Patents by Inventor Dan K. Marker

Dan K. Marker 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: 6752502
    Abstract: An optical quality, freestanding, compliant membrane mirror is cast with a concave parabolic shape, and includes a substrate and a reflective stress coating. The stress coating is in compression and applies a tensile shear stress to the substrate that opposes and offsets the intrinsic stress in the substrate that would otherwise decrease the concavity. The stress coating generates a force to restore the membrane mirror to its cast concave parabolic shape when an external force deforms the mirror.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: June 22, 2004
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Richard A. Carreras, Dan K. Marker, James M. Wilkes, Dennis Duneman, James R. Rotge
  • Publication number: 20030223135
    Abstract: A method for fabricating an optical quality, free-standing, compliant parabolic membrane mirror is described using an inverted parabolic mandrel created by rotating a liquid confined to a cylindrical container, forming a membrane substrate by pouring into the mandrel a fast curing liquid polymer and applying a reflective optical stress coating once the substrate has hardened.
    Type: Application
    Filed: March 17, 2003
    Publication date: December 4, 2003
    Inventors: Richard A. Carreras, Dan K. Marker, James M. Wilkes, Dennis Duneman, James R. Rotge
  • Patent number: 6533426
    Abstract: A method for fabricating an optical quality, free-standing, compliant parabolic membrane mirror using an inverted parabolic mandrel created by rotating a liquid confined to a cylindrical polymer and applying a reflective optical stress coating once the substrate has hardened. The stress coating applies a tensile force to the substrate that offsets the stress in the substrate that would otherwise decrease the convexity, and also generates a force to restore the membrane mirror to its original convex parabolic shape when the mirror is deformed by an external force.
    Type: Grant
    Filed: May 2, 2001
    Date of Patent: March 18, 2003
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Richard A. Carreras, Dan K. Marker, James M. Wilkes, Dennis Duneman, James R. Rotge
  • Publication number: 20020163744
    Abstract: Attorney Docket No. PRS0586A method for fabricating an optical quality, free-standing, compliant parabolic membrane mirror is described using an inverted parabolic mandrel created by rotating a liquid confined to a cylindrical container, forming a membrane substrate by pouring into the mandrel a fast curing liquid polymer and applying a reflective optical stress coating once the substrate has hardened.
    Type: Application
    Filed: May 2, 2001
    Publication date: November 7, 2002
    Inventors: Richard A. Carreras, Dan K. Marker, James M. Wilkes, Dennis Duneman, James R. Rotge
  • Patent number: 6332687
    Abstract: A membrane mirror having an optical quality spherical shape maintained by differential pressure takes a near parabolic shape when a plunger-induced displacement of the central area of the mirror is introduced. The focal length can be adjusted by varying the differential pressure.
    Type: Grant
    Filed: November 2, 2000
    Date of Patent: December 25, 2001
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Richard A. Carreras, Dan K. Marker, James M. Wilkes, Dennis Duneman, James R. Rotge
  • Patent number: 6113242
    Abstract: A thin membrane is mounted on an optically flat circular outer ring and stretched over a smaller optically flat circular inner ring. Differential pressure is applied to the annulus formed between the inner and outer rings to prestrain the membrane and separately applied to the inner ring where the mirror figure will be produced. The inner ring has a doubly curved top surface and is optically fiat so that the membrane can freely move across the inner ring as incremental stress is applied via the annulus. A calculated combination of annulus stress and differential pressure on the inner ring produces an optical quality mirror figure in the inner ring area.
    Type: Grant
    Filed: January 15, 1999
    Date of Patent: September 5, 2000
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Dan K. Marker, Richard A. Carreras, James M. Wilkes, Dennis Duneman