Re:So what about the places that have banned these (2, Interesting)

Kokuyo (549451) | more than 4 years ago | (#28173513)

Oh, that's easy to answer. It's a tag. Makes it easy to spot where people have been bought to push certain agendas and fill pockets. Let me just ask you this: Do you think profit margins on old-school bulbs are a) smaller or b) larger than on more modern alternatives?

Whenever legislation is worded in such a way that it does not encourage competition to reach a certain goal, you can bet your cute fanny that the true goal of said legislation lies not in the stated goal but in the way as to get there.

That's basically why I'm for voting for politicians AFTER they've been in office. The outcome of said vote will decide how much pension the person gets for the work done. If abysmal enough, I'm all for incarceration.

Re:So what about the places that have banned these (2, Insightful)

Locke2005 (849178) | more than 4 years ago | (#28173731)

You mean like they mandated emission standards instead of requiring every car to be built with a catalytic converter? Who would be silly enough to pay for lobbying for a law that doesn't favor their own industry while penalizing their competitors?

Too late? (2, Insightful)

Bruiser80 (1179083) | more than 4 years ago | (#28173351)

Too bad we won't be able to buy Incandescents any more in a couple years....
http://www.formplusfunction.com/blog/2009/will-incandescent-bulbs-soon-be-outlawed/ [formplusfunction.com]
unless they can get the new bulbs to 70% less power used. :-(

The clock is ticking to 2014 (when 40watts are outlawed).

sorry for the link, didn't have time to find a reputable site...

Re:Too late? (1)

Grishnakh (216268) | more than 4 years ago | (#28173897)

So what do they propose to do about the bulbs inside kitchen ovens? You can't exactly put a CFL bulb in a 500-degree oven.

Too late (4, Insightful)

the_other_chewey (1119125) | more than 4 years ago | (#28173363)

Too late: Compact fluorescent lamps require about 20W for the same light output as a 100W incadescent.
And live longer too.

Yes, their light used to look shitty, but these times are over now as well - if you don't buy the cheapest
there are, the light out of fluorescent bulbs is perfectly fine. And LED "bulbs" may soon be there too.

Re:Too late (4, Informative)

digsbo (1292334) | more than 4 years ago | (#28173493)

Yeah, and they contain enough mercury to poison 4000 gallons of drinking water! Yay!

Re:Too late (1)

digsbo (1292334) | more than 4 years ago | (#28173541)

Re:Too late (3, Informative)

rev_sanchez (691443) | more than 4 years ago | (#28173877)

A lot of mercury is released into the atmosphere from burning coal for electricity. According to the Australian version of the EPA [environment.gov.au] , powering a traditional incandescent light bulb will release of about 13.4mg of mercury over its lifetime versus 2.7mg for a CF bulb. CF bulbs contain 5mg of mercury or less so if you didn't recycle any you'd still release less mercury than would have been released by an incandescent bulb.

Home Depot recycles them for free now and infrastructure to recycle them is spreading all of the time.

Re:Too late (1)

hamburger lady (218108) | more than 4 years ago | (#28173773)

thanks, you had to tell me after i threw my broken bulb down the well.

Re:Too late (1)

dunkelfalke (91624) | more than 4 years ago | (#28173791)

4000 gallons of dihydrogen monoxide are nothing to laugh at either and are also more than enough to kill.

Re:Too late (1)

tool462 (677306) | more than 4 years ago | (#28173793)

Well, stop flushing your bulbs down the toilet after they burn out then... ;)

Re:Too late (2, Informative)

Locke2005 (849178) | more than 4 years ago | (#28173809)

Compact florescents emit audible noise. Incandescents only emit noise if you but a cheap dimmer switch on them that chops up the sine wave. LEDs, as far I can tell, are silent. LEDs have good enough light now, they just need to be cheaper.

Re:Too late (1)

the_other_chewey (1119125) | more than 4 years ago | (#28173901)

Compact florescents emit audible noise.

