Fiber Lasers

Our Service

Fraunhofer ILT develops fiber lasers and amplifiers with adapted properties for pulsed and cw operation. Of paramount importance is the control of special properties – for example, polarization, bandwidth or beam quality. By using different conceptual designs for pulse generation, from gain switching to mode coupling, the institute has developed systems that generate pulse duration ranges from a few 10 picoseconds to milliseconds. With commercial and self-developed tools, it can simulate oscillators and linear amplifiers spectrally and temporally resolved.

Focal points of research and development are pulsed linear amplifiers, Q-switched and cw-fiber lasers with high output power and laser-written fiber gratings. Thanks to the appropriate assembly and connection technology, the institute can build laser systems with low attenuation and high performance stability. The high level of integration results in robust and adjustment-free beam sources. Currently, systems are based on active fibers with large cores in the range of 50 μm to 100 μm for pulsed operation with pulse durations of a few tens of nanoseconds and narrowband amplifiers for cw operation with line widths of less than 1 kHz.

Fraunhofer ILT offers its customers feasibility studies on individual tasks, the development of fiber lasers with adapted radiation properties, the integration, further development or simulation of fiber laser systems as well as consulting during project planning.

Komponentenhalter für die Durchführung von Vibrationstests.
© Fraunhofer ILT, Aachen.
Komponentenhalter für die Durchführung von Vibrationstests.
Q-switched high-power fiber laser for pulse durations in the ns range.
© Fraunhofer ILT, Aachen, Germany.
Q-switched high-power fiber laser for pulse durations in the ns range.
Saturable absorber for the generation of ps pulses.
© Fraunhofer ILT, Aachen, Germany.
Saturable absorber for the generation of ps pulses.

High Power cw-Lasers with Fundamental Mode Beam Quality

  • Free space resonators
  • Fiber-Bragg gratings
  • All-fiber lasers
  • Polarized lasers
  • Fiber laser resonators and amplifiers
  • Design and simulation

Pulsed Fiber Lasers and Amplifiers

  • Fiber amplifiers for pulsed laser diodes
  • Single- and multi-stage amplifiers
  • Gain-switched fiber lasers
  • PD from ps to µs
  • PRF from kHz to MHz

Efficient, High Brilliant Pumping Technology

  • Concentrated and allocated pumping
  • Multimode fused combiners
  • Single emitters, multi-single emitters, multi emitters

Fiber Preparation and Assembly, Fiber Laser Components

  • Cleaving, splicing, recoating
  • Fiber tapers
  • Mode strippers
  • Isolators
  • Detailed simulation 3D laser structuring for preforms and components

Brochures and Flyers

Our brochures and flyers offer a quick view onto the service portfolio “Fiber Lasers“. Find more detailed information in the “project results“ tab.


Brochure “Fiber Lasers“


Laser technology can solve demanding tasks in many different industries. Whether as a tool in automotive production, as measuring equipment in the environmental sector, as a diagnostic or therapeutic instrument in medical technology or as a communication medium in space technology, the laser provides multiple uses with high productivity and high efficiency.

Read up about the innovations of the Fraunhofer ILT in a few selected industries and convince yourself!


Neumann, A., Giesberts, M., Witte, U., Fitzau, O., Hoffmann, H.-D.:
Analytical model for diode-to-fiber coupling and beam propagation in weakly guiding fibers.
2017 IEEE High Power Diode Lasers and Systems Conference (HPD), 11 Oct - 12 Oct 2017, Coventry, UK.
Proc. IEEE High Power Diode Lasers & Systems, 35-36 (2017)

Fitzau, O.:
Polarized fiber lasers and amplifiers
Springer Series in Optical Sciences. Vol. 189, 251-263 (2015)

Mingareev, I., Gehlich, N., Bonhoff, T., Abdulfattah, A., Sincore, A. M., Kadwani, P., Shah, L., Richardson, M.:
Principles and applications of trans-wafer processing using a 2-µm thulium fiber laser
Int. J. Adv. Manuf. Technol. (Online first) (12 S.) (2015)

Becker, M., Werner, M., Fitzau, O., Esser, D., Kobelke, J.: Lorenz, A., Schwuchow, A., Rothhardt, M., Schuster, K., Hoffmann, D., Bartelt, H.:
Laser-drilled free-form silica fiber preforms for microstructured optical fibers
Opt. Fiber Technol. 19 (5), 482-485 (2013)

Becker, M., Werner, M., Fitzau, O., Esser, D., Kobelke, J., Schuster, K., Lorenz, A., Schwuchow, A., Rothhardt, M., Hoffmann, D., Bartelt, H.:
Laser processed preforms for microstructured optical fibers
Proc. SPIE 8785, 8785C9 (8 S.) (2013)

Katzy, V., Giesberts, M., Fitzau, O., Hoffmann, D.,:
Single mode all-fiber pulse-pumped Raman amplifier for picosecond pulses
Advanced Solid-State Photonics (ASSP), San Diego, California, Jan. 29th - Feb. 1st, 3 S., 2012

Fitzau, O., Geiger, J., Hoffmann, H.D.:
Experimental and theoretical studies on kW class polarized fiber lasers for cw operation
Proc. SPIE 7195, 719509 (9 S.), 2009

Giesberts, M.; Geiger, J., Traub, M., Hoffmann, H.-D.:
Novel design of a gain-switched diode-pumped fiber laser
Proc. SPIE 7195, 71952P (9 S.), 2009

Geiger, J., Fitzau, O., Zintzen, B., Hoffmann, D.:
Single-mode, highly polarized Y1456b-doped fiber laser with 850 W output power
ASSP 2008, Nara, Japan, Jan 27-30,(3 S.), 2008

Zintzen, B., Emmerich, A., Geiger, J., Hoffmann, D., Loosen, P.:
Effective cooling for high-power fiber lasers
Proc. of the 4th Int. WLT-Conf. on Lasers in Manufacturing , Munich, June 2007
(5 S.), 2007

Zintzen, B., Langer, T., Geiger, J., Hoffmann, D., Loosen, P.:
Heat transport in solid and air-clad fibers for high-power fiber lasers
Opt. Expr. 15, 16787-16793, (6 S.) 2007


Our services cover a wide range of topics. Related topics to fiber lasers and further research and development focuses can be found under the following links.