Patents by Inventor David M. Hopstock

David M. Hopstock 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).

  • Patent number: 6650815
    Abstract: The present invention relates to an optical fiber including a fiber core and at least one coating substantially encapsulating the fiber core, wherein the at least one coating includes a material forming a data storage medium which is capable of digitally encoding information at a data density of at least about 4 bits per centimeter. Both magnetically and optically encoded fibers are disclosed. Also disclosed are a method of making an optical fiber of the present invention, methods of digitally encoding information onto an optical fiber, and a method of retrieving information digitally encoded onto an optical fiber.
    Type: Grant
    Filed: September 18, 2001
    Date of Patent: November 18, 2003
    Assignee: Corning Incorporated
    Inventors: Daniel W. Hawtof, David M. Hopstock, Gregory F. Jacobs
  • Publication number: 20030026568
    Abstract: The present invention relates to an optical fiber including a fiber core and at least one coating substantially encapsulating the fiber core, wherein the at least one coating includes a material forming a data storage medium which is capable of digitally encoding information at a data density of at least about 4 bits per centimeter. Both magnetically and optically encoded fibers are disclosed. Also disclosed are a method of making an optical fiber of the present invention, methods of digitally encoding information onto an optical fiber, and a method of retrieving information digitally encoded onto an optical fiber.
    Type: Application
    Filed: September 18, 2001
    Publication date: February 6, 2003
    Inventors: Daniel W. Hawtof, David M. Hopstock, Gregory F. Jacobs
  • Patent number: 6468678
    Abstract: Magnetic, conformable articles for use with traffic bearing surfaces are disclosed which comprise an organic binder having magnetic particles distributed therein. The articles may be employed in intelligent vehicle guidance systems, and in systems to guide other mobile objects such as farm animals, pets, or visually impaired pedestrians. Methods of making the articles and methods of using the systems to control and/or guide a mobile object using the magnetic field generated from the articles are also described.
    Type: Grant
    Filed: October 22, 1997
    Date of Patent: October 22, 2002
    Assignee: 3M Innovative Properties Company
    Inventors: Thomas J. Dahlin, Gregory F. Jacobs, David M. Hopstock, Robert L. Keech, Richard E. Fayling, Richard G. Newell, Claud M. Lacey, Bernard A. Gonzalez
  • Patent number: 6253924
    Abstract: A magnetic separator apparatus for use in separating magnetic material from a mixture of at least magnetic material and a liquid includes an endless belt defining a channel. A portion of the endless belt is movable up an incline relative to horizontal through a separation zone. The endless belt includes an endless base section having a predetermined length and first and second sidewalls extending from the endless base section along the entire predetermined length thereof. The endless base section and the first and second sidewalls define the channel wherein the mixture is received. Further, the apparatus includes a ferromagnetic collection matrix positioned in the channel and one or more magnets positioned for generating a magnetic field in the separation zone. A method for use in separating magnetic material from a mixture using such an apparatus is also provided.
    Type: Grant
    Filed: November 10, 1998
    Date of Patent: July 3, 2001
    Assignee: Regents of the University of Minnesota
    Inventors: Rodney L. Bleifuss, David M. Hopstock
  • Patent number: 5853846
    Abstract: A conformable magnetic article for underlayment beneath a traffic-bearing surface which sends a magnetic signal to a sensor traveling over the traffic-bearing structure. The magnetic article comprises at least one conformable magnetic layer comprising a binder and a sufficient amount of magnetic particles dispersed within the binder to provide a magnetic signal through the traffic-bearing structure to a sensor.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: December 29, 1998
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Gary W. Clark, Thomas J. Dahlin, Richard E. Fayling, Bernard A. Gonzalez, David M. Hopstock, Gregory F. Jacobs, Robert L. Keech
  • Patent number: 5626956
    Abstract: The present invention provides a hexagonal magnetic ferrite pigment suitable for high density magnetic recording applications. The pigment is characterized by small particle size, a modified magnetoplumbite structure, and relatively high magnetic moment. The pigment is capable of being prepared by firing suitable precursor particles in air at temperatures below 850.degree. C.
    Type: Grant
    Filed: December 28, 1993
    Date of Patent: May 6, 1997
    Assignee: Imation Corp.
    Inventors: David M. Hopstock, John S. Roden, Gunther H. Dierssen, Ronald S. Sapieszko
  • Patent number: 5616414
    Abstract: The present invention provides a hexagonal magnetic ferrite pigment suitable for high density magnetic recording applications. The pigment is characterized by small particle size, a modified magnetoplumbite structure, and relatively high magnetic moment. The pigment is capable of being prepared by firing suitable precursor particles in air at temperatures below 850.degree. C.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: April 1, 1997
    Assignee: Imation Corp.
    Inventors: David M. Hopstock, John S. Roden, Gunther H. Dierssen, Ronald S. Sapieszko
  • Patent number: 5378384
    Abstract: The present invention provides a hexagonal magnetic ferrite pigment suitable for high density magnetic recording applications. The pigment is characterized by small particle size, a modified magnetoplumbite structure, and relatively high magnetic moment. The pigment is capable of being prepared by firing suitable precursor particles in air at temperatures below 850.degree. C.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: January 3, 1995
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: David M. Hopstock, John S. Roden, Gunther H. Dierssen, Ronald S. Sapieszko
  • Patent number: 4192738
    Abstract: There is disclosed a process for scavenging iron from tailings produced by the flotation beneficiation of iron ore. This process includes the step of scavenging the flotation tailings using wet high-intensity magnetic separation (WHIMS). There is also disclosed a process for increasing the recovery of iron ore in a flotation beneficiation process. This iron ore recovery process includes the steps of feeding the magnetic concentrate produced by the scavenging process to a flotation system and then carrying out an additional flotation step.
    Type: Grant
    Filed: October 23, 1978
    Date of Patent: March 11, 1980
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: Arthur F. Colombo, David M. Hopstock