Cheap (and older) ones do, yes. I seriously dooubt you can hear the >40kHz
switching fequency of current models. I sure can't, and I have excellent hearing.

Super Efficient? (0, Redundant)

Crazy Man on Fire (153457) | more than 4 years ago | (#28173369)

Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point.

So, by only using as much power as the entire grid of North America, we can make a "less than 60 watt" bulb as bright as a 100 watt bulb? Perhaps it operates more efficiently, but it doesn't sound like it is so efficient to produce. Unless I'm misunderstanding or misrepresenting the verbiage from the summary.

Re:Super Efficient? (2, Insightful)

Fulcrum of Evil (560260) | more than 4 years ago | (#28173441)

No, that's just a mainstream news unit of measure. We now have football fields, libraries of congress (LOCs), swimming pools (for area?), and the entire power output of the north american energy grid.

Re:Super Efficient? (4, Informative)

tjstork (137384) | more than 4 years ago | (#28173471)

Perhaps it operates more efficiently, but it doesn't sound like it is so efficient to produce. Unless I'm misunderstanding or misrepresenting the verbiage from the summary.

You forgot that femtosecond part. The usage of the whole USA grid is for an incredibly tiny fraction of a second, 10^15 of a second. The USA grid is 4x10^15 watts. So really, if you want to translate it into a more sane energy understanding, its about four watts per bulb to do this.

Re:Super Efficient? (4, Informative)

clone53421 (1310749) | more than 4 years ago | (#28173579)

You screwed up your units, there. (watts)x(seconds) = joules [google.com] .

You also forgot the negative on the exponent, but I'll forgive you for that...

Re:Super Efficient? (0)

Anonymous Coward | more than 4 years ago | (#28173907)

You also forgot the negative on the exponent

No he didn't

"10^15 of a second"

Re:Super Efficient? (0)

Anonymous Coward | more than 4 years ago | (#28173613)

Perhaps it operates more efficiently, but it doesn't sound like it is so efficient to produce. Unless I'm misunderstanding or misrepresenting the verbiage from the summary.

You forgot that femtosecond part. The usage of the whole USA grid is for an incredibly tiny fraction of a second, 10^15 of a second. The USA grid is 4x10^15 watts. So really, if you want to translate it into a more sane energy understanding, its about 4 Watt seconds/pulse to do this.

Fixed that for you

Re:Super Efficient? (0)

Anonymous Coward | more than 4 years ago | (#28173517)

Sure, it's lots of power, but only for thousandths of a millionth of a millionth of a second. So it really isn't so much energy afterall.

dom

Re:Super Efficient? (2, Insightful)

yoghurt (2090) | more than 4 years ago | (#28173621)

Let's do the math. From that fount of knowledge that is wikipedia, the US grid is about 4 thousand terawatts. That's 4*10^15 W.

So say we want over 4 times that, like 20*10^15 W to give 4 times the power of the US grid.

Power is energy divided by time. 1 femtosecond is 10^(-15) sec.
Let energy in joules be E, power in watts be P and time in seconds be T, then
      E = P*T
So the energy of power 20*10^15 W times times time 10^(-15) is just 20 Joules.

Say it takes 1 sec to pump the laser, that's an average power of 20W. Of course the laser pumping
isn't 100% efficient, and 1 sec might not be the exact right time, it's still feasible. It's only the equivalent
energy of having the light bulb lit for a few seconds.

Re:Super Efficient? (1)

pz (113803) | more than 4 years ago | (#28173695)

Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point.

So, by only using as much power as the entire grid of North America, we can make a "less than 60 watt" bulb as bright as a 100 watt bulb? Perhaps it operates more efficiently, but it doesn't sound like it is so efficient to produce. Unless I'm misunderstanding or misrepresenting the verbiage from the summary.

