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Oxford Professor Chunlei Guo, seen here, has figured out a way to use a laser to make incandescent lightbulb filaments to be much more efficient, a process that should be relatively cheap.  (Source: Photobucket)
New approach offers more pleasant light of traditional bulbs without the energy guilt

Thanks to a bit of ingenuity, Chunlei Guo, associate professor of optics at the University of Rochester, and his assistant Anatoliy Vorobyev have been able to squeeze out fluorescent-like energy performance from an incandescent light bulb.  The breakthrough boils down to a laser treatment of the bulb's tungsten filament, a processing step which could one day become a standard in the light bulb industry.

Traditionally, incandescent light bulbs provide more pleasant light, however they lack the efficiency of fluorescent designs.  The new bulb offers the brightness and color of a 100 watt incandescent bulb while using less than 60 watts.

The key is to blast the tungsten filament with an ultra-fast, ultra-powerful laser, which creates beneficial nanostructures on the metal's surface.  Describes Professor Guo, "We've been experimenting with the way ultra-fast lasers change metals, and we wondered what would happen if we trained the laser on a filament.  We fired the laser beam right through the glass of the bulb and altered a small area on the filament. When we lit the bulb, we could actually see this one patch was clearly brighter than the rest of the filament, but there was no change in the bulb's energy usage."

The pulse lasts a mere femtosecond, and delivers as much power as the entire grid of North America into a needle point size spot.  Serendipitously, this strange treatment yields nanostructures and microstructures which turn a low-wattage incandescent light bulb into a high brightness one, while preserving its energy sipping character.

The incredible discovery was made after Professor Guo tinkered with the reverse phenomena -- a laser processed metal that was incredibly good at capturing light, making it almost a perfect black.  He figured that if this was possible, the reverse -- a material giving off light much more efficiently -- was also probable.  Professor Guo describes, "There is a very interesting 'take more, give more' law in nature governing the amount of light going in and coming out of a material.  We knew it should work in theory, but we were still surprised when we turned up the power on this bulb and saw just how much brighter the processed spot was."

The process can also tune the color of the bulb.  By controlling the pulse, the resulting nanostructures are modified in a predictable way, in turn modifying the wavelength of the emitted light.  Professor Guo has demonstrated blue, golden, and gray designs, in addition to black, white, and the base yellow.  The team has even made filaments able to emit polarized light without efficiency-reducing filters.

Funded by the U.S. Air Force Office of Scientific Research, Professor Guo continues to explore what kind of additional changes he can invoke with the laser.  And given that the laser he's using can run off a wall socket, there's hope that the discoveries he takes can be ported to production.  While materials changes are frequently expensive, this breakthrough would only need capital investments for the laser, which is reusable.  Thus it could deliver these super-bulbs at a reasonable price.

The new research is detailed in a paper, appearing in the journal Physical Review Letters.

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Does that make sense?
By Nomarian on 6/2/2009 8:35:35 AM , Rating: 2
LOL. So let me get this straight. We take all the power in the North American electric grid to blast the filament in a light bulb to make it use 60 watts instead of 100 watts? Hilarious!

RE: Does that make sense?
By Brandon Hill on 6/2/2009 8:38:02 AM , Rating: 2
You're correct -- it is quite comical to say the least :)

RE: Does that make sense?
By theapparition on 6/2/2009 9:35:46 AM , Rating: 5
Quite comical you didn't get that little part about the femtosecond thing. :P

RE: Does that make sense?
By pmonti80 on 6/2/2009 8:41:20 AM , Rating: 2
That's not very efficient. I though the new low energy bulbs could do the equivalent of 100W with only 20W.

RE: Does that make sense?
By Yojimbo on 6/2/2009 12:17:07 PM , Rating: 2 26 watt compact fluorescent is rated at 100-watt equivalent. The article says with energy efficiency similar to fluorescent bulbs, but "less than 60-watts" for a 100-watt equivalent is not close.

RE: Does that make sense?
By ArcliteHawaii on 6/3/2009 5:20:07 AM , Rating: 3
Well, there could be some benefits, even if it used more power than a CF. Incandescents are much cheaper to make, although I have no idea how much this treatment adds. Also, for places where the lightbulb goes off and on a lot, like the bathroom, CFs wear out much more quickly. And CFs contain mercury, which is highly toxic if the bulb is broken or ends up in a landfill. And the light from incandescents is warmer and easier on the eyes.

RE: Does that make sense?
By Dribble on 6/2/2009 1:28:13 PM , Rating: 2
Not only that they last about 5 times as long.

Now you can get fluorescent bulbs in all sorts of shades of white, that are the same size as an incandescent bulb and that can be dimmed something like this is basically a non starter.

