Post on 03-Feb-2021
FIBER LASERS
F R A U N H O F E R I N S T I T U T E F O R L A S E R T E C H N O L O G Y I LT
DQS certified by
DIN EN ISO 9001
Reg.-No.: DE-69572-01
Fraunhofer-Institut
für Lasertechnik ILT
Steinbachstraße 15
52074 Aachen, Germany
Telephone +49 241 8906-0
Fax +49 241 8906-121
info@ilt.fraunhofer.de
www.ilt.fraunhofer.de
Fraunhofer Institute for Laser Technology ILT
The Fraunhofer Institute for Laser Technology ILT is worldwide
one of the most important development and contract research
institutes of its specific field. The activities cover a wide range
of areas such as the development of new laser beam sources
and components, precise laser based metrology, testing
technology and industrial laser processes. This includes laser
cutting, caving, drilling, welding and soldering as well as
surface treatment, micro processing and rapid manufacturing.
Furthermore, the Fraunhofer ILT is engaged in laser plant
technology, process control, modeling as well as in the
entire system technology. We offer feasibility studies,
process qualification and laser integration in customer
specific manufacturing lines. The Fraunhofer ILT is part
of the Fraunhofer-Gesellschaft.
Subject to alterations in specifications and other technical information. 06/2019.
In cooperation with our customers, we design and
conceptualize customized beam sources for a wide variety
of applications:
• Linearly polarized single-mode fiber lasers
with output powers over 1 kW
• Single-mode fiber lasers with pulse durations in the pico
to microsecond range and peak power of 100 kW
• Q-switched, short-pulsed multimode fiber lasers
with peak powers above 250 kW
Such lasers can be applied, for example, in the industrial
structuring of surfaces with pulsed radiation, the preparation
of adhesive surfaces of composite components or cutting
and welding.
Highly stable fiber amplifiers for narrow band signals
Together with the European Space Agency ESA, Fraunhofer ILT
is developing narrow-band and power-stable single-mode fiber
amplifiers for future use in space applications, such as linearly
polarized fiber amplifiers with an output power of up to 5 W
and a line width below 10 kHz. The fiber amplifiers will be
used to measure the static gravitational field or gravitational
waves and in inter-satellite communication.
In order to investigate their suitability for space, Fraunhofer ILT
will expose the lasers to various stresses such as shock, vibration,
vacuum or cosmic radiation in a test campaign.
Simulation of optical components and fiber lasers
Various software tools are available at Fraunhofer ILT for the
development and design of new beam sources. These tools
are used to model both the thermo-mechanical properties
using finite element methods (FEM) and the spectral and tem-
poral properties of differently doped fiber lasers. In addition,
modal properties can be simulated for propagation in any fiber
geometry and mode coupling, e. g. in fiber Bragg gratings.
Fiber laser components, assembly
and joining technology
The fiber laser design places the highest demands on the
quality of the components. For this reason, Fraunhofer ILT
qualifies fiber-integrated and fiber-coupled components in
extensive tests for their respective applications. In many cases,
commercial components are not available due to the special
requirements and, therefore, have to be developed
at Fraunhofer ILT.
Examples for adapted fiber laser components
• Fiber Bragg gratings for multimode fibers
• Isolators and Pockels cells for use in space
and that are free of organic materials
• Soldered Pockels cells for use in high-power fiber lasers
• Isolators for use in high-power fiber lasers with powers
up into the kW range
• Pump and signal light couplers for adapted fiber geometries
• Splice connections of special geometries for use
in high-power fiber lasers
Contact
Dipl.-Phys. Oliver Fitzau
Telephone +49 241 8906-442
oliver.fitzau@ilt.fraunhofer.de
Dipl.-Ing. Hans-Dieter Hoffmann
Telephone +49 241 8906-206
hansdieter.hoffmann@ilt.fraunhofer.de
FIBER LASERS
The Fraunhofer Institute for Laser Technology ILT develops adapted, fiber-based beam sources for pulsed
or continuous wave operation and offers extensive know-how in the fields of highly stable fiber lasers,
high-power fiber lasers, simulation, assembly and joining technology as well as laser components. The
institute mainly focuses on solutions for industrial applications.
Fiber lasers combine highest beam quality and efficiency
in both continuous and pulsed operation. Since such lasers
can be designed monolithically and, therefore, very robustly
without free-space components, they have established them-
selves in industrial applications alongside gas and solid-state
lasers and have already partially replaced them. As their output
parameters such as power, wavelength or pulse shape are so
flexible, fiber lasers can be used for a wide range of applications.
In material processing, they can be used, for example, for
ablation and welding; in metrology, for interferometry and
also in medical technology applications.
High-power fiber lasers for industrial applications
In various R&D projects, Fraunhofer ILT scientists are creating
lasers with output powers in the kW range. Using fiber Bragg
gratings and pump light couplers, they can develop fully
fiber-integrated and thus particularly robust fiber lasers as
resonators or amplifiers. The output signal can be unpolarized
or linearly polarized, depending on the requirements.
Title: Q-switched high-power fiber laser.
1 Adapter for vibration tests on fiber components.
2 Highly stable fiber laser for gravitational measurements.
3 Active fiber in laser base plate.
4 Soldered Pockels cell as a Q-switch.
5 Narrow-band fiber laser for the investigation
of stimulated Brillouin scattering (SBS).
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