Patents by Inventor Frank J. Merrick

Frank J. Merrick 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).

  • Pinhole camera with adjustable focal length
    Patent number: 5023641
    Abstract: The invention pertains to cameras and more particularly to pinhole cameras. A method is provided whereby the focal length of a pinhole camera may be adjusted by varying the distance between the pinhole, functioning as the lens, and the photographic paper, serving as film. This adjustment may be made by the user any time before exposure.
    Type: Grant
    Filed: September 14, 1990
    Date of Patent: June 11, 1991
    Inventor: Frank J. Merrick