Lexmark International, Inc.

Xuan-Chao Huang

Brant Dennis Nystrom

Richard Lee Reel

Anna Yaping Deer

Yao Han

Ajay Kanubhai Suthar

Xiaorong Cai

Jamee Casteel Holiway

Jincheng Huan

A method for converting a source gamut of an image to a destination gamut includes providing an imaging apparatus having a plurality of destination gamuts, determining a source gamut boundary for the source gamut of the image; selecting an appropriate destination gamut from the plurality of destination gamuts based on a desired output; mapping to the appropriate destination gamut based at least in part on the source gamut boundary; and determining a color conversion lookup table based on the mapping to the appropriate destination gamut for use in replicating the image to provide the desired output using the imaging apparatus.

Method for converting a source gamut of an image to a destination gamut

A method of gamut mapping includes the steps of defining a mapping function establishing a continuous first derivative of change of at least one color space component from a first color gamut to a second color gamut, and applying the function to first color gamut data for the at least one color space component.

Gamut mapping by controlling minimum and maximum color changes

A printhead auto-alignment detection system includes a UV LED configured and positioned to transmit light in ultraviolet wavelengths onto a printed printhead alignment pattern formed using an aqueous ink having a UV fluorescing material. A sensor is configured and positioned to detect light in visible wavelengths emitted by the fluorescing material. A controller is communicatively coupled to the UV LED and the sensor. The controller is configured to execute program instructions for controlling the output of the UV LED and for reading a signal output of the sensor during a printhead alignment operation.

Printhead auto-alignment detection system that uses a printed printhead alignment pattern cotaining fluorescing material

A method for correcting neutral color shift in a production cartridge for use in an imaging system includes determining a colorant increment data based on a standard cartridge neutral variation signature color data and a standard cartridge neutral sensitivity signature color data associated with a standard cartridge, and based on a production cartridge neutral variation signature color data and a production cartridge neutral sensitivity signature color data associated with the production cartridge, and using the colorant increment data to correct the neutral color shift.

Method of correcting neutral color shifts caused by cartridge variations

A method of selecting inks for use in imaging with an imaging apparatus includes establishing a high fidelity colorant cube having a plurality of vertex lines pertaining to a corresponding plurality of basic inks, and at least one other vertex line pertaining to at least one high fidelity ink; determining first mixing coordinates of the at least one high fidelity ink and the plurality of basic inks for face grids of the high fidelity colorant cube based on a maximum permitted ink amount; determining second mixing coordinates of the at least one high fidelity ink and the plurality of basic inks for interior grids of the high fidelity colorant cube based on the maximum permitted ink amount; and generating a color conversion lookup table based on the first mixing coordinates and the second mixing coordinates for printing with the imaging apparatus.

Method of selecting inks for use in imaging with an imaging apparatus

A method of selecting inks for use in imaging with an imaging apparatus includes determining a maximum usage of a diluted ink for use in conjunction with a saturated ink based on visual perception characteristics relating to a combination of the diluted ink and the saturated ink; generating an initial colorant space based on the maximum usage of the diluted ink, the initial colorant space expressing an initial usage of the diluted ink and an initial usage of the saturated ink at each point in the initial colorant space; optimizing the initial usage of the diluted ink and the initial usage of the saturated ink in the initial colorant space to generate a final usage of the diluted ink and a final usage of the saturated ink in a final colorant space; and generating a color conversion lookup table based on the final colorant space.

A method of correcting color shift caused by printing with an imaging system using a first cartridge and a second cartridge different from the first cartridge includes determining individual cartridge characterization data based on each of the first cartridge and the second cartridge individually; determining combined cartridge characterization data that characterizes a usage combination of the first cartridge and the second cartridge; and determining color correction data based on the individual cartridge characterization data and the combined cartridge characterization data.

Method and system for correcting color shift caused by printing with an imaging system using multiple cartridges

An electronic representation of the range of color combinations that can be displayed on the monitor is created and printed. The printed representation is then scanned by the scanner. A relationship is then identified between the monitor and the scanner. This relationship is then used as the basis to determine a relationship between the scanner and the monitor. Compensation is made for errors and the relationship is further developed. Finally, a scanner RGB to printer CMYK lookup table is built.

