Brilliant high power laser bars for industrial applications

H. König^a, G. Grönninger^a, P. Brick^a, M. Reufer^a, F. Bugge^b, G. Erbert^b, M. Stoiber^c, J. Biesenbach^c, D. Lorenzen^d, P. Hennig^d, U. Strauß^a

^a OSRAM Opto Semiconductors GmbH, Leibnizstrasse 4, 93055 Regensburg, Germany
^b Ferdinand-Braun-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, D-12489 Berlin, Germany
^c DILAS Diodenlaser GmbH, Galileo-Galilei-Strasse 10, 55129 Mainz, Germany
^d Jenoptik Laserdiode GmbH, Göschwitzer-Strasse 29, 07745 Jena, Germany

Published in:
Proc. of SPIE Vol. 6876 687616-6.
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Abstract:
High power semiconductor lasers are commonly used as efficient pump sources for solid state lasers or multiplexing applications. Common wavelengths are 808nm e.g. for pumping of Nd:YAG and 9xx nm for pumping of disk or fiber lasers. Together with these wavelengths 880nm can be used as 3rd or 4th wavelength for multiplexing in direct material processing lasers. These industrial lasers are typically operating with some kW laser output power. For scaling to higher powers up to several kW, management of waste energy and power supply is gaining more and more importance. High efficient and reliable diode sources are vital to build systems with very good overall performance. The German framework project "BRILASI" had the target to develop basic technologies of next generation brilliant high power diode lasers for industrial applications.
In this paper we present laser bars which combine industrial standards with highest efficiencies at 808, 880, 940 and 980nm and power range above 100W/bar. Room temperature efficiencies of 70% were demonstrated at wavelengths above 900nm and power levels of 130W. For 808nm, we reached efficiencies up to 62% at 20°C. For high temperature operation, we will show laser structures of 808nm optimized for 50°C.

Keywords:
High power diode laser, high efficiency, high temperature operation

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