The actual next gen bulb will use LED's and take about 10W for the equivalent of a 100W.

RE: Does that make sense?
By Jimbo1234 on 6/2/2009 1:49:10 PM , Rating: 1
There are dimmable CF bulbs. Also, Halogen bulbs are on the order of efficiency of these new bulbs. So this new bulb is worthless.

RE: Does that make sense?
By Samus on 6/2/2009 4:43:49 PM , Rating: 2
Halogen bulbs are anything but efficient. They run extremely hot as well. The only benefit they offer is a longer lifespan. For the amount of lumens they put out, they use just about the same wattage as incandecent.

As said, CFL and LED is the future. Although, I've always been a fan of HID, but metal halide and HPS bulbs aren't cheap. But the light output is beautiful, they're fairly energy efficient for the lumens and they have a decent lifespan (10,000-20,000 hours before they begin to fade)

RE: Does that make sense?
By Alexvrb on 6/2/2009 6:35:36 PM , Rating: 2
Yeah HIDs are still the king of automotive headlamps. Some LED setups are pretty nice, but they make the already-costly HIDs look downright cheap. Plus you can fit an HID anywhere you can fit an existing halogen bulb (assuming you have room for a couple small inverters), but the same can not be said of an array of bright LEDs.

RE: Does that make sense?
By Jimbo1234 on 6/2/2009 8:17:33 PM , Rating: 2
HIDs last essentially the lifetime of a car. On one of my cars, they are as good as new with 120,000 miles on it. The other car needed one replacement at 85,000 miles. Try to find a car on the road with a burned out HID (Xenon) bulb (not that fake garbage).

RE: Does that make sense?
By djc208 on 6/3/2009 10:08:54 AM , Rating: 2
But what did that replacement cost? The technology is great but, like these other exotic light sources, expensive should they fail or be damaged.

RE: Does that make sense?
By Jimbo1234 on 6/2/2009 8:15:14 PM , Rating: 2
I recently purchased halogen bulbs for use at home. They use about 20% less energy than a standard incandescent bulb. You're statement about halogen bulbs being anything but efficient is false.

RE: Does that make sense?
By Diesel Donkey on 6/3/2009 12:18:12 AM , Rating: 4
The new bulb you speak of has barely been discovered. Give it a little time! Besides this is a potentially important scientific discovery in its own right with possible uses outside traditional light bulbs.

By inperfectdarkness on 6/5/2009 4:03:29 PM , Rating: 2
+ eleventy billion.

led's last exponentially longer than cfl or incandescent and are stratospherically more efficient.

i can't wait for the day i can ditch all of the traditional lighting devices/lamps for all LED lighting (and not just some tacky rope lights)

RE: Does that make sense?
By Regs on 6/2/2009 8:49:26 AM , Rating: 2
I guess when you calculate in that fluorescent light bulbs are usually on a good percentage of the day for hundreds of hours of usage. These lasers also pulsate in durations of picoseconds, but I would not know how much power they would consume because would depend on the frequency of the pulsation.

RE: Does that make sense?
By Syzygies on 6/2/2009 9:20:26 AM , Rating: 2
You're forgetting the duration. If I offered you a trillion dollars per second to elaborate, with a 10 femtosecond limit, how much money is that?

The article nevertheless spins these numbers a bit. An actual quote from the paper, describing their laser power:
Our experiment employs two ampli?ed Ti:sapphire fs laser systems, one high-power system, and one high- repetition-rate system. The high-power fs laser system gen- erates 65 fs pulses of an energy of 1 mJ/pulse at 800 nm with a 1 kHz repetition rate, while our high-repetition-rate laser system generates 60 fs pulses of an energy of 4uJ / pulse at 810 nm with a 273 kHz repetition rate.

RE: Does that make sense?
By ralith on 6/2/09, Rating: 0
RE: Does that make sense?
By menace on 6/2/2009 12:12:27 PM , Rating: 1
You make several errors. First you plug "1000W" which is a power quantity into a variable you call "Energy". Then you divide that by time (which comes out to units of W/s, i.e. "rate of change of power") and come up with a result in units of energy (Joules = Watt-Seconds) and store the result into a variable called "Power". Did you even pass high school physics?

RE: Does that make sense?
By ralith on 6/2/2009 4:49:22 PM , Rating: 5
I swapped joules and watts. I have always mixed up joules and watts. On top of that it apparently isn't clear to everyone that at steady state a 1000 watt microwave is consuming 1000 joules per second so I won't use appliance examples this time.

The whole point of the previous post is to show that energy doesn't have to be high to get a very large power if the energy is delivered in a very small time. As is explained in this pretty good definition of power:

In physics, power (symbol: P) is the rate at which energy is transmitted, or the amount of energy required or expended for a given unit of time.
taken from

So even if the energy delivered is .001 J but the time required to deliver it is a femto second the resulting power is 1 terrawatt.

