Patents by Inventor Andreas Tuennermann

Andreas Tuennermann has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11043783
    Abstract: The invention relates to an optical arrangement having a division element which divides an input beam consisting of a sequence of temporally equidistant light pulses into two spatially separate partial beams, at least one optical element through which at least one of the partial beams propagates, and at least one combination element which spatially superimposes the partial beams in an output beam. It is the object of the present invention to show a method for increasing the pulse energy of light pulses which is improved in comparison with the prior art. The invention solves this problem by virtue of the fact that the combination element superimposes a number of the temporally successive light pulses in a single light pulse in the output beam. The invention also relates to a method for increasing the pulse energy of light pulses.
    Type: Grant
    Filed: December 20, 2016
    Date of Patent: June 22, 2021
    Assignees: Fraunhoer-Gesellschaft zur Förderung der angewandten Forschung e.V., Friedrich-Schiller-Universität Jena
    Inventors: Michael Müller, Marco Kienel, Arno Klenke, Jens Limpert, Andreas Tünnermann
  • Publication number: 20210091527
    Abstract: The invention relates to an apparatus for generating laser pulses. It is an object of the invention to provide a method for generating synchronized laser pulse trains at variable wavelengths (e.g., for coherent Raman spectroscopy/microscopy), wherein the switching time for switching between different wavelengths should be in the sub-?s range. For this purpose the apparatus according to the invention comprises a pump laser (1), which emits pulsed laser radiation at a specified wavelength, an FDML laser (3), which emits continuous wave laser radiation at a cyclically variable wavelength, and a nonlinear conversion medium (4), in which the pulsed laser radiation of the pump laser (1) and the continuous wave laser radiation of the FDML laser (3) are superposed.
    Type: Application
    Filed: July 12, 2018
    Publication date: March 25, 2021
    Applicants: Fraunhofer-Gesellschaft zur Förderung der Angewandten Forschung E.V., Friedrich-Schiller-Universitat Jena, Leibniz-lnstitut Für Photonische Technologien E.V.
    Inventors: Thomas GOTTSCHALL, Jens LIMPERT, Andreas TÜNNERMANN, Tobias MEYER, Jürgen POPP
  • Publication number: 20200153190
    Abstract: The invention relates to a method for stably transmitting laser radiation through an optical waveguide (3), wherein two or more modes of the laser radiation propagating in the optical waveguide (3) interfere and form a mode interference pattern in the optical waveguide, as a result of which a thermally induced refractive index grating is produced in the optical waveguide (3). It is an object of the invention to demonstrate an effective approach for stabilizing the output signal of the optical waveguide (3) in a fiber-based laser/amplifier combination at high output powers, i.e. for avoiding mode instability. The invention achieves this object by virtue of the fact that a relative spatial phase shift between the mode interference pattern and the thermally induced refractive index grating is set in the direction of propagation of the laser radiation.
    Type: Application
    Filed: July 17, 2018
    Publication date: May 14, 2020
    Applicants: Fraunhofer-Gesellschaft zur Förderung der Angewandten Forschung E.V., Friedrich-Schiller-Universität Jena
    Inventors: Christoph STIHLER, César JÁUREGUI MISAS, Jens LIMPERT, Andreas TÜNNERMANN
  • Patent number: 10490969
    Abstract: A method of propagating a laser signal through an optical waveguide and a waveguide laser system provide a novel way of stabilizing the beam emitted by a fiber laser system above the mode instability threshold wherein the beat length of two or more interfering transverse modes of the laser signal in the optical waveguide is modulated in time.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: November 26, 2019
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e. V., Friedrich-Schiller-Universitaet Jena
    Inventors: Christoph Stihler, César Jáuregui Misas, Jens Limpert, Hans-Juergen Otto, Andreas Tuennermann, Fabian Stutzki
  • Publication number: 20190013637
    Abstract: The invention relates to an optical arrangement having a division element which divides an input beam consisting of a sequence of temporally equidistant light pulses into two spatially separate partial beams, at least one optical element through which at least one of the partial beams propagates, and at least one combination element which spatially superimposes the partial beams in an output beam. It is the object of the present invention to show a method for increasing the pulse energy of light pulses which is improved in comparison with the prior art. The invention solves this problem by virtue of the fact that the combination element superimposes a number of the temporally successive light pulses in a single light pulse in the output beam. The invention also relates to a method for increasing the pulse energy of light pulses.
