Patents by Inventor Dorothee Griesch

Dorothee Griesch 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).

  • Methods and apparatus for automatic exposure control
    Patent number: 4093375
    Abstract: This invention relates to a method of exposure control in photographic printing apparatus for printing from originals made on different types of photographic material, the method comprising:Determining which of at least two types (such as silver halide or diazo film) of photographic material the original employs by an examination of the spectral transmission characteristics of the original,Determining the image density of the original, andControlling the exposure in accordance with both the type of material as determined and the image density.
    Type: Grant
    Filed: April 26, 1976
    Date of Patent: June 6, 1978
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Dorothee Griesch, Herbert Schroter, Peter Schwagler, Eckehard Stein