Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > World record: 400 W femtosecond laser for ultra-precise materials processing

World record: 400 W femtosecond laser developed by the Fraunhofer ILT for ultra-precise materials processing
Picture source: Fraunhofer Institute for Laser Technology ILT, Aachen
World record: 400 W femtosecond laser developed by the Fraunhofer ILT for ultra-precise materials processing Picture source: Fraunhofer Institute for Laser Technology ILT, Aachen

Abstract:
Femtosecond lasers (fs-lasers) are the key to ultra-precision processing. Whether in medicine, electronics, aerospace or solar technology, thin coatings can be removed, fiber-reinforced plastics drilled and ceramic components' surfaces structured using fs-lasers. Wider use of fs-lasers, however, is hampered by the average output which is currently limited to below 100 W on commercial systems. At the LASER World of Photonics 2009 in Munich the Fraunhofer Institute for Laser Technology ILT will show for the first time the currently most powerful ultra-short-pulse laser module with an output of over 400 watts and pulse durations of less than 1 ps.

World record: 400 W femtosecond laser for ultra-precise materials processing

Munich, Germany | Posted on May 12th, 2009

Femtosecond (fs) lasers, i.e. lasers with pulse durations of less than one picosecond, have experienced a stormy development on the scientific front since their beginnings 35 years ago. The interaction of fs-laser radiation with material is characterized by the fact that the pulse duration is shorter than most interaction times between atoms or atoms and electrons. Thus, when material is processed, heat conduction, melting, evaporation and plasma formation only take place after the impact of the laser radiation. In contrast to longer nanosecond pulses or continuous wave (cw) lasers, no direct interaction of light and diffusing material takes place, which facilitates high-precision material removal. With fs-lasers it is therefore possible to achieve processing results which cannot be matched by any other method.

A major obstacle to the widespread use of present fs-lasers, however, is their average output power. Whereas cw-fiber and disk lasers nowadays reach an average output of a kilo-watt and more with diffraction-limited beam quality, the output power of fs-lasers is typically in the range of a single watt. 50-watt lasers are regarded as the high-end range for commercial lasers. Owing to their complex design, the price for such systems is a few hundred thousand euros. The high price and output-limited processing speed are therefore restricting the present potential of fs-lasers. Up to now they have not been widely embraced in production.

At the LASER World of Photonics 2009 the Fraunhofer ILT is unveiling the currently most powerful ultra-short-pulse laser module. This was developed in part under the LASERTRON (FKZ 13N8720) joint project with funding from the German Ministry of Education and Research (BMBF) under the FEMTONIK program. With an average output of more than 400 watts, it holds the world record for average output among lasers with pulse durations of less than one picosecond.

This was made possible by reinterpreting the InnoSlab technology which has been under development at the Fraun-hofer Institute for Laser Technology (ILT) for more than 10 years. This technology already forms the basis for numerous nano- and picosecond laser systems in industrial use. The extremely simple construction of the single-pass amplifier with four mirrors and one laser crystal permits an opto-mechanically and thermally robust and compact design.

In addition, a reduction and adaptation of the intensities arising is concept-inherent and makes it possible to reach pulse energies below one millijoule - which are relevant in particular for micro materials processing - without the need for complex chirped pulse amplification (CPA). This represents a further breakthrough for the simplification of fs-laser systems and the costs they entail, which is a key requirement for their widespread use in industrial practice.

The innovative laser from the Fraunhofer ILT is characterized by the fact that the oscillators with an output power of 1-2 watts can be amplified up to 400 watts by means of a single amplifier stage. At full output, a beam quality of M2<1.4 and an optical efficiency of 50% are attained. The almost diffraction-limited beam quality permits transformation into a round beam over the entire propagation range, which is frequently required for applications.

Further highlights include pulse durations below 700 fs and spectral bandwidths below 2 nm. The pulses are therefore distinctly shorter than on present ps-lasers and produce better results, for example in micro materials processing. Also, the bandwidth and wavelength unrestrictedly permit the use of the same optics as on typical ps and ns lasers. Special attachments for time compression (compressors), as frequently necessary on ultra-short-pulse lasers, are no longer required. The problems which can be caused by these attachments, such as pulse front / phase front tilt, therefore do not arise.

Given the bandwidth-limited spectrum and the high pulse peak output power, the laser radiation is very suitable for non-linear frequency conversion. Ongoing tasks include frequency doubling, compression of the pulse duration and production of high harmonics. Use in the scientific field will be made possible in future by increasing the pulse energy to the multi 10mJ range at several 100 watts of average output using additional CPA.

According to all the theoretical and experimental findings, the practical limits of the ultra-short-pulse laser have not yet been reached. The Fraunhofer ILT is therefore already working on scaling the innovative fs-laser to outputs of greater than 1000 watts. The results of the new technology will be presented to a broad specialist public at the joint Fraunhofer stand in Hall C2 at LASER 2009 in Munich from June 15 to 18, 2009.

####

For more information, please click here

Contacts:
Fraunhofer Institute for Laser Technology ILT
Steinbachstr. 15
D-52074 Aachen
Germany

Phone +49 241 8906-0
Fax +49 241 8906-121
email

Copyright © Fraunhofer

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

New flexible material can make any window 'smart' August 23rd, 2016

University of Puerto Rico and NASA back in the news XEI reports August 23rd, 2016

Nanoparticles that speed blood clotting may someday save lives August 23rd, 2016

Spider silk: Mother Nature's bio-superlens August 22nd, 2016

Announcements

New flexible material can make any window 'smart' August 23rd, 2016

University of Puerto Rico and NASA back in the news XEI reports August 23rd, 2016

Nanoparticles that speed blood clotting may someday save lives August 23rd, 2016

Researchers reduce expensive noble metals for fuel cell reactions August 22nd, 2016

Events/Classes

Nanoparticles that speed blood clotting may someday save lives August 23rd, 2016

Impressive List of Doctors, Scientists Coming to Vail for Scientific Summit: The Second Vail Scientific Summit Convenes the Greatest Minds in Regenerative Medicine and Science August 17th, 2016

Harris & Harris Group to Host a Shareholder Update Call, Including a Presentation by One of Its Precision Health and Medicine Portfolio Companies, Muses Labs, Inc., on August 23, 2016 August 16th, 2016

Pokhara, the second largest city of Nepal, to host its first ever International Meeting on Material Sciences and Engineering August 15th, 2016

Photonics/Optics/Lasers

Hexagonal boron nitride semiconductors enable cost-effective detection of neutron signals: Texas Tech University researchers demonstrate hexagonal boron nitride semiconductors as a cost-effective alternative for inspecting overseas cargo containers entering US ports August 17th, 2016

Prototype chip could help make quantum computing practical: Built-in optics could enable chips that use trapped ions as quantum bits August 9th, 2016

Scientists discover light could exist in a previously unknown form August 6th, 2016

Tiny high-performance solar cells turn power generation sideways August 5th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic