Patents by Inventor Rolf Eric Rothfjell

Rolf Eric Rothfjell 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).

  • Method of deriving characteristic contours from a colored picture
    Patent number: 4055833
    Abstract: A method of deriving characteristic curves from a colored photograph of an object, which comprises making an image comprising only one of the basic colors of the colored photograph, the contrast of said image being enhanced, so that only the areas of the object which are most strongly colored in said color are reproduced.
    Type: Grant
    Filed: June 10, 1975
    Date of Patent: October 25, 1977
    Inventor: Rolf Eric Rothfjell