Abstract:
A computer-implemented intelligent alignment method for a color sensing device (12) which initially obtains a raw sense value measured by the color sensing device and converts the raw sense value to a tristimulus value (S401). The color sensing device may be calibrated using a known set of colors (S402). Raw readings received from the color sensing device may be mapped to known tristimulus values (S403), and mapped values may be converted to a standard reference illuminant color space (S404). A client-server system may be provided in which a color sensing device and one or more servers collectively execute operations according to the present disclosure.
Abstract:
This specification describes various embodiments that relate to methods for providing a wideband colorimeter that can include more accurate outputs. In one embodiment, a narrowband instrument, such as a spectrometer or spectrograph, can be used for calibration of a wideband colorimeter, so that more accurate outputs can be provided. In one embodiment, an optical test equipment, which consists of both a wideband colorimeter and a narrowband spectrograph, can be used for providing a more accurately calibrated wideband colorimeter. As an example, a spectra-camera, which is a hybrid system consisting of both a wideband colorimeter and a narrowband spectrograph, can be used for simultaneous testing by both the wideband colorimeter and the narrowband spectrograph. By doing simultaneous testing, accurate calibration of the wideband colorimeter can be achieved. This specification further describes a mathematical model to characterize a wideband three channel colorimeter with a narrowband multiple channel spectrometer.
Abstract:
A method is provided for testing a diffusely reflective liquid for colour strength, said liquid comprising particles in a carrier medium,e.g. white emulsion paint based on titanium dioxide. The method comprises measuring in situ a lightness parameter of the liquid, of the carrier medium and of the liquid diluted with amounts of carrier medium; and determining from said measurements a dilution parameter indicating the amount of carrier medium needed to produce a predetermined reduction in the lightness parameter of the liquid, said dilution parameter providing an indication of colour strength. The lightness parameter may be L* in the CIE L*, a*, b* colour space, and the test may be carried out using a diffuse reflection probe configured to direct light from said probe into the liquid and configured to collect a portion of the light from the probe diffusely reflected by the paint for determining the lightness parameter. The results may be used for process control e.g. in emulsion paint manufacture.
Abstract:
Preferably, seven classes of observers are defined, according to different sets of Colour Matching Functions. By displaying specific colour patches of a classification chart using colour display devices having different sets of primaries, and by asking an actual observer to compare his perception of the same colour as displayed on each colour display device, the method allows assigning said observer his specific class. It is proposed a specific apparatus to implement this method.
Abstract:
Ein Bildaufnehmer für die digitale Aufnahme eines zweidimensionalen Farbbildes weist mehrere lichtempfindliche Sensorpixel (26) und mehrere nebeneinander angeordnete Farbteiler-Elementen (24) auf, wobei jedem Farbteiler-Element (24) mindestens zwei Sensorpixel (26) zugeordnet sind. Ferner ist jedes Farbteiler-Element (24) derart ausgebildet, dass es darauf auftreffendes polychromatisches Licht (34) auf die ihm zugeordneten Sensorpixel (26) mit einem Aufteilungsverhältnis verteilt, das von der spektralen Zusammensetzung des auftreffenden Lichts abhängt. Erfindungsgemäß sind die Farbteiler-Elemente (24) in einem zweidimensionalen Muster angeordnet.
Abstract:
A method for characterizing a color in terms of tristimulus values, the method includes providing a source of a color; measuring a set of spectral values for color stimulus associated with the color using a spectral measurement device controlled by a digital processing system; calculating a first set of tristimulus values from the set of spectral values; defining a set of human observer color matching functions, the set of human observer color matching functions being functions of the tristimulus values; and determining a second set of tristimulus values from the set of spectral values using set of human observer color matching functions.