Patents by Inventor Arkadi Rosenfeld

Arkadi Rosenfeld 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: 20110297653
    Abstract: An apparatus and a method for producing nanostructured surfaces are particularly suited for producing surfaces having very low roughness over large lateral extents. The method includes the following steps: providing an article having a surface to be structured; generating short-pulse laser radiation with laser pulses whose pulse durations lie in the subnanosecond range, preferably in the range of 100 fs to 300 fs, directing the short-pulse laser radiation onto the surface to be structured on the article, such that a fluence F of each individual pulse of the short-pulse laser radiation is less than a multishot threshold fluence Fth for a multishot laser ablation, but the fluence F is chosen to be high enough that defects can be produced by way of nonlinear interactions. Preferably, a fluence F in the range of 65% to 95% of the multishot threshold fluence Fth for a multishot laser ablation is used.
    Type: Application
    Filed: June 8, 2011
    Publication date: December 8, 2011
    Applicant: FORSCHUNGSVERBUND BERLIN E.V.
    Inventors: LUTZ EHRENTRAUT, ARKADI ROSENFELD, INGOLF HERTEL
  • Patent number: 7751668
    Abstract: The invention relates to a method for microstructuring an optical waveguide having a first cross-sectional region with a first refractive index, a second cross-sectional region with a second refractive index, and a boundary region in the transition from the first to the second cross-sectional region, in which the optical waveguide is exposed to laser radiation in the form of at least one ultra-short single pulse or a sequence of pulses with a defined energy input, whereby the radiant exposure takes place in such a manner that a modification of at least one optical property of the optical waveguide takes place at at least one defined portion of the boundary region.
    Type: Grant
    Filed: July 4, 2003
    Date of Patent: July 6, 2010
    Assignee: CeramOptec Industries, Inc.
    Inventors: David Ashkenasi, Arkadi Rosenfeld, Verena Knappe, Gerhard Müller
  • Publication number: 20080143021
    Abstract: The invention relates to a method for finely polishing/structuring thermosensitive dielectric materials, in particular materials exhibiting a low thermal expansion coefficient, by a laser beam consisting in directing an intensive ultrashort laser beam to a processable material surface, in adjusting the action time within a range from 10-13 s to 10-11 s and a laser pulse energy in such a way that it is less than an ablation threshold but sufficient for provoking a Coulomb explosion. The inventive method makes it possible to carry out a material removal within a nanometer range by means of laser ultrashort pulses ranging between picoseconds and subpicoseconds, wherein the material surface is finely polished during a pre-ablation process step (removal less than the ablation range) and the processable surface is low-heated (approximately up to 10° C., only) due to the extremely shot laser beam action time.
    Type: Application
    Filed: March 21, 2006
    Publication date: June 19, 2008
    Inventors: Lutz Ehrentraut, Ingolf Hertel, Arkadi Rosenfeld
  • Publication number: 20060147170
    Abstract: The invention relates to a method for microstructuring an optical waveguide having a first cross-sectional region with a first refractive index, a second cross-sectional region with a second refractive index, and a boundary region in the transition from the first to the second cross-sectional region, in which the optical waveguide is exposed to laser radiation in the form of at least one ultra-short single pulse or a sequence of pulses with a defined energy input, whereby the radiant exposure takes place in such a manner that a modification of at least one optical property of the optical waveguide takes place at at least one defined portion of the boundary region.
    Type: Application
    Filed: July 4, 2003
    Publication date: July 6, 2006
    Inventors: David Ashkenasi, Arkadi Rosenfeld, Verena Knappe, Gerhard Muller