MUNICH, Feb. 21, 2013 — Laser World of Photonics 2013, to be held May 13-16 at the Messe München trade fair center, will cover new applications and trends related to ultrashort-pulse lasers.
Since the invention of the laser, its capabilities have fascinated users. It is extremely precise, uses extremely strong bundled energy, and is ideally suited for the extremely delicate tasks it performs. But lasers have one significant problem: their heat can damage or destroy materials and tissue, limiting their potential applications. The ultrashort-pulse laser, on the other hand, sends pulses of a few picoseconds or less into a material, cutting into or removing material before enough heat is generated to cause damage.
“The products on the market — at least those in the picosecond-laser range — are now suitable for industrial use and are being used in three-shift manufacturing,” said Christof Siebert, senior manager for microprocessing applications at Trumpf Laser- und Systemtechnik. Siebert will chair an application panel May 13 titled, “Latest Applications for Short-Pulse Laser Systems.”
The continued development of ultrashort-pulse lasers is an important aspect of the exhibition “Lasers and Laser Systems for Production Engineering” and a topic of discussion at the “Lasers in Manufacturing 2013” conference, which is part of the World of Photonics Congress at the International Congress Center München.
“The current trend is toward increasing average power as a way to optimize productivity and efficiency,” Siebert said. “The second is toward lasers that are suitable for industrial use with increasingly shorter pulse durations in order to expand the range of materials in cold processing to include more sensitive materials than in the past.”
For Dr. Arnold Gillner, head of Fraunhofer Institute for Laser Technology’s Department for Material Removal and Joining, the trend is toward higher average power in the 500-W range.
“At the Fraunhofer ILT, a prototype of a 1-kW femtosecond laser has already been demonstrated," said Gillner, who will lead the panel on ultrashort-pulse lasers with Siebert. “For the scientists, the key question is how to apply the higher average power of [ultrashort-pulse] lasers to the workpiece and achieve high ablation quality.”
At the fair, Fraunhofer ILT will introduce two approaches to doing so: an ultra-fast scanning system with beam-deflection speeds greater than 300 m/s, and a multiple-beam optics system to parallelize processing by more than two orders of magnitude.
Aside from technical feasibility, cost plays a significant role in these recent developments. One objective of the Jenoptik experts is, for example, to use higher power and the resulting increased productivity to offset the costs of investing in femtosecond lasers. The company has increased the pulse-repetition rate of its D2.fs femtosecond disk laser to more than 500 kHz and improved its output power by 25 percent. Jenoptik is also using a new series of lenses to round out its range of all-quartz lenses for high laser power.
Ultrashort-pulse lasers can be used in a variety of application fields, including precision processing of transparent materials and extremely hard, brittle materials, said Dr. Gyu C. Cho, IMRA executive vice president. New applications are also possible in terms of composite materials, Cho said.
IMRA manufactures femtosecond lasers for a variety of applications with an average power of up to 20 W and a pulse energy of 50 microjoules. According to Dr. Cho, the first industries that will profit from ultrashort-pulse lasers include display manufacturing as well as the semiconductor and microelectronics industry.
Such lasers could also be used differently on glass or brittle materials — on thinner, harder glass touch screens for smartphones, for example.
“Picosecond lasers like the TruMicro Series 5000 are ideal for cutting the glass plates,” Siebert said. “This technique avoids microcracks that appear when diamond saws or continuous- or long-pulse lasers are used.”
The technology also offers advantages in medicine and medical technology. The most important trend in medicine "is the use of ultrashort-pulse lasers in laser refractive cataract surgery,” said Dr. Matthias Schulze, marketing director at Coherent. This has been the most rapidly growing application for lasers in medicine in the last one to two years. The technology permits "even better vision when replacing the intraocular lens (IOL) in cataract surgery," Schulze said. For example, it makes it possible to better prepare the eye for the use of premium IOLs by using precision cuts to correct astigmatism.
"Compact lasers will make it possible to use smaller treatment stations, and higher pulse rates will make operation times even shorter," Schulze said.
“At present, the only market applications that are worth mentioning are in the picosecond range," said Dr. Josef Gochermann, managing director of LOTSE, a consulting firm that conducted a market study for the Rostock Welding and Research Institute at the Mikrolas Innovation Forum. "Potential future users of ultrashort-pulse technologies still know too little about the possible uses of this technology and the benefits that they can expect for their specific applications."
For more information, visit: www.world-of-photonics.net/en/laser/start