Patents by Inventor Mark Dempster

Mark Dempster 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).

  • TENT FEATURING RETRACTABLE ROOF AND SIDE CANVAS PANELS OR SHEETS
    Publication number: 20230065753
    Abstract: Retractable roof and/or wall panels are disclosed herein. Such panels may be used as roof or wall portions for tents or other temporary structures allowing for variable outdoor exposure and easy transitions from indoor to outdoor spaces.
    Type: Application
    Filed: August 31, 2021
    Publication date: March 2, 2023
    Inventors: Guy Stuart Ritchie, Allister Mark Dempster, Rupert Wilson Charles-Jones
  • Display device
    Patent number: 4969732
    Abstract: A display device includes equipment for projecting light onto a surface. The equipment includes a beam-splitter for effecting partial reflection and partial transmittance of an incident beam. On one side of the beam-splitter are a light source for directing light onto the beam-splitter and a mirror for directing back towards the beam-splitter light reflected therefrom. On the other side of the beam-splitter is a louvre for permitting passage therethrough of light of incident angle relative to a normal to the beam-splitter with in a predetermined restricted range.
    Type: Grant
    Filed: February 23, 1989
    Date of Patent: November 13, 1990
    Assignee: Thorn EMI plc
    Inventors: Graham L. Wright, Mark Dempster