    Type: Application
    Filed: December 20, 2016
    Publication date: January 10, 2019
    Inventors: Michael MÜLLER, Marco KIENEL, Arno KLENKE, Jens LIMPERT, Andreas TÜNNERMANN
  • Publication number: 20180034234
    Abstract: The invention relates to an optical waveguide (3) as a laser medium or as a gain medium for high-power operation, wherein the optical waveguide (3) is an optical fiber, the light-guiding core of which, at least in sections, is doped with rare earth ions. It is an object of the invention to provide an optical waveguide as a laser or a gain medium, and a laser/amplifier combination realized therewith, in which the output signal of the laser or gain medium is better stabilized. The invention achieves this object by virtue of the maximum small signal gain of the optical waveguide (1) being up to 60 dB, preferably up to 50 dB, more preferably up to 40 dB, even more preferably up to 30 dB, on account of the concentration of the rare earth ions and/or the distribution thereof in the light-guiding core. Moreover, the invention relates to the use of such an optical waveguide as an amplifier fiber (3) in a laser/amplifier combination.
    Type: Application
    Filed: February 12, 2015
    Publication date: February 1, 2018
    Applicants: Fraunhofer-Gesellschaft Zur Förderung Der Angewandten Forschung E.V., Friedrich-Schiller-Universität
    Inventors: Hans Jürgen OTTO, César JAUREGUI MISAS, Jens LIMPERT, Andreas TÜNNERMANN
  • Publication number: 20180019566
    Abstract: A method of propagating a laser signal through an optical waveguide and a waveguide laser system provide a novel way of stabilizing the beam emitted by a fiber laser system above the mode instability threshold wherein the beat length of two or more interfering transverse modes of the laser signal in the optical waveguide is modulated in time.
    Type: Application
    Filed: July 14, 2017
    Publication date: January 18, 2018
    Applicants: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e. V., Friedrich-Schiller-Universitaet Jena
    Inventors: Christoph STIHLER, César JÁUREGUI MISAS, Jens LIMPERT, Hans-Juergen OTTO, Andreas TUENNERMANN, Fabian STUTZKI
  • Patent number: 9484709
    Abstract: The invention relates to an optical amplifier arrangement for amplifying ultra-short pulsed laser radiation comprising a mode-locked laser (1) and two or more optical amplifiers (3) arranged downstream of the laser (1) in the propagation direction of the laser radiation. Optical amplifier arrangements of this type are known in the prior art. Here the intention is to present an alternative to the known amplifier arrangements. The invention proposes arranging between the laser (1) and the optical amplifiers (3) at least one splitting element (2) which splits the pulsed laser radiation between a plurality of amplifier channels (4), wherein each amplifier channel (4) has at least one optical amplifier (3), and wherein at least one common combination element (5) is disposed downstream of the amplifier channels (4) and coherently superimposes the pulsed laser radiation amplified in the amplifier channels (4).
    Type: Grant
    Filed: August 29, 2011
    Date of Patent: November 1, 2016
    Assignees: FRAUNHOFER-GESELLSCHAFT ZUR FOERDERUNG DER ANGEWANDTEN FORSCHUNG E.V., FRIEDRICH-SCHILLER-UNIVERSITAET JENA
    Inventors: Arno Klenke, Enrico Seise, Jens Limpert, Andreas Tuennermann
  • Patent number: 9459403
    Abstract: The invention relates to an apparatus for generating azimuthally or radially polarized radiation by means of an optical waveguide (1), wherein the optical waveguide (1) has a structure which is suitable for conducting azimuthally or radially polarized modes (5, 7). The invention proposes that the azimuthally or radially polarized modes (5, 7) in the optical waveguide (1) have different effective refractive indices and, within the optical waveguide (1), a narrow-band grating (2) is arranged, in particular a fiber Bragg grating (2) which is designed such that the spectral distance between two azimuthally or radially polarized resonant modes (5, 7) is equal to or greater than the associated spectral bandwidth.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: October 4, 2016
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Friedrich-Schiller-Universitaet Jena
    Inventors: Andreas Tuennermann, Christoph Jocher, César Jauregui Misas, Jens Limpert
  • Patent number: 9448359
    Abstract: The invention relates to an optical fiber as an optical waveguide for the single-mode operation. The present invention proposes a fiber having a microstructure, by which the propagation of modes of a higher order are selectively suppressed in the optical waveguide. At the same time, the propagation of transversal modes of a higher order is dampened more strongly than the propagation of the fundamental modes of the optical waveguide.
