Patents by Inventor Ralf Krueger

Ralf Krueger 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).

  • PHASE SHIFT METHOD AND APPARATUS FOR IMPLEMENTING PHASE-CONTRAST OR MODULATION-CONTRAST OBSERVATION ON MICROSCOPES
    Publication number: 20040120029
    Abstract: The invention concerns an apparatus for implementing phase-contrast or modulation-contrast observation on microscopes with the aid of a modulator (7) arranged in each pupil plane in the observation beam path and containing at least one layer modifying the phase or amplitude, and of a stop (3) arranged in the illumination beam path. For stepless adaptation of the phase shift, the modulator (7) is mounted tiltably. The invention further concerns a method for implementing a defined phase shift.
    Type: Application
    Filed: October 2, 2003
    Publication date: June 24, 2004
    Inventor: Ralf Krueger
  • Polarizing interference microscope
    Publication number: 20040070826
    Abstract: In a polarizing interference microscope includes a light source, a polarizer, and an analyzer. An objective prism is arranged between the polarizer and analyzer. A birefringent compensation element is furthermore arranged in the immediate vicinity of the objective prism. A liquid crystal matrix element can be provided as the birefringent compensation element.
    Type: Application
    Filed: October 9, 2003
    Publication date: April 15, 2004
    Applicant: Leica Microsystems Wetzlar GmbH
    Inventor: Ralf Krueger
  • Method for the production of partially fluorinated fluoropolymers
    Patent number: 6346587
    Abstract: The present invention relates to a process for the production of partially fluorinated fluoropolymers, in accordance with which fluoromonomers are free-radically polymerized in the presence of polyfluoropropanes or polyfluorobutanes of the formulae CF3—CH2—CF2H, CF3—CHF—CF2—H, CF3—CH2—CF3, CHF2—CF2—CH2F, CF3—CH2—CF2—CH3 AND CF3—CHF—CF2—CH3 and optionally a chain-transfer agent.
    Type: Grant
    Filed: September 18, 2000
    Date of Patent: February 12, 2002
    Assignee: Bayer Aktiengesellschaft
    Inventors: Ralf Krüger, Gerhard Heilig, Claus Dieter Sommerfeld
  • Process for the preparation of low-viscosity fluorinated rubbers
    Patent number: 6211314
    Abstract: The present invention therefore provides a vulcanizable mixture comprising a low-viscosity fluorinated rubbers, in which at least one fluorine monomer is polymerized by free radicals in the presence of one or more compounds of the formula (I) or (II) wherein R1 represents a fluorine atom or a perfluoroalkyl radical having 1 to 4 carbon atoms and R2 represents a perfluoroalkyl radical having 1 to 4 carbon atoms and n=4 or 5, and, optionally, a molecular weight regulator.
    Type: Grant
    Filed: June 4, 1999
    Date of Patent: April 3, 2001
    Assignee: Bayer Aktiengesellschaft
    Inventors: Ralf Krüger, Wilhelm-Franz Biener