Godlike Productions - Conspiracy Forum
Users Online Now: 2,339 (Who's On?)Visitors Today: 1,412,241
Pageviews Today: 2,045,478Threads Today: 424Posts Today: 11,167
07:19 PM


Rate this Thread

Absolute BS Crap Reasonable Nice Amazing
 

The Miracles of Laser Technology

 
Divinity
Offer Upgrade

User ID: 464760
United Kingdom
07/20/2008 11:59 AM

Report Abusive Post
Report Copyright Violation
The Miracles of Laser Technology
A femtosecond = one millionth of a nanosecond or 10 -15 of a second and is a measurement sometimes used in laser technology.


CHIRPED-pulse amplification strikes again.

Using it in a high-peak-power mode, Laboratory scientists produced first the 100-terawatt laser and then the petawatt laser, opening up new opportunities for applying laser-matter interactions. Now a Livermore team has won an R&D 100 Award for applying chirped-pulse amplification in a high-average-power mode for cutting and machining materials. The system was developed for disassembling nuclear weapons components, but it has many other uses as well.

The team, led by Brent Stuart, illustrates Livermore's collaborative nature by combining research and development expertise from Laser Programs and Defense and Nuclear Technologies Directorates.

From Demilitarization to Dentistry
----------------------------------
By ionizing the material being cut--removing it atom by atom--the cutting technique allows precise machining of everything from steel to tooth enamel to very soft materials like heart tissue. Each pulse of this machining system is extremely short, lasting just 50 to 1,000 femtoseconds (or quadrillionths of a second). These ultrashort pulses are too brief to transfer heat or shock to the material being cut, which means that cutting, drilling, and machining occur with virtually no damage to surrounding material. Furthermore, this revolutionary laser can cut with extreme precision, making hairline cuts in thick materials along a computer-generated path.

In dentistry applications, the thermal nature of the conventional laser ablation process can heat and crack a tooth and produce a random-shaped hole within a large area of collateral damage.
In contrast, at the same ablation rate, Livermore's new laser precisely removes the material and leaves the surrounding areas in their original state (see a and b of the figure, below).

The ultrashort-pulse laser represents a major advancement in cutting technology. Conventional lasers, diamond saws, and water jets are used commercially for a variety of cutting and machining applications. But each one has drawbacks. None of them can achieve the precision of the femtosecond laser machine tool (0.1 millimeters), and most of them damage surrounding material to varying degrees. Because of these shortcomings, no commercial cutting system can be used on the range of materials or applications of Livermore's new tool.

Industrial lasers, which melt and boil material to remove it, are often used in precision cutting. The heat and shock cause considerable damage to the area surrounding the cut that can range from changes in the grain structure to cracking. The damage may extend from a few micrometers to several millimeters from the cut, depending on the properties of the material, the laser pulse duration, and whether a cooling method is used. Very tiny structures only a few tens of micrometers in size, such as biological tissue or semiconductor devices, are extremely fragile. Even the slightest thermal stress or shock creates intolerable collateral damage.

These conventional cutting methods also leave slag around the cut. When material is vaporized, some of it is deposited on the walls or upper surface of the cut. This residue reduces the quality of the cut and the efficiency of the cutting system.

With each short pulse of the Laboratory's new laser cutter, material is heated to temperatures far beyond the boiling point, producing an ionized plasma, while leaving surrounding material cool. The pulse deposits its energy so quickly that it does not interact at all with the plume of vaporized material, which would distort and bend the incoming beam and produce a rough-edged cut. The plasma plume leaves the surface very rapidly, ensuring that it is well beyond the cut edges before the arrival of the next laser pulse. And because only a very thin layer of material is removed during each pulse of the laser, the cut surface is very smooth and does not require subsequent cleanup (see c and d of the figure, below).

Removal of minimal amounts of material makes this new cutting system useful for processing extremely valuable or hazardous materials. If the cutting is done in a vacuum, better than 95% of the removed material can be recovered.
Another Livermore team is building a high-powered femtosecond machining system for the Department of Energy's Y-12 Plant at Oak Ridge, Tennessee, one of this country's primary manufacturers of nuclear weapon components. A second unit at Livermore will be used as engineering support to the Y-12 unit. The high precision of this cutter will maximize the plant's ability to reuse high-value components and minimize the amount of waste generated during the cutting process.

Livermore is studying the use of the Femtosecond Laser to machine high explosives for experiments at its High Explosives Applications Facility. Because so little energy or mechanical shock is transferred to the part being machined, the team has demonstrated that materials such as high explosives or parts containing high explosives can be cut without danger of detonation. The team is also working on the design of a system for demilitarizing chemical weapons.

