Patents by Inventor Stefan Nolte

Stefan Nolte 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).

  • Publication number: 20200412076
    Abstract: The invention relates to a device for generating a sequence of laser pulses consisting of pulse bursts. The object of the invention is to provide a possibility of generating laser pulses for material processing in the burst mode at a high quality based on the principle of beam combination.
    Type: Application
    Filed: September 4, 2018
    Publication date: December 31, 2020
    Applicants: Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Friedrich-Schiller-Universität Jena
    Inventors: Klaus Bergner, Stefan Nolte, Martin Gebhardt
  • Publication number: 20200398374
    Abstract: The invention concerns a method and an apparatus for processing an object (1) by means of interfering laser beams. It is the task of the invention to provide for an improved compensation of the aberrations accumulated over the beam path in such processes/apparatuses, since these are a substantial disturbing factor with respect to the precision in structuring the material. Furthermore, the influence of the period course, i.e. the spatial modulation of the period of the modification produced in the material of the object (1), shall be improved. The invention proposes that laser radiation is generated as a collimated laser beam (3). The intensity distribution and/or the phase progression is influenced over the cross-section of the laser beam (3) to correct aberrations. The laser beam (3) is divided into two partial beams (6, 7). Finally, the partial beams (6, 7) are deflected and focused so that the partial beams (6, 7) overlap in a processing zone (10) in the material of the object (1).
    Type: Application
    Filed: March 7, 2019
    Publication date: December 24, 2020
    Applicants: Fraunhofer-Gesellschaft zur Förderung der Angewandten Forschung E.V., Friedrich-Schiller-Universität Jena
    Inventors: Malte Per SIEMS, Stefan NOLTE, Daniel RICHTER, Ria KRÄMER, Thorsten Albert GOEBEL
  • Publication number: 20200333611
    Abstract: The invention relates to an arrangement for producing a Bessel beam (5), comprising a beam-forming element (2), which transforms a beam (1) incident as a plane electromagnetic wave into a Bessel beam (5). According to the invention, the beam-forming element (2) comprises at least one annular lens (3, 3?) and a Fourier optical unit, e.g. in the form of a Fourier lens (4).
    Type: Application
    Filed: June 22, 2017
    Publication date: October 22, 2020
    Applicants: Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Friedrich-Schiller-Universität Jena
    Inventors: Ralf Steinkopf, Stefan Nolte, Christian Vetter, Alexander Szameit, Herbert Gross, Marco Ornigotti
  • Publication number: 20200206841
    Abstract: The invention relates to a method for machining a transparent workpiece (4) by generating non-linear absorption of laser radiation in a laser beam focus located in a volume of the workpiece (4). The object of the invention is that of providing a method of improved precision and quality, and a corresponding device, for laser machining of workpieces. In particular, it is also intended for it to be possible for workpieces made of composite materials or of other special materials, such as filter glass, to be machined at an improved level of quality. For this purpose, the method according to the invention comprises the following steps: spectroscopic measurement of the linear absorption of the laser radiation in the workpiece (4), selecting a working wavelength at which the linear absorption is low, and machining the workpiece (4) by means of application of laser radiation at the working wavelength. The invention furthermore relates to a corresponding device for machining a transparent workpiece (4).
    Type: Application
    Filed: September 3, 2018
    Publication date: July 2, 2020
    Applicants: Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., Friedrich-Schiller-Universität Jena
    Inventors: Klaus Bergner, Stefan Nolte
  • 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: 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
  • Patent number: 8891917
    Abstract: The invention relates to a transverse mode filter in an optical waveguide (3). The aim of the invention is to produce a transverse mode filter that permits a monolithic construction of a laser in a multi-mode waveguide. To achieve this, according to the invention the filter comprises a Fabry-Perot cavity integrated into the optical waveguide (3) and comprising two reflective elements (5) situated at a distance from one another. In addition, the waveguide (3) is modified in the region of the Fabry-Perot cavity and/or in the region of the reflective elements (5) in relation to the remaining regions of the waveguide with respect to the effective refractive index of at least one mode of the waveguide.
    Type: Grant
    Filed: September 15, 2010
    Date of Patent: November 18, 2014
    Assignees: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Friedrich-Schiller-Universitaet Jena
    Inventors: Jens Ulrich Thomas, Christian Voigtlaender, Stefan Nolte, César Jáuregui Misas, Fabian Stutzki, Jens Limpert, Andreas Tuennermann
  • Patent number: 8778121
    Abstract: The present invention relates to a method for laser-assisted bonding of substrates, in which these are connected together firstly frictionally by pressing together and subsequently strengthening of the connection between the substrates is effected by activation in regions which is induced by laser irradiation. The invention likewise relates to substrates produced accordingly.
    Type: Grant
    Filed: February 21, 2008
    Date of Patent: July 15, 2014
    Assignees: Fraunhofer-Gesellschaft zur der Andewandten, Friedrich-Schiller-Universtaet Jena
    Inventors: Andreas Tuennermann, Ramona Eberhardt, Gerhard Kalkowski, Stefan Nolte
  • Publication number: 20120237162
    Abstract: The invention relates to a transverse mode filter in an optical waveguide (3). The aim of the invention is to produce a transverse mode filter that permits a monolithic construction of a laser in a multi-mode waveguide. To achieve this, according to the invention the filter comprises a Fabry-Perot cavity integrated into the optical waveguide (3) and comprising two reflective elements (5) situated at a distance from one another. In addition, the waveguide (3) is modified in the region of the Fabry-Perot cavity and/or in the region of the reflective elements (5) in relation to the remaining regions of the waveguide with respect to the effective refractive index of at least one mode of the waveguide.
    Type: Application
    Filed: September 15, 2010
    Publication date: September 20, 2012
    Applicants: FRAUNHOFER-GESELLSCHAFT ZUR FOERDERUNG DER ANGEWAN, FRIEDRICH-SCHILLER-UNIVERSITAET JENA
    Inventors: Jens Ulrich Thomas, Christian Voigtlaender, Stefan Nolte, César Jáuregui Misas, Fabian Stutzki, Jens Limpert, Andreas Tuennermann
  • Publication number: 20100304151
    Abstract: The present invention relates to a method for laser-assisted bonding of substrates, in which these are connected together firstly frictionally by pressing together and subsequently strengthening of the connection between the substrates is effected by activation in regions which is induced by laser irradiation. The invention likewise relates to substrates produced accordingly.
    Type: Application
    Filed: February 21, 2008
    Publication date: December 2, 2010
    Applicant: Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V.
    Inventors: Andreas Tuennermann, Ramona Eberhardt, Gerhard Kalkowski, Stefan Nolte