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Lasik surgery

leah — Sun, 04 Jul 2010 22:57:37 +0000

If your vision’s blurring and you hate the idea of using glasses or contact lenses, you should consider Lasik surgery as an option. Short for Laser Assisted In Situ Keratomileusis, this walk-away procedure is used to treat near sightedness (myopia), far sightedness (hyperopia) and cylindrical (astigmatism) refractive errors.

Lasik is a walk-away surgery where the patient does not need to be hospitalised. Using a microkeratome, a cutting tool with a metal blade, a hinged flap in the cornea is cut. The flap is folded back and an excimer laser is used to reshape the cornea from the newly exposed surface. Then the flap is put back in place, resulting in a reshaped cornea that produces better vision.

To be suitable for traditional lasik surgery, a person should be 18 years old to ensures that the eye has matured and developed properly, must have a stable vision, should not have any concurrent eye infection, cataract or eye injury, should not have a thin cornea, and suffer from an autoimmune disorder.

The entire procedure takes 15 minutes and is almost painless. The cost of a lasik procedure ranges between Rs 30,000 and 45,000 for both eyes.

Blade-free lasik uses two lasers instead of one, with the first laser replacing microkeratome blade used in conventional surgery. Then second excimer laser is used to reshape the cornea. The blade-free technique makes surgical vision correction possible for people who have steep, flat or thin corneas and not suited for traditional lasik surgery.

NASA has recommended the blade-free procedure for its astronauts as it can withstand the toughest physical conditions, including high G-forces. The cost of a blade-free lasik is between Rs 90,000 -Rs 1 lakh for both eyes.

Avoid splashing water or rubbing the eyes for a few weeks after surgery. You also need to wear sunglasses when you step outdoors. Other than that, you can follow your normal routine from the very next day, with restrictions on TV-viewing or computer use.

Source : hindustantimes

Laser therapy may ease type of eczema

leah — Fri, 04 Jun 2010 00:49:37 +0000

(Reuters Health) – Laser therapy that delivers a concentrated beam of ultraviolet light may help ease a hard-to-treat form of eczema, a small study suggests.

Health

The study, published in the British Journal of Dermatology, compared the effects of laser therapy versus corticosteroid ointment in 13 patients with what is known as the prurigo form of atopic dermatitis.

Atopic dermatitis is a type of eczema, or skin inflammation, that arises from an allergic reaction; the prurigo form is marked by small, hard, intensely itchy nodules on the skin.

Only a small proportion of people with atopic dermatitis have the prurigo form, but the condition can be challenging to manage, according to Dr. Elian E.A. Brenninkmeijer, a dermatologist at the University of Amsterdam, in the Netherlands, and the lead researcher on the study.

The current findings, while based on only a small number of patients, suggest that when topical treatments fail to improve prurigo atopic dermatitis, laser therapy may be a suitable option, Brenninkmeijer told Reuters Health in an email.

Specifically, a device called the 308-nm excimer laser is approved in the U.S. for treating atopic dermatitis and certain other skin conditions, including psoriasis and vitiligo. It works by emitting a concentrated beam of ultraviolet B (UVB) light directly to patches of affected skin, avoiding the healthy surrounding skin.

UVB light has long been used to treat some cases of atopic dermatitis; it is thought to help by quelling the exaggerated immune response causing the skin inflammation. The purported advantage of the excimer laser over traditional UVB therapy is that it more precisely targets the problem areas of the skin.

However, there are only limited study data on the effectiveness of the laser therapy for atopic dermatitis, and almost nothing known about how it works for the prurigo form.

To investigate, Brenninkmeijer and his colleagues recruited 13 adults with atopic dermatitis and prurigo nodules on the upper or lower extremities on both sides of the body.

Over 10 weeks, the patients received twice-weekly laser treatments on one side of the body, and used prescription corticosteroid ointment — clobetasol propionate — on the other side of the body. Both the laser treatment and the ointment were applied directly to the prurigo nodules.

By the end of the treatment period, the study found, both therapies were similarly effective in reducing the number of skin nodules, inflammation and itchiness. All but one patient showed improvements; for three patients, the laser-treated side of the body showed greater improvements, while for four, the corticosteroid-treated side fared better.