    Type: Grant
    Filed: September 21, 2015
    Date of Patent: September 20, 2016
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Friedrich-Schiller-Universitaet Jena
    Inventors: Jens Limpert, Fabian Roeser, Tino Eidam, César Jáuregui Misas, Andreas Tuennermann
  • Patent number: 9360617
    Abstract: The invention relates to a mode filter for reducing higher-order modes, with an optical fiber (1), which has a core (2) and a cladding (3) surrounding the latter, wherein the cladding (3) and core (2) have refractive indices that differ from one another. In order to develop an alternative to the prior art, the mode filter according to the invention is designed in such a manner that the fiber (1) has, in a transition region (4) between core (2) and cladding (3), at least one local refractive index modification region (5) which is arranged in the radially outer region of the core (2) and extends into the region of the cladding (3).
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: June 7, 2016
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e. V., Fried-Schiller-Universitaet Jena
    Inventors: Christian Voigtlaender, Jens Ulrich Thomas, Robert Williams, Stefan Nolte, Andreas Tuennermann
  • Publication number: 20160025924
    Abstract: The invention relates to an optical fiber as an optical waveguide for the single-mode operation. The present invention proposes a fiber having a microstructure, by which the propagation of modes of a higher order are selectively suppressed in the optical waveguide. At the same time, the propagation of transversal modes of a higher order is dampened more strongly than the propagation of the fundamental modes of the optical waveguide.
    Type: Application
    Filed: September 21, 2015
    Publication date: January 28, 2016
    Applicants: FRAUNHOFER-GESELLSCHAFT ZUR FOERDERUNG DER ANGEWANDTEN FORSCHUNG E.V., FRIEDRICH-SCHILLER-UNIVERSITAET JENA
    Inventors: Jens LIMPERT, Fabian ROESER, Tino EIDAM, César JÁUREGUI MISAS, Andreas TUENNERMANN
  • Patent number: 9235106
    Abstract: The invention relates to a method and corresponding devices for reducing mode instability in an optical waveguide (1), a light signal becoming unstable in the optical waveguide (1) beyond an output power threshold and energy being transformed from a basic mode into higher order modes. The invention proposes a reduction in temperature variation (2) along the optical waveguide (1) and/or a reduction in changes in the optical waveguide (1) that are caused by spatial temperature variation as a result of mode interference.
    Type: Grant
    Filed: April 12, 2013
    Date of Patent: January 12, 2016
    Assignees: FRAUNHOFER-GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG e.V., FRIEDRICH-SCHILLER-UNIVERSITÄT JENA
    Inventors: César Jáuregui Misas, Hans-Jürgen Otto, Fabian Stutzki, Florian Jansen, Tino Eidam, Jens Limpert, Andreas Tünnermann
  • Patent number: 9170368
    Abstract: The invention relates to an optical fiber as an optical waveguide for the single-mode operation. The present invention proposes a fiber having a microstructure, by which the propagation of modes of a higher order are selectively suppressed in the optical waveguide. At the same time, the propagation of transversal modes of a higher order is dampened more strongly than the propagation of the fundamental modes of the optical waveguide.
    Type: Grant
    Filed: March 12, 2010
    Date of Patent: October 27, 2015
    Assignees: FRAUNHOFER-GESELLSCHAFT ZUR FOERDERUNG DER ANGEWANDTEN FORSCHUNG E.V., FRIEDRICH-SCHILLER-UNIVERSITAET JENA
    Inventors: Jens Limpert, Fabian Roeser, Tino Eidam, César Jáuregui Misas, Andreas Tuennermann
  • Patent number: 9065245
    Abstract: The invention relates to a double-sheath fiber having a core region (1) and a sheath region, the sheath region having an inner region (2) and an outer region (3), which comprises a refractive index that is lower with respect to that of the inner region (2) and the core region (1), wherein the outer region (3) surrounds the inner region (2). The invention proposes an internal structure (4) of the inner region (2) which effects a spatial overlap of modes of higher order with the core region (1), which is lower than the spatial overlap of a fundamental mode with the core region (1).