Also, your post was wrong energy does not equal power minus time it equals power multiplied by time. See the link.
Did you even pass high school physics?
I did. Did you?

RE: Does that make sense?
By rbfowler9lfc on 6/2/2009 9:37:23 AM , Rating: 3
Absolutely. No reactive power, no harmonics back on the grid. And as the article says, the laser doesn't reduce power consumption, it makes filaments emit brighter light, so a 40W tuned-bulb would emit more lux than a standard 40W bulb.

RE: Does that make sense?
By pmonti80 on 6/2/2009 11:17:04 AM , Rating: 2
But much less light than a low energy bulb of the same 40W.

RE: Does that make sense?
By Calin on 6/2/2009 10:06:50 AM , Rating: 2
Yes, and it took just 10^-15 seconds to do this. Assuming you are not making a spot but all the filament, add three orders of magnitude for all the surface
So, with all the power use of the US of A, you could make about 1 million million light bulbs a second.

RE: Does that make sense?
By manofhorn on 6/2/2009 11:43:34 AM , Rating: 2
Yea, it's all that power for 10^-15 seconds. sooo... not very much power.

RE: Does that make sense?
By Diesel Donkey on 6/3/2009 12:16:31 AM , Rating: 3
No, it's a huge amount of power, but not that much energy.

RE: Does that make sense?
By grandpope on 6/2/2009 3:24:13 PM , Rating: 2
And given that the laser he's using can run off a wall socket

So, this guy is stealing all the power in North America through his wall socket for a femtosecond?

I would like to see that 'as much power as the entire grid of North America' comment stricken from the record, your honor.

In conclusion, what is a Wookie doing on Endor? It does not make sense!

Does it work for the human body?
By borowki2 on 6/2/09, Rating: 0
RE: Does it work for the human body?
By melgross on 6/2/2009 12:34:17 PM , Rating: 4
Yes, you are.

By rbfowler9lfc on 6/2/2009 11:29:33 PM , Rating: 4
I have improved my eyes' capabilities ten-fold since I applied a powerful laser beam on them.... =)

CFL Contents
By SiliconJon on 6/2/2009 9:40:01 AM , Rating: 4
Oh how often do we take one step forward and two back.
All Fluorescent Lamps and Tubes Should Be Recycled or Disposed as Hazardous Waste

What are we going to do with all these CFL's when we're done with them? Toss them in the garbage - where the mercury and lead and [what else?] can wind up in our water tables.

I'm glad to see some progress still being pursued as there's plenty of room for further progress.

RE: CFL Contents
By msomeoneelsez on 6/2/2009 11:16:59 AM , Rating: 2
What would be the alternative? Keep producing more CFL's while we throw them out... well, only when they are done being used? Wait... doesn't that mean all of them anyways?

Should we use the new process in treating the incandescent bulbs, CFL production will decrease, and eventually stop should the new process be good enough.

RE: CFL Contents
By melgross on 6/2/2009 12:45:50 PM , Rating: 1
Even if this works, something about which I have doubts, it will take years until they get into production.

This is really a very backwards thing. At best, it will gain a 40% increase in efficiency, which will still leave them inefficient, while compact fluorescents are three times as efficient as these will be. These will also have a life no longer than any other incandescent bulbs, and perhaps less.

If this had been on the market five years ago it might have been different. But they will be illegal by 2013 anyway, when new laws about lamp efficiency come out here. They are already too inefficient for several countries.

The future of lighting is LED, not an ancient incandescent technology invented in the 19th century.

As far as mercury goes, compact fluorescents have very tiny amounts. There are ways to dispose of them, if people really wanted to. Many companies will take them back. They are later processed.

Do you take all of your old batteries and dispose of them properly?

No? I didn't think so.

U.S. Air Force Office of Scientific Research?
By masouth on 6/2/2009 3:11:19 PM , Rating: 1
Am I in the minority that read who is funding this research? I can't see where any other comments addressed this yet is seems quite relevant.

U.S. Air Force Office of Scientific Research: AFOSR's mission is to discover, shape, and champion basic science that profoundly impacts the future Air Force

Is this research primarily intended to directly benefit the public at large? Doubtful

Should this technology eventually prove viable will it trickle onto the the commercial market and into our lives as so much other military research has eventually? Sure it's possible.

Many of these comments would imply many people can't see far enough beyond the screen in front of their face to realize that the research may have uses outside of their reading lamp.

Specific applications, I don't know...but I am sure there are times/places where fluorescent lighting does not work better/make more sense.

