Patents by Inventor John Charles Brewer

John Charles Brewer 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).

  • Patent number: 5705327
    Abstract: Color negative photographic films having red, green and blue color sensitive records, wherein the ratio of the toe area contrast to the mid-scale contrast for each of the red, green and blue color records is less than or equal to 0.80, and either at least two color records having a toe-area contrast less than or equal to 0.42 or a mid-scale contrast less than or equal to 0.55, or the film having a speed rating of ISO 200 or greater. The mid-scale contrast for a color record is defined as the slope of a straight line connecting a point C and and a point D on the characteristic curve of Status M density versus log Exposure for the color record, where points C and D are located by defining a point A on the characteristic curve at a density level 0.1 above minimum density, a point B is located on the characteristic curve at an exposure value +1.0 Log Exposure beyond point A, and points C and D are located at exposure values -0.45 log Exposure and +0.45 log Exposure with respect to point B, respectively.
    Type: Grant
    Filed: September 16, 1996
    Date of Patent: January 6, 1998
    Assignee: Eastman Kodak Company
    Inventors: John Charles Brewer, John Tyler Keech, John Frank Sawyer
  • Patent number: 5674665
    Abstract: A color negative photographic film wherein on the curve of density versus log E for each color sensitive record: (1) a straight line, which connects the point at density Dmin+0.1 and the point at 1.5log E above the exposure required for density Dmin+0.2, has a mathematical slope .ltoreq. 0.50; and (2) the difference in log E is .gtoreq.1.7 between the point 0.9log E above the exposure required for density Dmin+0.2 and the point where the density difference is 0.1 between the curve and the straight line which results from a linear regression of the three density points at exposures 0.3log E, 0.9log E, and 1.5log E above the exposure required for the density Dmin+0.2; and (3) the difference in log E is .gtoreq.1.20 between the exposure needed for density Dmin+0.1 and the point that corresponds to the exposure, in lux-seconds, of 9.2/(Film Speed). The exposure of the foregoing gray card is a typical normal exposure based on the film speed rating (i.e. the film is not overexposed or underexposed).
    Type: Grant
    Filed: November 17, 1995
    Date of Patent: October 7, 1997
    Assignee: Eastman Kodak Company
    Inventors: John Frank Sawyer, Michael Paul Keyes, John Charles Brewer, John Tyler Keech, Elizabeth Laura Kelly