However, the benefits of the laser tended to be longer lasting. Six months after treatment, eight patients had maintained a significant improvement on the laser-treated side, while only three showed similar results on the corticosteroid-treated side.

According to Brenninkmeijer, larger clinical trials are now needed to confirm the effectiveness of laser therapy for this form of atopic dermatitis, as well as its cost-effectiveness.

Topical corticosteroids have an obvious advantage in that they are inexpensive and convenient. But for people whose skin condition does not improve with topical treatment, Brenninkmeijer said, “the excimer laser might be a good alternative.”

The potential short-term risks of the laser therapy include burns (similar to a sunburn), blistering and skin darkening. Little is known about the possible long-term side effects, including whether there is any increase in skin cancer risk, according to Brenninkmeijer.

Researchers are still unsure whether traditional UVB therapy carries a heightened risk of skin cancer in the long term. It’s possible, Brenninkmeijer noted, that any such risk would be less with the excimer laser, since it targets only small areas of affected skin, but that remains to be seen.

SOURCE: here British Journal of Dermatology, online May 20, 2010.

Mapping Ancient Civilization, in a Matter of Days

leah — Thu, 03 Jun 2010 10:07:35 +0000

For a quarter of a century, two archaeologists and their team slogged through wild tropical vegetation to investigate and map the remains of one of the largest Maya cities, in Central America. Slow, sweaty hacking with machetes seemed to be the only way to discover the breadth of an ancient urban landscape now hidden beneath a dense forest canopy.

Even the new remote-sensing technologies, so effective in recent decades at surveying other archaeological sites, were no help. Imaging radar and multispectral surveys by air and from space could not “see” through the trees.

Then, in the dry spring season a year ago, the husband-and-wife team of Arlen F. Chase and Diane Z. Chase tried a new approach using airborne laser signals that penetrate the jungle cover and are reflected from the ground below. They yielded 3-D images of the site of ancient Caracol, in Belize, one of the great cities of the Maya lowlands.

In only four days, a twin-engine aircraft equipped with an advanced version of lidar (light detection and ranging) flew back and forth over the jungle and collected data surpassing the results of two and a half decades of on-the-ground mapping, the archaeologists said. After three weeks of laboratory processing, the almost 10 hours of laser measurements showed topographic detail over an area of 80 square miles, notably settlement patterns of grand architecture and modest house mounds, roadways and agricultural terraces.

“We were blown away,” Dr. Diane Chase said recently, recalling their first examination of the images. “We believe that lidar will help transform Maya archaeology much in the same way that radiocarbon dating did in the 1950s and interpretations of Maya hieroglyphs did in the 1980s and ’90s.”

The Chases, who are professors of anthropology at the University of Central Florida in Orlando, had determined from earlier surveys that Caracol extended over a wide area in its heyday, between A.D. 550 and 900. From a ceremonial center of palaces and broad plazas, it stretched out to industrial zones and poor neighborhoods and beyond to suburbs of substantial houses, markets and terraced fields and reservoirs.

This picture of urban sprawl led the Chases to estimate the city’s population at its peak at more than 115,000. But some archaeologists doubted the evidence warranted such expansive interpretations.

“Now we have a totality of data and see the entire landscape,” Dr. Arlen Chase said of the laser findings. “We know the size of the site, its boundaries, and this confirms our population estimates, and we see all this terracing and begin to know how the people fed themselves.”

The Caracol survey was the first application of the advanced laser technology on such a large archaeological site. Several journal articles describe the use of lidar in the vicinity of Stonehenge in England and elsewhere at an Iron Age fort and American plantation sites. Only last year, Sarah H. Parcak of the University of Alabama at Birmingham predicted, “Lidar imagery will have much to offer the archaeology of the rain forest regions.”

The Chases said they had been unaware of Dr. Parcak’s assessment, in her book “Satellite Remote Sensing for Archaeology” (Routledge, 2009), when they embarked on the Caracol survey. They acted on the recommendation of a Central Florida colleague, John F. Weishampel, a biologist who had for years used airborne laser sensors to study forests and other vegetation.