Then again it could also just be more government waste...meh

By knutjb on 6/2/2009 8:52:28 PM , Rating: 3
The military has funded college research for decades, just like many companies. Look at all the amazing things that come out of schools. When using an educational institution you have fresh thinking not usually associated with the corporate world. Also this form of research is usually the most economical since the students don't require a pay check and the professors already get a pay check along with existing facilities, etc... All parties get a benefit. When a discovery is patented the research sponsor gets a big cut of those funds, i.e. you the tax payer. FYI shows what NASA research has translated into consumer use.

I do agree with your observation of the short sighted comments above, it's more the making an incandescent light bulb more efficient. It's where this research started by laser treating metals to change the surface appearance i.e. a nearly black metal panel, a band width specific light bulb, they don't require a nuke power plant to power the laser therefore easy to implement.

What was missed by the bulk above is wasn't what they have done to date, it's what might be treated that holds interesting promise.

Most of what is created for the military does show up in the civilian world. i.e. a small pre-made instantly adjustable tourniquet, a powder that stops severe bleeding instantly, GPS, satellite communications...

By IH8U2 on 6/3/2009 8:05:44 AM , Rating: 2
Is this research primarily intended to directly benefit the public at large? Doubtful

Not really, you are using something that was developed by the DoD, on an almost daily basis. That is the Internet (no it wasn't made by Gore). Yes it may take a while for it to trickle down, but if there are real-world benifits to these bulbs, something I seriously doubt. They should come out. But as LED's are still more useful, use less power, and outputs more light.

The easy answer, you want to save money. Turn off the light when you are not in the room. Turn off the TV. And turn down the heat/open a window (depending on weather).

This probably isn't the answer
By barrychuck on 6/2/09, Rating: 0
By barrychuck on 6/2/2009 9:06:02 AM , Rating: 2
Even better is the colors he can make. Can someone explain grey light? Yellow and blue, I could see easily resulting from the process, but grey, and then polarized light? Quartz glass will polarize light, so what's to say the filament is doing this and not the outer glass.

I would have more faith in this if he published the microstructure change, and the theory of how that effects quantum light output. Some picture of before and after of the filament with an electron microscope.

By melgross on 6/2/2009 12:31:49 PM , Rating: 3
No. Your understanding of this is flawed.

IF, it just evaporated some metal off the filament, and made a thinner part, the resistance would INCREASE, not decrease.

Don't you know this? It's electricity 101.

What he said was that it created "structures". What was meant was that the metal moved into a different shape.

My understanding of that difference is that tiny raised "whiskers" and such were created, which increased the surface area, thus giving off more light, but not changing the effective diameter of the filament, and so not changing the resistance.

Therefor, the bulb would would consume the same amount of current while giving a greater light output, increasing the efficiency.

How long these tiny structures would last in actual long term use is a different question. They may burn off after a relatively short time. That would result in a shorter lifetime for the bulb, as that's what causes bulbs to burn out. Also, bulbs get a coating of metal on the inner surface over time from the burnt off filament, and this causes the effective light output to lessen. this could happen here even faster as those tiny filaments burn off quickly.

Overall, this concept is still in development for good reasons. It may never become practical.

"Ultra-fast" laser?
By jaericho on 6/2/2009 9:23:44 AM , Rating: 1
Is it going 1.0001c? 1.1c? 2c? Warp 9?

I read that sentence and laughed.

RE: "Ultra-fast" laser?
By theapparition on 6/2/2009 9:47:03 AM , Rating: 4
Generally that term is used to describe lasers that can produce a high energy short duration burst, not all are capabable of that.

Laser light timing
By melgross on 6/2/2009 12:56:04 PM , Rating: 2
You guys are making a big mistake calculating the laser timing.

The one very short burst you are all arguing about was for just making that one tiny spot in the filament more efficient. In order to do the same to the entire filament will require the pulses to be continued long enough to rework the entire filament, which once unwound, is pretty long.

This is another reason why this is just a lab experiment right now. It could take thousands of times as much energy to do this for one bulb as the experiment needed. Re-read that part carefully. Nowhere do they say that they've actually produced entire bulbs. They've produced "filaments". How long are they? .25"? They are extrapolating from their experiments to what they "hope" would be an actual product.

By ggordonliddy on 6/2/2009 11:15:06 PM , Rating: 2
Discussion points, please?

Wow or Meh?
By kapauldo on 6/10/2009 12:21:03 PM , Rating: 2
(linkback) Wow! or Meh? Laser blast makes 60W bulb burn as bright as 100W bulb [VOTE] -

“Then they pop up and say ‘Hello, surprise! Give us your money or we will shut you down!' Screw them. Seriously, screw them. You can quote me on that.” -- Newegg Chief Legal Officer Lee Cheng referencing patent trolls

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