Patents by Inventor Walburga Kern

Walburga Kern 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).

  • Photoelectric position measuring device
    Patent number: 6445456
    Abstract: In a position measuring device, a scale is embodied as a phase grating on which several partial beams impinge and are diffracted and caused to interfere with each other in the scanning unit. The entry angle (&agr;) of the partial beams corresponds to the Littrow angle, so that the diffracted partial beams of ±1st diffraction order are diffracted at the same angle &bgr;=&agr;. The diffraction efficiency of the scale is particularly great if the flanks of the bars of the scales are at an angle of approximately 70° with respect to the measuring direction, i.e., if the bars and gaps are embodied to be trapezoidal in cross section.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: September 3, 2002
    Assignee: Dr. Johannas Heidenhain GmbH
    Inventors: Peter Speckbacher, Michael Allgäuer, Georg Flatscher, Anton Sailer, Walburga Kern
  • PHOTOELECTRIC POSITION MEASURING DEVICE
    Publication number: 20010046055
    Abstract: In a position measuring device, a scale is embodied as a phase grating on which several partial beams impinge and are diffracted and caused to interfere with each other in the scanning unit. The entry angle (&agr;) of the partial beams corresponds to the Littrow angle, so that the diffracted partial beams of ±1st diffraction order are diffracted at the same angle &bgr;=&agr;. The diffraction efficiency of the scale is particularly great if the flanks of the bars of the scales are at an angle of approximately 70° with respect to the measuring direction, i.e., if the bars and gaps are embodied to be trapezoidal in cross section.
    Type: Application
    Filed: December 16, 1997
    Publication date: November 29, 2001
    Inventors: PETER SPECKBACHER, MICHAEL ALLGAUER, GEORG FLATSCHER, ANTON SAILER, WALBURGA KERN