Dr. Weishampel arranged for the primary financing of the project from the little-known space archaeology program of the National Aeronautics and Space Administration. The flights were conducted by the National Science Foundation’s National Center for Airborne Laser Mapping, operated by the University of Florida and the University of California, Berkeley.

Other archaeologists, who were not involved in the research but were familiar with the results, said the technology should be a boon to explorations, especially ones in the tropics, with its heavily overgrown vegetation, including pre-Columbian sites throughout Mexico and Central America. But they emphasized that it would not obviate the need to follow up with traditional mapping to establish “ground truth.”

Jeremy A. Sabloff, a former director of the University of Pennsylvania Museum of Archaeology and Anthropology and now president of the Santa Fe Institute in New Mexico, said he wished he had had lidar when he was working in the Maya ruins at Sayil, in Mexico.

The new laser technology, Dr. Sabloff said, “would definitely have speeded up our mapping, given us more details and would have enabled us to refine our research questions and hypotheses much earlier in our field program than was possible in the 1980s.”

At first, Payson D. Sheets, a University of Colorado archaeologist, was not impressed with lidar. A NASA aircraft tested the laser system over his research area in Costa Rica, he said, “but when I saw it recorded the water in a lake sloping at 14 degrees, I did not use it again.”

Now, after examining the imagery from Caracol, Dr. Sheets said he planned to try lidar, with its improved technology, again. “I was stunned by the crisp precision and fine-grained resolution,” he said.

“Finally, we have a nondestructive and rapid means of documenting the present ground surface through heavy vegetation cover,” Dr. Sheets said, adding, “One can easily imagine, given the Caracol success, how important this would be in Southeast Asia, with the Khmer civilization at places like Angkor Wat.”

In recent reports at meetings of Mayanists and in interviews, the Chases noted that previous remote-sensing techniques focused more on the discovery of archaeological sites than on the detailed imaging of on-ground remains. The sensors could not see through much of the forest to resolve just how big the ancient cities had been. As a consequence, archaeologists may have underestimated the scope of Mayan accomplishments.

For the Caracol survey, the aircraft flew less than a half-mile above the terrain at the end of the dry season, when foliage is less dense. The Airborne Laser Terrain Mapper, as the specific advanced system is named, issued steady light pulses along 62 north-south flight lines and 60 east-west lines. This reached to what appeared to be the fringes of the city’s outer suburbs and most agricultural terraces, showing that the urban expanse encompassed at least 70 square miles.

Not all the laser pulses transmitted from the aircraft made it to the surface. Some were reflected by the tops of trees. But enough reached the ground and were reflected back to the airborne instruments. These signals, measured and triangulated by GPS receivers and processed by computers, produced images of the surface contours. This revealed distinct patterns of building ruins, causeways and other human modifications of the landscape.

The years the Chases spent on traditional explorations at Caracol laid the foundation for confirming the effectiveness of the laser technology. Details in the new images clearly matched their maps of known structures and cultural features, the archaeologists said. When the teams returned to the field, they used the laser images to find several causeways, terraced fields and many ruins they had overlooked.

The Chases said the new research demonstrates how a large, sustainable agricultural society could thrive in a tropical environment and thus account for the robust Maya civilization in its classic period from A.D. 250 to 900.

“This will revolutionize the way we do settlement studies of the Maya,” Dr. Arlen Chase said on returning from this spring’s research at Caracol.

Lidar is not expected to have universal application. Dr. Sheets said that, for example, it would not be useful at his pre-Columbian site at Cerén, in El Salvador. The ancient village and what were its surrounding manioc fields are buried under many feet of volcanic ash, beyond laser detection.

Other modern technologies, including radar and satellite imaging, are already proving effective in the land beyond the temples at Angkor, in Cambodia, and in surveys of the Nile delta and ancient irrigation systems in Iraq.

Laser signals breaking through jungle cover are only the newest form of remote sensing in the pursuit of knowledge of past cultures, which began in earnest about a century ago with the advent of aerial photography. Charles Lindbergh drew attention to its application in archaeology with picture-taking flights over unexplored Pueblo cliff dwellings in the American Southwest.

