Patents by Inventor Keith C. Campbell

Keith C. Campbell 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: 7892634
    Abstract: The 3-D relief pattern blank and method of using comprises the steps of using a cutting machine to cut a thin, retroreflective heat reflective sheet in a desired pattern. The thin, retroreflective heat reflective sheet is formed to provide a heat-retroreflective mask. Subsequently, the heat-retroreflective mask is transferred to a preferably smooth surface of a foamed thermoplastic substrate. The assembly of heat-retroreflective mask and foamed thermoplastic is then exposed to a source of visible and/or infrared radiation. The radiation does not have to be coherent and the exposure need not be under automatic guidance or control. Unmasked areas of the foamed thermoplastic absorb radiant heat more rapidly than masked areas, causing the unmasked areas to collapse into a relief of the desired pattern. The resulting relief ranges between approximately an eighth of an inch and one inch in depth.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: February 22, 2011
    Inventor: Keith C. Campbell
  • Publication number: 20070292807
    Abstract: The 3-D relief pattern blank and method of using comprises the steps of using a cutting machine to cut a thin, retroreflective heat reflective sheet in a desired pattern. The thin, retroreflective heat reflective sheet is formed to provide a heat-retroreflective mask. Subsequently, the heat-retroreflective mask is transferred to a preferably smooth surface of a foamed thermoplastic substrate. The assembly of heat-retroreflective mask and foamed thermoplastic is then exposed to a source of visible and/or infrared radiation. The radiation does not have to be coherent and the exposure need not be under automatic guidance or control. Unmasked areas of the foamed thermoplastic absorb radiant heat more rapidly than masked areas, causing the unmasked areas to collapse into a relief of the desired pattern. The resulting relief ranges between approximately an eighth of an inch and one inch in depth.
    Type: Application
    Filed: May 30, 2007
    Publication date: December 20, 2007
    Inventor: Keith C. Campbell