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Can Laser Treatment Rejuvenate the Incandescent Bulb?- more info on Laser Light Bulbs! June 9, 2009

Posted by Dr. Z Bulbs in light bulb, List Article, Theory for argument sake., Weird Bulb News.
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Zoinks! Its me Dr Z! The Light bulb lovin man. Lasers and Light Bulbs are two great tastes that evidentally taste great together. Could this be the revolution in lighting? Methinks LEDS are in for some serious competion if this pans out.
Dr. Z
Set Your Light Bulbs on Stun!

Set Your Light Bulbs on Stun!

 

light bulbThe battle of the light bulb may not be quite over. While traditional incandescents will soon be phased out in the United States and abroad, researchers are plugging away to create more efficient versions that comply with looming new standards — while also providing an alternative for consumers who find compact fluorescents objectionable [The New York Times, blog]. In one new study, researchers have demonstrated how an incandescent bulb can be modified to give out much more light without requiring more power.

Lead researcher Chunlei Guo and his colleagues were experimenting with the effect of ultrafast laser pulses on metals when they noticed that pulses lasting only a few femtoseconds–quadrillionths of a second–could fundamentally change the molecular arrangement of metals without melting them [ScienceNOW Daily News]. The laser blasts caused the metal to turn black, which boosted its ability to absorb light. Because the law of thermal radiation state that materials that can absorb a great deal of energy will also emit large amounts of energy, the researchers decided to see if their laser treatment would boost the light output of the metal filament in an ordinary light bulb.

They fired a femtosecond laser beam through the glass of an off-the-shelf incandescent bulb. As expected, the lightning-fast beam rearranged the molecules of the bulb’s tungsten filament, turning it dark black. But then, when the researchers turned the bulb on, the part treated with the laser shone considerably brighter than the rest of the filament [ScienceNOW Daily News]. When they gave an entire filament the laser treatment, an altered 60-watt light bulb glowed as brightly as a 100-watt bulb, but still used its normal amount of electricity.

The findings, which will be published in the next issue of Physical Review Letters, may not be ready for commercialization just yet, but Guo believes it would not be difficult for bulb companies to add a tungsten blackening step to the manufacturing process. “The implementation should be fairly straightforward,” he said [The New York Times, blog]. However, compact-fluorescent bulbs and light-emitting diode (LED) bulbs are already on the market, and research is continuing on how to make those technologies cheaper, more pleasing to the eye, and still more efficient, so the laser treatment may not be enough to give new life to the old-fashioned light bulb.

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Holy Lazer Light Bulbs Batman! Regular Light Bulbs Made Super-efficient With Ultra-fast Laser June 1, 2009

Posted by Dr. Z Bulbs in light bulb, List Article.
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Zoinks! Just when you thought incandescent light bulbs were out for the count, Lasers come to the rescue. Below is an article from Science Daily that talks about  super bulb!

Dr. Z

www.zbulbs.com

 

Ok Mr Y. Just hold that light bulb steady

Ok Mr Y. Just hold that light bulb steady

 An ultra-powerful laser can turn regular incandescent light bulbs into power-sippers, say optics researchers at the University of Rochester. The process could make a light as bright as a 100-watt bulb consume less electricity than a 60-watt bulb while remaining far cheaper and radiating a more pleasant light than a fluorescent bulb can.

 

The laser process creates a unique array of nano- and micro-scale structures on the surface of a regular tungsten filament—the tiny wire inside a light bulb—and theses structures make the tungsten become far more effective at radiating light.

The findings will be published in an upcoming issue of the journal Physical Review Letters.

“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,” says Chunlei Guo, associate professor of optics at the University of Rochester. “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 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 can radiate from the filament.

In 2006, Guo and his assistant, Anatoliy Vorobeyv, used a similar laser process to turn any metal pitch black. The surface structures created on the metal were incredibly effective at capturing incoming radiation, such as light.

“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,” says Guo. Since the black metal was extremely good at absorbing light, he and Vorobyev set out to study the reverse process—that the blackened filament would radiate light more effectively as well.

“We knew it should work in theory,” says Guo, “but we were still surprised when we turned up the power on this bulb and saw just how much brighter the processed spot was.”

In addition to increasing the brightness of a bulb, Guo’s process can be used to tune the color of the light as well. In 2008, his team used a similar process to change the color of nearly any metal to blue, golden, and gray, in addition to the black he’d already accomplished. Guo and Vorobeyv used that knowledge of how to control the size and shape of the nanostructures—and thus what colors of light those structures absorb and radiate—to change the amount of each wavelength of light the tungsten filament radiates. Though Guo cannot yet make a simple bulb shine pure blue, for instance, he can change the overall radiated spectrum so that the tungsten, which normally radiates a yellowish light, could radiate a more purely white light.

Guo’s team has even been able to make a filament radiate partially polarized light, which until now has been impossible to do without special filters that reduce the bulb’s efficiency. By creating nanostructures in tight, parallel rows, some light that emits from the filament becomes polarized.

The team is now working to discover what other aspects of a common light bulb they might be able to control. Fortunately, despite the incredible intensity involved, the femtosecond laser can be powered by a simple wall outlet, meaning that when the process is refined, implementing it to augment regular light bulbs should be relatively simple.

Guo is also announcing this month in Applied Physics Letters a technique using a similar femtosecond laser process to make a piece of metal automatically move liquid around its surface, even lifting a liquid up against gravity.

This research was supported by the U.S. Air Force Office of Scientific Research.