NASA recently stepped up its promotion of technologies developed for broad surveys of Earth and other planets to be used in archaeological research. Starting with a few preliminary tests over the years, the agency has now established a formal program for financing archaeological remote-sensing projects by air and space.

“We’re not looking for monoliths on the Moon,” joked Craig Dobson, manager of the NASA space archaeology program.

Every two years, Dr. Dobson said, NASA issues several three-year grants for the use of remote sensing at ancient sites. In addition to the Caracol tests, the program is supporting two other Maya research efforts, surveys of settlement patterns in North Africa and Mexico and reconnaissance of ancient ruins in the Mekong River Valley and around Angkor Wat.

Nothing like a latter-day Apollo project, of course, but the archaeology program is growing, Dr. Dobson said, and will soon double in size, to an annual budget of $1 million.

Source : The New York Times

Rain-making lasers could trigger showers on demand

leah — Thu, 03 Jun 2010 09:53:11 +0000

Lasers that stimulate condensation may help to induce rain artificially.

Zeeya Merali

The rain dance is getting a twenty-first-century revamp using laser technology. Optical physicists have demonstrated that shooting lasers into the air can trigger the formation of water droplets, a technique that could one day help to stimulate rainfall.

For more than 50 years, efforts to try to artificially induce rain have concentrated on ‘cloud seeding’ — scattering small particles of silver iodide into the air to act as ‘condensation nuclei’, or centres around which rain droplets can grow. “The problem is, it’s still not clear that cloud seeding works efficiently,” says optical physicist Jérôme Kasparian at the University of Geneva, Switzerland. “There are also worries about how safe adding silver iodide particles into the air is for the environment.”

Kasparian and his colleagues realized that there might be a more environmentally friendly alternative. Firing a laser beam made up of short pulses into the air ionizes nitrogen and oxygen molecules around the beam to create a plasma, resulting in a ‘plasma channel’ of ionized molecules. These ionized molecules could act as natural condensation nuclei, Kasparian explains.

To test whether this technique could induce droplets, the researchers fired a high-powered laser through an atmospheric cloud chamber in the lab containing saturated air (see video). They illuminated the chamber using a second, standard low-power laser, enabling them to see and measure any droplets produced. Immediately after the laser was fired, drops measuring about 50 micrometres wide formed along the plasma channel. Over the next three seconds, the droplets grew in size to 80 micrometres as the smaller droplets coalesced. The team’s results are published online in Nature Photonics¹.

Rainmaker

The next step for Kasparian and his team was to take the technique outside. The researchers already have experience using plasma channels to modify the weather: in 2008, they demonstrated that a beam from their high-powered portable ‘Teramobile laser’ could be fired into thunder clouds, triggering an electric discharge². The beam was able to reach its target without being deflected because the generated plasma channel modifies the speed at which light travels through air — slowing it down in the centre of the beam and speeding it up at the sides. This causes the beam to continually self-focus, helping it to maintain a high intensity across large distances (see ‘Bendy laser beam fired through the air’).

This time, Kasparian and his colleagues tested the Teramobile laser over a number of different nights and in various humidity conditions. Once again, they detected the amount of condensation induced by monitoring how much the light from a second laser was back-scattered by any droplets. In low humidity conditions, the Teramobile laser did not induce droplets. But when the humidity was high, the team measured up to 20 times more back-scattering after the Teramobile laser was fired than before, says Kasparian, suggesting that condensation droplets were forming.

Roland Sauerbrey, an expert on laser physics at the FZD Dresden–Rossendorf Research Centre in Dresden, Germany, says that the team has the potential to create a "breakthrough technology". "This is the first time that a laser has been used to cause condensation outdoors," he says.

However, the technique is still in its early stages. "We can only create condensation along the laser channel, so we won't be going out and making rain tomorrow," Kasparian notes. He and his team are now investigating whether they can create condensation over a wider area, by sweeping their laser across the sky.

Thomas Leisner, an atmospheric physicist at the Karlsruhe Institute of Technology, Germany, remains cautious about the feasibility of scaling up the technique in this way. "I am sceptical that this could be used to trigger rain on demand," he says. But he adds that the technology will have other uses. The researchers should now calibrate the relationship between the amount of condensation produced by the laser and the prevailing atmospheric conditions, he says. "They could use the amount of condensation produced by their laser as a measure of water saturation to help forecast the chance of rain," he says.