Other potential applications abound. Using the laser as a surgical tool for soft tissue has already been discussed in Science & Technology Review (October 1995). A semiconductor device producer is exploring the use of the unit for cutting high-value semiconductor wafers. Other major U.S. manufacturers are looking into incorporating femtosecond machining systems into their production lines. In manufacturing, new materials are constantly appearing, and the features on all kinds of devices are becoming smaller and smaller. The femtosecond machining system may be the most effective way to respond to both challenges with its high precision on all materials regardless of composition.

--Katie Walter

[link to www.llnl.gov (secure)]

cosmicdonu
"Aether is a Quantum 2 Spin Rotating Magnetic Field that encapsulates Primary Angular Momentum and via Tensegrity forms Matter with resulting Quantum 1/2 spin.

PHI is the direct result and first Ratio produced by this arrangement as it Cycles." Junglelord, www.thunderbolts.info

"It's never too late to have a happy childhood" - Ahim-sa

"Thought being a given is the first assertion of self-awareness; the remaining truth is simply "I am, therefore there is". Self and other, subject and object." Eyeam

"Remember me as I AM." My Brother
Divinity (OP)

User ID: 464760
United Kingdom
07/20/2008 12:05 PM

Report Abusive Post
Report Copyright Violation
Re: The Miracles of Laser Technology
How can the scientific standard model now defend their stance that 'nothing travels faster than the speed of light'?


[link to physicsworld.com]

Beating the femtosecond limit

The quest for ever-shorter laser pulses inevitably results in each pulse containing fewer and fewer oscillations of the laser field. Indeed, the shortest visible and infrared laser pulses are typically just a few femtoseconds (10-15 seconds) in duration and contain just a few cycles of the laser field. However, there is a need for even shorter pulses to study fundamental physical, chemical and biological processes on shorter and shorter timescales.

Moreover, many applications require photons with higher energies, so there is a corresponding need for ultrashort pulses at shorter wavelengths in the extreme ultraviolet and X-ray regions of the spectrum. Ferenc Krausz of the Technical University of Vienna and co-workers in Germany and Canada have now taken a major step in this direction (M Drescher et al 2001 Science Express 1058561).

They used a technique known as 'high-harmonic' generation to convert a 7 femtosecond infrared pulse into a 1.8 femtosecond X-ray pulse. In harmonic generation a large number of photons are combined in a noble gas - the Vienna team used neon - to create a single photon with a correspondingly reduced wavelength. By filtering the harmonics, it is possible to control the duration and wavelength of the X-ray pulse. Krausz and co-workers used such a pulse to study an laser-induced energy shift in krypton atoms with a time resolution that was shorter than a single cycle of their laser source (which lasts 2.6 fs).

Physicists may be able to use the new technique to study processes that occur on sub-femtosecond timescales such as inner-shell phenomena in atoms and ionization via 'optical tunnelling'. Drescher and colleagues are optimistic that their discovery will pave the way for ultrafast spectroscopy - the study of processes that take place on timescales of just attoseconds - 10-18 seconds.

Over the last four years, other groups have produced laser pulses with durations of around 10 femtoseconds using the high-harmonic method. However, the light in these pulses had longer wavelengths - in the visible and near-infrared regions of the spectrum. These pulses could not be shortened further because they were already approaching the fundamental lower limit for light of these wavelengths.


[link to physicsworld.com]
"Aether is a Quantum 2 Spin Rotating Magnetic Field that encapsulates Primary Angular Momentum and via Tensegrity forms Matter with resulting Quantum 1/2 spin.

PHI is the direct result and first Ratio produced by this arrangement as it Cycles." Junglelord, www.thunderbolts.info

"It's never too late to have a happy childhood" - Ahim-sa

"Thought being a given is the first assertion of self-awareness; the remaining truth is simply "I am, therefore there is". Self and other, subject and object." Eyeam

"Remember me as I AM." My Brother
Anonymous Coward
User ID: 422730
Australia
07/20/2008 02:41 PM
Report Abusive Post
Report Copyright Violation
Re: The Miracles of Laser Technology
bump
Anonymous Coward
User ID: 411199
United States
07/20/2008 09:51 PM
Report Abusive Post
Report Copyright Violation
Re: The Miracles of Laser Technology
I hadn't really thought of the implications of an ultraviolet or x-ray laser before, that'll give me something to consider for awhile...

lurk
MAXIM
User ID: 605304
United Kingdom
02/16/2009 01:33 PM
Report Abusive Post
Report Copyright Violation
Re: The Miracles of Laser Technology
This kind of laser technology was given to us by the reptilians. Firstly the ancient egyptians had it they used it to cut the pyramids and toms. It was a closely guarded secret. It passed trough generations of people to us.

News








Proud Member Of The Angry Mob