Patents by Inventor Ernest J. Twigger

Ernest J. Twigger 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).

  • Daylight enlarger
    Patent number: 4552452
    Abstract: A daylight enlarger of the enclosed image-framing area type wherein the image framing area is enclosed by solid curtain walls having at least one light-tight arm-hole therein and wherein part of one of the walls encompasses in a light-tight manner a removable actinic light opaque processing dish having a lid which when the dish is present in the wall can be opened to enable print material to be placed therein and which can be closed from inside the enclosed image framing area.
    Type: Grant
    Filed: July 5, 1983
    Date of Patent: November 12, 1985
    Assignee: Ciba-Geigy AG
    Inventors: George F. A. M. Turner, Michael H. Moore, Ernest J. Twigger