References
1. Rohwetter, P. et al. Nature Photonics advance online publication doi:10.1038/nphoton.2010.115 (2010).
2. Kasparian, J. et al. Opt. Express 16, 5757-5763 (2008). | Article

Source : naturenews

Tech Tips for Practicing Laserists

leah — Tue, 25 May 2010 02:56:59 +0000

Animator Blends Old And New
Interview with Carl Graves of Laser Force
By David Lytle

“Smooth as butter” is how Laser Force President Chris Stuart describes the work of his animation director, Carl Graves. The company entered the ILDA Awards competition for the first time this year and took a total of six awards in four categories, including ISP Cel Animation and both the ISP and non-ISP Graphic Module categories.

The company’s pieces incorporate traditional hand-drawn frames, plus computer-generated animations, plus a third style that blends together the best of both worlds. This fall, Laser Force will begin releasing a series of compact discs chock-full of their trademark animations. The discs will also include “Module Makers” designed to help laserists easily generate customized animations from the stock frames. Laser Force plans to release one new themed disc each quarter, with the first disc focusing on fire effects. The Laserist recently talked to Graves about his special style of animation. To see examples of the animation and learn more about the Module Makers CD series, visit the company’s Web site at: www.laserforce.net

Laserist: Tell me about what you call “computer-enhanced animation.” How is that different from the way animators usually work?
Graves: Traditionally, laser animation has been very heavy on the digitizing side. Take the example of 24 frames for one second of film or laser output. In the past, I would draw those 24 frames by hand, then hand them over to a digitizer and then possibly someone else to colorize those frames. With the approach I have now, I may only need to animate 6 of those 24 drawings, and maybe only digitize one or two of those drawings and then let the computer do the math between the motions.

Laserist: How is that different than just giving the computer a start position and an end position and then letting the computer do the in-between animation frames?
Graves: Animation requires a lot of fine touches to be appealing. If I give the computer a start point and an end point it will give me a flat move from A to B. But I may change an eyebrow or move a lip or bend a finger to give the animation that extra bit of realism, that extra bit of action and ultimately appeal. You cannot get that with straight computer animation. With computer-enhanced animation, you create key frames and digitize those keys and then let the computer blend those two key frames for you.

Laserist: I’ve seen your work and it seems amazing that you can get such fluid, lifelike motion by only drawing a handful of key frames. How is that possible?
Graves: It’s all in the pre-production. As any animator does, you examine the movement from A to B, every part, every detail—you figure the motion, the path, the flow and pretty much calculate it. But instead of drawing every frame of it you can create the same kind of appeal and flow within a computer enhanced model.

Laserist: How much time does this save?
Graves: You save a considerable amount in the digitizing and colorizing end. If you can imagine 24 frames dwindled down to maybe 2, that is a great cut and you might be able to eliminate colorizing all those frames as well. But, because it is so reliant on pre-production, it doesn’t necessarily save a lot on the animator’s time. You are still plotting, still drawing and you will do reference keys and rough drawings.

Laserist: What about the tools you use? I understand you mix and match between hand-drawn animation, computer enhanced animation, and full-on digital animation all within the same show.
Graves: It is a balance between all the tools. If I am doing something that is very cartoony—something that is slapstick—I might want to go for more of a traditional look and not even use computer enhanced animation because I can’t capture the exaggerated look I want. Exaggerated motion doesn’t necessarily need to be as smooth as butter, so you use a more traditional style of art work. If you want mathematically correct perspective images you will go with a platform like 3D Studio Max (a conventional computer graphics animation program). If you want to kind of juggle in between, I think that type of animation is perfect for computer enhanced animation. It is just a matter of applying the right tool for the right job.

Laserist: I understand that some of these modules incorporate several styles.
Graves: Yes, it depends on the project. Various scenes might require one tool versus another. You may do 80% of your show with traditional hand-drawn animation, 15% with computer-enhanced animation and maybe 5% with LCMax [a Pangolin plug-in that renders 3D Studio Max output in laser light].