    Type: Grant
    Filed: November 22, 2011
    Date of Patent: June 23, 2015
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Friedrich-Schiller-Universitaet Jena
    Inventors: César Jauregui Misas, Fabian Stutzki, Jens Limpert, Florian Jansen, Andreas Tuennermann
  • Patent number: 9057928
    Abstract: The invention relates to an apparatus for generation of electromagnetic radiation, having a pump light source that emits an excitation radiation at a first wavelength, and having an optical waveguide that generates frequency-converted radiation at a second and a third wavelength, by means of degenerate wave mixing, from the excitation radiation of the pump light source.
    Type: Grant
    Filed: December 19, 2011
    Date of Patent: June 16, 2015
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Friedrich-Schiller-Universitaet Jena
    Inventors: César Jauregui Misas, Andreas Tuennermann, Jens Limpert, Dirk Nodop
  • Patent number: 8982453
    Abstract: The invention relates to a laser device (1) for amplifying and/or transporting electromagnetic radiation, comprising a radiation source (2) for generating the electromagnetic radiation and an amplifier (4) for amplifying or a medium for transporting the generated electromagnetic radiation. In order to make available a device (1) for amplifying or transporting electromagnetic radiation that provides a very easy to implement possibility for reducing the influence of non-linear effects, the electromagnetic radiation propagating in the amplifier (4) or medium is largely non-linearly polarized.
    Type: Grant
    Filed: July 9, 2010
    Date of Patent: March 17, 2015
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung E.V., Friedrich-Schiller-Universitaet Jena
    Inventors: Jens Limpert, Andreas Tuennermann, Damian Schimpf, Tino Eidam, Enrico Seise, Fabian Roeser
  • Publication number: 20150063767
    Abstract: The invention relates to a method and corresponding devices for reducing mode instability in an optical waveguide (1), a light signal becoming unstable in the optical waveguide (1) beyond an output power threshold and energy being transformed from a basic mode into higher order modes. The invention proposes a reduction in temperature variation (2) along the optical waveguide (1) and/or a reduction in changes in the optical waveguide (1) that are caused by spatial temperature variation as a result of mode interference.
    Type: Application
    Filed: April 12, 2013
    Publication date: March 5, 2015
    Applicants: FRAUNHOFER-GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG e.V., FRIEDRICH-SCHILLER-UNIVERSITÄT JENA
    Inventors: César Jáuregui Misas, Hans-Jürgen Otto, Fabian Stutzki, Florian Jansen, Tino Eidam, Jens Limpert, Andreas Tünnermann
  • Patent number: 8948219
    Abstract: The invention relates to a laser system with a passively Q-switched laser 1, a spectrally widening element 3, and a compression element 4. Laser systems of this kind are utilized for generating ultra-short laser pulses. Systems, mode-coupled solid-state lasers known from prior art allow for generating laser pulses in the sub-10 ps range only with complicated and alignment-sensitive free-beam arrangements. Therefore, it is the object of the present invention to create a laser system that generates pulse durations of less than 10 ps and which is simple and compact to produce at the same time. In order to achieve this object, the present invention proposes that the passively Q-switched laser 1 is provided with a longitudinally monomode output radiation which is spectrally widened by means of the spectrally widening element 3 by self-phase modulation and is temporally compressed by the compression element 4.
    Type: Grant
    Filed: April 13, 2011
    Date of Patent: February 3, 2015
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung E.V., Friedrich-Schiller-Universitaet Jena
    Inventors: Dirk Nodop, Alexander Steinmetz, Jens Limpert, Andreas Tuennermann
  • Publication number: 20140362878
    Abstract: The invention relates to a mode filter for reducing higher-order modes, with an optical fibre (1), which has a core (2) and a cladding (3) surrounding the latter, wherein the cladding (3) and core (2) have refractive indices that differ from one another. In order to develop an alternative to the prior art, the mode filter according to the invention is designed in such a manner that the fibre (1) has, in a transition region (4) between core (2) and cladding (3), at least one local refractive index modification region (5) which is arranged in the radially outer region of the core (2) and extends into the region of the cladding (3).
    Type: Application
    Filed: September 27, 2012
    Publication date: December 11, 2014
    Applicants: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Friedrich-Schiller-Universitaet Jena
    Inventors: Christian Voigtlaender, Jens Ulrich Thomas, Robert Williams, Stefan Nolte, Andreas Tuennermann