What the summary fails to convey accurately is that femtosecond lasers while often delivering a paltry average power of a few (hundred) milliwats, have the mentioned immense bursts of power for almost unimaginably short periods of time with unmentioned comparatively long periods of quiescence. Peak illumination levels that approach or exceed levels at the surface of the sun are not unheard of; the filaments in question are certainly undergoing microscopic explosive plasma ablation. But, remember, such laser pulses last a very, very, very brief period of time and there's no laser illumination to speak of between these pulses, so that the average power is reasonably low.

Think of it this way: take a 5 mW continuous laser, like your favorite laser pointer. Turn it on for 1 second. Now imagine taking the gazillion photons that were emitted during that entire second and emitting them all in 1 femtosecond (remember, milli-, micro-, nano-, pico-, femto-). You still have 5 mW-seconds worth of photons, but the peak photon flux will be a thousand times a thousand times a thousand times a thousand times a thousand times brighter (that's 10^15 X brighter). That's more-or-less what femtosecond lasers do.

Re:Super Efficient? (0)

Anonymous Coward | more than 4 years ago | (#28173721)

Idiot.

USA used 29000 TWh 2005. Equals 3.3 TW mean usage.

1 femtosecond times 3.3 TW /(3600/10^-15 femtoseconds per hour) equals 9 * 10^-10 Watt hours.

I will not go into a calculation in how many microseconds you have earned that energy if the bulb produces 66% more light.

Please respect energy balances and keep things in perspective.

Laser Blast? (1)

wiggles (30088) | more than 4 years ago | (#28173375)

Am I the only one who thought of this [gamespot.com] ?

Re:Laser Blast? (0)

Anonymous Coward | more than 4 years ago | (#28173549)

Nope. I thought of it too. Being one of the few people at the time to complete it and give Atari proof for my badge. The score digits all turn to spacecraft, and that's the end of the game. Whoo do!

Too Bad. Too Late. (0)

Anonymous Coward | more than 4 years ago | (#28173377)

Wow, so you can have the "right" light and efficiency as well! Too bad they outlawed incandescent bulbs.

Care for another cup of mercury under the crappy flickering light?

super! (2, Funny)

u4ya (1248548) | more than 4 years ago | (#28173393)

and it only takes 11 years of operating the more efficient bulb to compensate for the energy consumed during the laser burst

Try less than a second. (2, Informative)

Chris Burke (6130) | more than 4 years ago | (#28173807)

Energy and Power are not the same. Specifically, Power is Energy divided by Time. W = E/t

Based on just the US [wikipedia.org] , which for the sake of half-arsed napkin engineering on /. I will double to get total energy usage for North America in 2005, we're talking about 58000 TWh / 8760 h = 6.621 TW average power output.

Thus the laser pulse itself uses 6.621E12 W * 1E-12 J = 6.621 J.

The "efficient" lightbulb saves 40W. 6.621 J / 40 W = 0.165 s.

So it takes less than a second to recover the energy used by the laser. I'm sure the laser system itself uses more power than what is just in the beam, but the point is, ridiculous amounts of power in ridiculously short amounts of time results in quite rational and manageable power levels.

Re:Try less than a second. (2, Informative)

Chris Burke (6130) | more than 4 years ago | (#28173855)

6.621E12 W * 1E-12 s = 6.621 J.

oops.

Also, I said "power" instead of "energy" at the end of my post. Heh.

FFS use standard units. (4, Informative)

B5_geek (638928) | more than 4 years ago | (#28173397)

This is the might Slash. We can understand proper units.

Femto = 10^-15

Lifetime (3, Insightful)

snsh (968808) | more than 4 years ago | (#28173399)

But long does the lamp last? It's easy to make an incandescent lamp more efficient. You just crank up the filament temp, but then your lifetime goes to pot. Lamps last 1000 hours because that's how frequently consumers are willing to unscrew and rescrew their bulbs.