Laserist: I understand Laser Force is working on a series of animations and graphics that will be available for sale. Tellus about the additional tools these CDs will include to help people expand on the images.
Graves: Well, let’s say you are looking at a new or intermediate Pangolin user who generally will purchase graphics from another company and probably never use a lot of the tools that could possibly save them time or money. What I hope to do with Module Maker is not only offer great frames, but also include tips for Pangolin Showtime effects along with tutorials that help you get better use out of the equipment you have. It’s a whole suite of show-building materials that helps minimize production time.

Laserist: Can you give me a couple of examples of the effects in Showtime they might use?
Graves:For example, let’s say you want to create a star field moving through space. That is a very difficult thing to do by hand. You could do it on the computer and make that happen, but you might want some variations. You might want to go into a warp or you might want to pull out of a warp or slow it down or even change angles. Showtime effects can help do that without creating separate animations. You can change perspective, change scale, change position and add certain accelerations and decelerations within Showtime to achieve a different look. And most of these things we will show you how to do on the disk

Laserist: You aren’t afraid of giving away trade secrets, are you?
Graves: This is a service. It is something that we wish to share because of our passion for it, for the quality level that we wish to achieve. And it keeps us doing something we love and we have fun doing it, so I don’t think we are giving away too many trade secrets. Besides, when you boil it all down, it’s creativity and imagination that are most important.

Laserist: Let’s wind up here on the big picture. A lot of people look at lasers and they see them as a poor stepchild to traditional cel animation found in film and video. Critics don’t see laser displays on par with other forms of animation. How do you feel about that?
Graves: When I first started in the industry, I did share that opinion. I started in the traditional fields of animation, so doing lasers was really kind of an awkward thing. But the more I learned and the more I saw, I began to realize how it [laser display] really does the same things as traditional animation. You are not going to get the mega budgets for it, but you still get a lot of the same audience appeal. You can reach out and touch people in a variety of venues with lasers. It is more of a—I don’t know what the word is I am looking for— it’s a unique connection with the audience. I don’t think it pales in any way to other forms of animation. You are still communicating and you are still entertaining.

Robot With Laser to Zap Weeds Automatically in Chemical Free Control of Pesky Plants

leah — Sun, 09 May 2010 22:32:16 +0000

No more chemicals for fighting weeds in professional gardening! A fully automated unit drives over a field, a camera recognizes weeds sprouting up and a laser beam takes care of the rest. This science-fiction scenario is actually being researched at the Zentrum Hannover eV (LZH) and the Institute for Biological Production Systems (IBPS) at the Leibniz University Hannover.

Working sketch of the laboratory set-up for weed control using the laser. Image processing plants recognizes which plants are good and which are weeds, and aims the laser only at the weeds.

Image credit: Leibniz University Hannover/ Laser Zentrum Hannover eV

The main goal of the project supported by the German Research Foundation (DFG) is non-chemical weed control, one of the main goals of ecological planning and effective production. The basic idea is similar to flame weeding, in which heat is used to eliminate the weeds. However, this method burns out everything under the flame, and it is neither precise enough nor can it be automated. In comparison, a laser beam is precise and can be used to hit a sprouting weed, not affecting the plants around the weed. And “laser weeding” can be automated.

“The plans and laser experts have already carried out feasibility studies concerning first laser-assisted weeding” explains Christian Marx from the LCH. ”The laser prevents weeds from growing the young, but the reasons for this effect are not yet fully understood.”

That is the reason why researchers in this project will first develop a weed damage model, in which the effects of the laser beam (output, wavelength, energy, beam shape, etc.) on different kinds of weeds will be investigated. Based on this information, a laser system will be set up in the next step, an image processing system will be developed, which recognizes weeds on different terrains, and defines where the laser beam should be Aimed, to be most effective.

Following this, the laser system and the image processing system will be integrated into a pilot unit, which will first be tested under simple, controlled laboratory conditions. Then the system will be tested in a greenhouse, before field experiments are carried out. Laser safety is also a concern, for the lab, greenhouse and field investigations.

The project will run until the beginning of 2012, and aims at weed control without the use of chemical for professional gardening. ”The system is too complicated for use at home,” adds Marx. ”I’ll still have garden weeds to pull up by hand in my own (garden).”

