Fraunhofer-Gesellschaft

Publica

Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Fiber-coupled high brightness high power diode laser for solid-state laser pumping and material processing

 
: Ehlers, B.; Heinemann, S.; Doerfel, F.

:

Zediker, M.S. ; Society of Photo-Optical Instrumentation Engineers -SPIE-, Bellingham/Wash.:
High-power diode laser technology and applications : 27 - 28 January 2003, San Jose, California, USA
Bellingham/Wash.: SPIE, 2003 (SPIE Proceedings Series 4973)
ISBN: 0-8194-4773-0
pp.47-53
High-Power Diode Laser Technology and Applications <2003, San Jose/Calif.>
English
Conference Paper
Fraunhofer ILT ()

Abstract
Two applications emerge as drivers for higher brightness fiber-coupled diode lasers: advanced solid-state pumping schemes and materials processing. In contrast to the well-established side-pumping schemes of laser rods, advanced pumping schemes for today's solid-state lasers make use of the high brightness of the pump sources to increase the performance and efficiency of the solid-state laser. Materials processing applications such as metal welding and cutting are commonly served with solid-state lasers or CO2 lasers. Lately, the increased lifespan, reduced systems costs and increased brightness of fiber-coupled diode laser systems make them a new alternative. In this work, a diode laser system is described that yields 250 watts in a 600 micrometer spot with a numerical aperture 0.2 of the focused beam, corresponding to a F/# of 2.4. The system is based on a single 15 bar stack that operates in cw-mode. For brightness enhancement, it incorporates a measure to increase t he fill factor of the emitting aperture and polarization multiplexing. The brightness in the focus spot is 105W/cm2 with a F/# of 2.4 focusing optic and 3.105 W/cm2 with a high speed F/# of 1.4. To achieve the required symmetry for fiber coupling, the system incorporates a beam transformer that assimilates the beam quality along the two main axes of the beam profile. A monolithic design is chosen to reduce alignment tolerances and to increase ruggedness.

: http://publica.fraunhofer.de/documents/N-168995.html