Re:Lifetime (1)

CaseyB (1105) | more than 4 years ago | (#28173537)

No doubt this research was funded by GE. They'd love to increase the efficiency of incandescent bulbs, while having them maintain their fragility and short lifespan. Thankfully it's coming too late to avoid the ban. Bring on the LEDs, and good riddance to the notion of light sources as consumable products.

Re:Lifetime (0)

Anonymous Coward | more than 4 years ago | (#28173663)

Funny, GE is behind LED lighting. Go check out your local walmart, they carry LED PAR40 bulbs made by GE. They currently cost about $30 for a 40watt equivalent, but they give off light that looks as good an incandescent.

I couldnt find pics of the PAR40 bulb, but here is the PAR20 bulb, also sold at walmart

http://www.atrlighting.com/images/banner_GE_PAR_LED_01.jpg

Incandescent will never be called efficient. (1)

Behrooz (302401) | more than 4 years ago | (#28173405)

So, a standard incandescent bulb puts out something like 10-15% of the energy input as visible light? ...and this process boosts that up to maybe 15-25% efficiency?

This is interesting from a materials science perspective and for lighting technology in the near-term, but hardly what I'd call super-efficient. Wake me up in a couple years when they have the bugs worked out of LED lighting...

Energy Savings? (-1, Redundant)

dhall (1252) | more than 4 years ago | (#28173433)

How many lightbulbs would they need to convert from 100W to 60W usage (over time) to equal the energy cost of 1 femto second laser blast that "unleashes as much power as the entire grid of North America"?

As much power as the US grid..? (0)

Anonymous Coward | more than 4 years ago | (#28173455)

If a femtosecond blast of the laser "unleashes as much power as the entire grid of North America," why don't we use the blessed thing to power that grid?
Or is it also taking in "as much power as the entire grid of North America" to create that blast? (I would never suggest breaking the law, even laws of physics!)
And what does "as much power as the entire grid of North America" mean, anyway? As much power as is in the grid right now? Over the span of a day..? a year...?

Cheaper to produce? (0)

Anonymous Coward | more than 4 years ago | (#28173467)

100 watt lightbulb = expensive = 60 watt lightbulb + laser = cheaper??

head asplode!

Burn energy to get efficient? (0)

JazzCrazed (862074) | more than 4 years ago | (#28173497)

Sounds like a pretty powerful laser to me. Does the energy used by this process significantly counteract any efficiency gained in the bulbs' use thereafter?

Re:Burn energy to get efficient? (1)

JSBiff (87824) | more than 4 years ago | (#28173737)

Well, they never actually say how *much* energy is used, specifically, to calculate the energy used, *but* I'm gonna go out on a limb and say that since the laser pulse only lasts a femtosecond (they do say that, specifically), it's not really using that much energy. Femto prefix indicates 1*10^-15, or 1 divided by a number which is 1 with 15 zeroes after it. That's an incredibly small amount of time. So, even if the power used is rated in Gigawatts, or even thousands of Gigawatts, remembering that Watts = Joules per second, the actual Joules of energy used is likely to be very small, because of the much-less-than-1-second time it runs.

It's like thinking in terms of, if I'm traveling at a speed of 1 million miles per hour, for one femtosecond, how far have I moved? Answer: 0.0000000176 inches.

Correction of first sentence. . . (1)

JSBiff (87824) | more than 4 years ago | (#28173811)

The first sentence should have read: "Well, they never actually say how *much* power is used,. . ." (emphasis only to show the change).

Too bad (1, Interesting)

Anonymous Coward | more than 4 years ago | (#28173505)

GE and Philips have already bought and payed for the public perception of which types of lightbulbs are green, and which ones make you a remorseless monster who's worse than hitler.

Hint: the 'green' one is the one with the enormous profit margin.