LOBO’s Interactive Laser Show

leah — Thu, 29 Apr 2010 09:10:11 +0000

LOBO electronic recently premiered its first interactive laser show at Germany’s Holiday Park. LOBO’s Alex Hennig said the show worked better than expected, with thousands of audience members eagerly responding to the commands of a laser-projected girl.

The show, performed this summer in the theme park’s Aqua Stadium, featured a floating water screen, four laser systems, and 18 fog generators. The laser-projected girl gave the audience instructions (such as waving hands, clapping, and singing along to the music). “Surprisingly, the audience really followed even the most demanding actions and this concept really had a booster effect,” said Hennig. To add more excitement, the audience was given small battery-powered fiber lamps that turned the audience area into a sea of moving lights.

Source : The Laserist

World’s largest laser fires up for attempt to build new star on Earth

leah — Thu, 29 Apr 2010 09:04:22 +0000

SCIENTISTS are using the world’s largest laser in an attempt to build a star on Earth.

The laser at the Lawrence Livermore National Laboratory is roughly the size of three American football fields, and those in charge of it aren’t joking when they say they’ll create a tiny sun in the next few months.

It’s called the National Ignition Facility and it’s all about finding the holy grail of energy production – nuclear fusion – a high-energy reaction that would theoretically provide limitless energy for humanity.

In a nutshell, the laboratory hopes to split its laser beam up into 192 beams, then fire them at a tiny target wrapped in gold that’s smaller than a fingernail.

Nerd alert – inside the target there’s a couple of reactive hydrogen isotopes, so you know what comes next.

The heat from the laser will fuse those isotopes together in reaction that at 100 million degrees Celsius, more than five times hotter than the centre of the sun.

There is a slight radioactive danger, but the lab has encased the facility in concrete walls that are two metres thick, just in case.

But the payoff is that if the isotopes fuse, the tiny star will emit enough energy to power the Earth.

That is, for the 200 trillionths of a second that it survives.

“It’s the most fundamental energy source in nature,” project manager Bruno Van Wonterghem told CNN.

The only fuel it requires is seawater, the source of the aforementioned isotopes.

If it’s successful, the laboratory hopes the project, which has so far been five years in development and cost more than $2 billion, will deliver useable outcomes within 20 years.

“This is something you’re going to tell your grandchildren about,” Mr Van Wonterghem told CNN.

“It’s like standing on the hill watching the Wright brothers’ plane go by.”

Source : news.com.au

Vancouver 2010 Olympics – nightly laser shows

admin — Tue, 02 Feb 2010 06:14:32 +0000

Laser Waterworks Show

Starts Feb 12:

Join friends or family at False Creek to see the nightly laser light shows which will take place at the LiveCity Yaletown location. A large pipe in False Creek will stream water high into the air providing the backdrop for what will become a vivid backdrop to all the excitement. Across False Creek you will be able to see the Olympic Athlete’s Village. The City of Vancouver says the fireworks and water show will start in the late evening, but they don’t provide a start time. Once we have this, we’ll post it here. For a map showing you how to get to David Lam Park, click here.

State Patrol Airplane Hit with Laser

admin — Sun, 08 Nov 2009 02:54:37 +0000

Seattle-Tacoma: The FBI and Transportation Security Administration are investigating complaints that someone has been pointing lasers at airline pilots as they approach Seattle-Tacoma International Airport.

To illustrate the problem, the State Patrol today released this video of a laser pointer being aimed at a pilot flying at 2,000 feet.

On Jan. 29, troopers in a State Patrol airplane were targeted with a laser pointer in the Fife area. The airplane was initially hit with a green laser and the tactical flight officer (TFO) was able to turn the airplane’s Forward Looking Infrared (FLIR) camera on the residential area where the initial laser originated. The individual soon tried it again, and the TFO was able to identify the individual’s location.

The airplane flew over the residence until Pierce County sheriff’s deputies were able to make contact with the individual.

The suspect was not arrested at the scene. However, a person can be indicted under the Patriot Act for interfering with aircraft pilots, and charges by the Pierce County Prosecutor’s Office are considered pending and should be filed by the end of this month, the State Patrol said.