The Fraunhofer Institute for Laser Technology (ILT) unveiled the world’s most powerful ultra-short-pulse laser during Laser World of Photonics 2009 here this week. The femtosecond laser has an average output of more than 400 W and holds the world record for average output among lasers with pulse durations of less than one picosecond. The Fraunhofer researchers achieved the breakthrough by reinterpreting the InnoSlab technology that’s been under development at the institute for more than 10 years. The technology already forms the basis for many nano- and picosecond lasers systems presently in industrial use. The new laser comprises a single-pass amplifier with four mirrors and one laser crystal all of which make for an optomechanically and thermally robust and compact design. The development, the researchers say, could make it eventually possible to reach pulse energy below one mJ – significant in materials processing – without the need for complex chirped pulse application. Theoretical and experimental findings indicate that the practical limits of the ultra-short-pulse laser have not yet been reached. The Fraunhofer Institute ILT is already working on scaling the fs-laser to outputs greater than 1000 W. Diane M. Laurin Group Publisher