Patents by Inventor Johannes A. Pistorius

Johannes A. Pistorius 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).

  • Monocrystalline MnZn-ferroferrite material having a high content of Zn, and a magnetic head manufactured from said material
    Patent number: 5049454
    Abstract: Monocrystalline MnZn-ferroferrite material having a high Zn-content, and magnetic head comprising the said material.A monocrystalline MnZn-ferroferrite material for use in a magnetic head is described. The material corresponds to the formulaMn.sub.a Zn.sub.b Fe.sub.c.sup.II Fe.sub.2.sup.III O.sub.4,wherein0.25<a<0.48;0.50<b<0.60;0.02<c<0.15;a+b+c=1.The magnetostriction constants of this material are particularly small.
    Type: Grant
    Filed: June 20, 1989
    Date of Patent: September 17, 1991
    Assignee: U.S. Philips Corporation
    Inventors: Mark T. Johnson, Johannes F. M. Cillessen, Johannes A. Pistorius
  • Monocrystalline material having garnet structure
    Patent number: 4961919
    Abstract: A description is given of the composition and preparation of single phase crystals having a garnet structure and a lattice constant smaller than 11.9 .ANG.. The garnets correspond to the formula{Mn.sub.3-a-b Mg.sub.a M.sub.b }[Al.sub.2-c M'.sub.c ](Ge.sub.3-d-e Si.sub.d M".sub.e)O.sub.12 (I)wherein0.0.ltoreq.a.ltoreq.0.40.0.ltoreq.b.ltoreq.0.40.0.ltoreq.c.ltoreq.0.20.0.ltoreq.d.ltoreq.0.50.0.ltoreq.e.ltoreq.0.60.2.ltoreq.a+d.ltoreq.0.8.
    Type: Grant
    Filed: January 6, 1989
    Date of Patent: October 9, 1990
    Assignee: U.S. Philips Corporation
    Inventors: Leonardus A. H. Van Hoof, Dieter Mateika, Horst Laudan, Johannes A. Pistorius, Jan Haisma
  • Single crystal of calcium-gallium germanium garnet and substrate manufactured from such a single crystal and having an epitaxially grown bubble domain film
    Patent number: 4323618
    Abstract: A novel non-magnetic monocrystalline garnet substrate material in the form of calcium--gallium-germanium garnet. Single crystals of calcium-gallium-germanium garnet can be grown at mush lower temperatures by means of the Czocharalski method than single crystals of the conventional rare earth-gallium garnets. These single crystals are very suitable to epitaxially grow bubble domain films thereon, in particular films on the basis of Lu.sub.3 Fe.sub.5 O.sub.12.
    Type: Grant
    Filed: February 13, 1978
    Date of Patent: April 6, 1982
    Assignee: U.S. Philips Corporation
    Inventors: Johannes P. M. Damen, Johannes A. Pistorius