Tristimulus Examination Patents (Class 356/405)
  • Patent number: 4386267
    Abstract: The method allows the isolation of a certain portion of an original color picture having a color which corresponds to a reference color in a photoelectrical picture reproducing process. The colors of the original picture as well as the reference color are identified by using a color plane which is divided up into incremental areas. Since the computation process is simplified, the color isolation process can be accomplished at the same time as the original picture is photoelectrically scanned.
    Type: Grant
    Filed: October 15, 1980
    Date of Patent: May 31, 1983
    Assignee: Dainippon Screen Seizo Kabushiki Kaisha
    Inventor: Mitsuhiko Yamada
  • Patent number: 4349279
    Abstract: A method for the color evaluation of pattern models of fabric, decoration or packaging printing which, in particular, exhibit bleeding color areas, i.e. color areas of differing color saturation and/or brightness, and a color evaluation device with a color monitor is provided for carrying out the method. Color recognition signals characteristic for the individual pattern colors and a run signal, dependent on the respective color saturation, are derived from the color measured value signals obtained through opto-electric scanning of the pattern models. A freely-selectable color signal triad corresponding to the color to be displayed on the color monitor is assigned in a coloration unit to each pattern color and a further color signal triad is prescribed for the background color of the later printing medium. For displaying the pattern models on the color monitor, the color recognition signals in the coloration unit call in the color signal triads.
    Type: Grant
    Filed: December 10, 1979
    Date of Patent: September 14, 1982
    Assignee: Dr. Ing. Rudolf Hell GmbH
    Inventor: Eggert Jung
  • Patent number: 4307962
    Abstract: The invention relates to a method of determining the standard color data of colors represented on a color monitor. Within a color represented on the color monitor there is fixed a measurement area in which the color measurement data are determined. From the color measurement data there are calculated the corresponding standard color data of the color selected by the measurement area, taking into account the tube characteristics and the standard color data of the individual phosphors of the color monitor.The accuracy of the determination of standard color data can be increased by multiple measurement within the measurement area.The calculated standard color data are, for example, the starting quantities for a color mixture calculation by means of a color formula computer.
    Type: Grant
    Filed: August 27, 1979
    Date of Patent: December 29, 1981
    Assignee: Dr. Ing. Rudolf Hell GmbH
    Inventor: Eggert Jung
  • Patent number: 4278538
    Abstract: Workpieces (10; FIG. 7), differing from each other only in their color, are optically sorted by illuminating the workpieces with a light beam (13) of stable color temperature. The diffuse reflection from the workpieces is analyzed by three photo-detectors, each of which is filtered to respond to a different color. Two of the colors are primary colors, as defined by the Tristimulus Theory. The third color is not a true primary color but, when added to a percentage of one of the other two colors, effectively synthesizes the third primary color. A workpiece is identified by comparing the set of Tristimulus signals it generates with a look-up table stored in the memory (25) of a microprocessor (17).
    Type: Grant
    Filed: April 10, 1979
    Date of Patent: July 14, 1981
    Assignee: Western Electric Company, Inc.
    Inventors: Hopeton S. Lawrence, John D. Michalski
  • Patent number: 4256131
    Abstract: In a feedback color control system for controlling the flows of two colorants used to color an article, a first error signal is generated as a function of deviations in the color saturation of the article from a desired saturation, and a second error signal is generated as a function of deviations in the hue of the article from a desired hue. The flows of the dyes are varied in the same sense in response to the first error signal and are varied in opposite senses in response to the second error signal.
    Type: Grant
    Filed: September 8, 1978
    Date of Patent: March 17, 1981
    Assignee: Sentrol Systems Ltd.
    Inventor: Joseph De Remigis
  • Patent number: 4247202
    Abstract: A novel apparatus for the measurement of color of a sample which comprises an illumination means to illuminate the sample, an electro-optical sensing head to receive the light from the illuminated sample and to output electronic signals and an electronic processing unit to process the signals. The light source may in the preferred embodiment be the sun or the sample itself and a reference optical path is used for reference which is the same optical path as the optical path from the light from the sample. The tristimulus values X, Y, Z and the chromaticity coordinates x, y of the sample with respect to the CIE standards for luminance and chromaticity values are produced for accurate color measurement.
    Type: Grant
    Filed: June 25, 1979
    Date of Patent: January 27, 1981
    Assignee: Canadian Instrumentation and Research
    Inventor: Michael Failes
  • Patent number: 4165180
    Abstract: A novel apparatus for the measurement of color of a sample which comprises an illumination means to illuminate the sample, an electro-optical sensing head to receive the light from the illuminated sample and to output electronic signals and an electronic processing unit adapted to process the signals. The system uses, in the preferred embodiment, a moving spatial filter to modulate a spectrum and a masking means to selectively mask the light from the modulated spectrum. A reference optical path and reference light signals are produced for subsequent processing with the light from the sample, corrected for any errors produced and processed in an analogue electronic unit to produce the tristimulus values X, Y, Z and the chromaticity coordinates x, y of the sample with respect to CIE standards for luminance and chromaticity values.
    Type: Grant
    Filed: June 17, 1977
    Date of Patent: August 21, 1979
    Assignee: Canadian Instrumentation and Research Limited
    Inventor: Michael Failes
  • Patent number: 4131367
    Abstract: A tristimulus colorimeter employs a multiplexed dual slope integrator digital voltmeter wherein unknown and reference light beams are compared by sequentially applying unknown and reference electrical signals representative of the two respective light beams to the non-inverting and inverting inputs, respectively, of the integrator amplifier. Moreover, a compensating circuit provides for compensation of the colorimeter output signals with respect to reflectance error encountered in the optics portion of the colorimeter with such compensation being provided as a function of the light intensity from the colorimeter light source.
    Type: Grant
    Filed: November 2, 1976
    Date of Patent: December 26, 1978
    Assignee: Sterndent Corporation
    Inventors: Park French, William H. Conaway
  • Patent number: 4125329
    Abstract: A tristimulus colorimeter employs a multiplexed dual slope integrator digital voltmeter wherein unknown and reference light beams are compared by sequentially applying unknown and reference electrical signals representative of the two respective light beams to the non-inverting and inverting inputs, respectively, of the integrator amplifier. Moreover, a compensating circuit provides for compensation of the colorimeter output signals with respect to reflectance error encountered in the optics portion of the colorimeter.
    Type: Grant
    Filed: September 7, 1976
    Date of Patent: November 14, 1978
    Assignee: Sterndent Corporation
    Inventors: Park French, William H. Conaway