Just use all the Electricity up front. (0, Redundant)

Malluck (413074) | more than 4 years ago | (#28173523)

(29,000 terawatt hours = total power used in 2005 by US) / (1 femtosecond) = 1.04400 × 10^35 watts (US useage per femtosecond)

If this much juice is used to make the filiment, how is this more efficient?

Re:Just use all the Electricity up front. (1)

chonglibloodsport (1270740) | more than 4 years ago | (#28173679)

Because wattage is a unit of power, not energy.

This laser doesn't use very much energy, even though it produces a focuses a huge amount of power on a small area.

Re:Just use all the Electricity up front. (1)

Malluck (413074) | more than 4 years ago | (#28173789)

Scratch that. I screwed up the units.
It comes out 104400 Joules or 29 Watt Hours.

Re:Just use all the Electricity up front. (1)

Bryansix (761547) | more than 4 years ago | (#28173833)

Because you math is wrong? Don't worry, I failed college algebra the first time too.

Not really super-efficient (2, Insightful)

divide overflow (599608) | more than 4 years ago | (#28173533)

Even if the luminous efficacy improves a 60 watt incandescent to that of a 100 watt bulb that still puts it around 29-30 lumens per watt, about 30% of a good fluorescent or LED light source.

This is a nice improvement for an inherently inefficient and quite dated technology, but hardly but hardly "super-efficient" in the larger sense of overall luminous efficacy.

Yay (0)

Anonymous Coward | more than 4 years ago | (#28173581)

No more of this Florescent crap

less than a 60 watt bulb? (1)

wjh31 (1372867) | more than 4 years ago | (#28173593)

so... less than 60 watts?

"... and remaining much cheaper to produce." (1)

ridgecritter (934252) | more than 4 years ago | (#28173611)

Oh? Than what? Even after amortizing the capital and maintenance costs for the femtosec laser? 2x incandescent bulb efficiency puts it smack dab not as efficient as CFLs, and definitely not as efficient as LED lighting. Loses on lumens/$ to CFLs, as well. Jeez, it's amazing how many otherwise smart people either (a) don't appreciate the development distance between a cool lab demo and a commercial product, and/or (b) don't look over the hedge and see how much better some other tech is at meeting the need. Cool nanostructures and radiation enhancement effect, though - gotta give 'em that.

Re:"... and remaining much cheaper to produce." (0)

Anonymous Coward | more than 4 years ago | (#28173795)

It's surprising how many people dislike LED and CFL color spectra. Incandescents incandesce -- they are black body radiators, like the sun, and unlike CFLs, LEDs, and other sources of discrete light.

Yes, this is a big deal, especially since incandescent bulbs approach the efficiency of the inferior hippie bulbs.

shark (2, Funny)

Arimus (198136) | more than 4 years ago | (#28173625)

So does this mean every evil genius lair is now only complete with sharks with freekin' light bulbs on their heads?

So... (0)

Anonymous Coward | more than 4 years ago | (#28173627)

by unleashing "as much power as the entire grid of North America" we save 40 watts per bulb...

*golf clap*

Re:So... (0)

Anonymous Coward | more than 4 years ago | (#28173849)

Power and energy are not the same. Power is energy over time. A lot less than 4 joules is used, in a few femtoseconds.

Brillant.

Paging Al Gore.... (0)

Anonymous Coward | more than 4 years ago | (#28173645)

Hello you there?... Pick up the phone

Im a true american! (1)

nickdc (1444247) | more than 4 years ago | (#28173751)

If my light bulb doesn't shine like a 60watt bulb and require the energy of a 100watt bulb, then I want nothing to do with it! God Bless America!

LEDs are the future (0)

Anonymous Coward | more than 4 years ago | (#28173831)

LEDs are the future, CFLs will dominate until the transition from incandescent to solid state happens. there are already some really good, bright, and efficient LED light bulbs out there. there are already incandescents that use 60 watts and produce the equivalent of I think its either 75 or 100 watt incandescent lights. 60 watts is still too much, it is not efficient.

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