Method of calibrating a scanner to a printer

A method for calibrating a production printing cartridge for use in an imaging system includes the steps of obtaining first standard cartridge signature color data associated with a standard printing cartridge and a first substrate, obtaining second standard cartridge signature color data associated with the standard printing cartridge and a second substrate, obtaining first production cartridge signature color data associated with the production printing cartridge and the first substrate, and estimating second production cartridge signature color data associated with the production printing cartridge and the second substrate based on the first standard cartridge signature color data, the second standard cartridge signature color data, and the first production cartridge signature color data.

Method for calibrating production printing cartridges for use in an imaging system

A computerized method for mixing inks to facilitate high fidelity color reproduction for printing includes the steps of using a theoretical printer model to establish relationship between the colorant space and the color space using the small number of measurements; building a simplified colorant space wherein each color in the color space corresponds to only one colorant point; sampling the color space for accurate calibration; performing interpolation and correction for any non-calibrated points based on the theoretical and experimental results; and building a color reproduction table that accepts image data as input and output colorant combinations for use by the printer to achieve high fidelity color printing.

Method for mixing inks for high fidelity color printing

A method for mixing ink for use in an imaging apparatus including an ink jet printer capable of printing a plurality of primary color inks includes the steps of identifying available printing levels for each of the primary color inks, determining a target color profile for each of the primary color inks, and determining a graininess factor for each printing level. A mixing order is set up for at least some of the available printing levels, based in part on corresponding graininess factors and at least one mixing rule. At least a portion of the plurality of available printing levels is mixed, based on the mixing order and the target color profile, generating a plurality of mixing tables. Each mixing table corresponds to one of each of the primary color inks.

Method of mixing multi-level black and color inks in a printing system

Data in only three colors is printed in the three colors plus black. The coverage amount represented by the smallest intensity of the three colors is determined. When that amount is above a predetermined value at which observable grain becomes minimal, an exponent value is determined and a formula is followed. As an additional improvement, lightness is redefined on a model which favors less black at the lighter values and more black at the darker values. Hue is to remain the same, and is known from the original color data. The chroma is refined based on the original chroma, CMY and CMYK full gamut boundaries. Since black, lightness, chroma and hue are known, the new three color values are found by known techniques.

Printing black and three colors from three color data

An improved &ldquo;scattered data transformation&rdquo; method for warping/morphing color data is provided to transform n-dimensional data so that only selected regions of the n-color space are modified. The method uses a set of &ldquo;input points&rdquo; that are chosen to represent the color gamut for an input color space. In addition, a set of &ldquo;training points&rdquo; having associated &ldquo;training vectors&rdquo; are chosen in the input color space, and the training points are used to define the transform output for the input points in the color input space. Some (or all) of the input points may also be training points, but it is not necessary that any of the input points be training points. The vector displacement effect of the preferred embodiment is both exponentially and inversely proportional to the distance of each of the input points to one or more of the training points so that, the closer a training point is to an input point, the greater the effect of that training point on that input point. If a training point is located beyond a pre-determined distance from an input point, then it will have no effect at all on that input point. A refinement of the present invention is to weight the vectors for the training points, so that certain training points can become much more &ldquo;important&rdquo; than others when modifying the input color space to the output color space.

Method for morphing n-dimensional data using a scattered data transformation

A device and method of determining an amount of ink to be used to print a color of a particular color lightness, chroma and hue in an inkjet printer in which the color lightness, chroma and hue are measured for a full ink wedge and a reduced ink wedge for a given color. The full ink wedge uses the maximum amount of ink for the given color and causes bleed through or smearing to occur and the reduced ink wedge uses less than the maximum amount of ink for the given color. A color difference between the reduced ink wedge and the full ink wedge is calculated. A vector distance between the reduced ink wedge and a white point in a three-dimensional colorant space is then calculated. Calibration points for each colorant or colorant combination in a three-dimensional colorant space are determined based on the vector distance, the color difference, and the predetermined color tolerance. A printer profile table is then generated using these new calibration points and downloaded to the printer. Printing using a reduced ink volume is then accomplished using the printer profile table.

Ink reduction device and method for a color inkjet printer

A device and method of printing a color image using a lookup table that indicates the amount of at least two concentrations of a given ink color to use. Initially, several color wedges made from uniformly distributed digital counts for each color from lightest to darkest are printed. The color lightness value for each wedge is then measured as an L* value of the CIELAB system along with a granularity value. An interpolation process is then performed to determine the color lightness values and granularity values for color values between wedges. A diluted ink minimum color lightness point is identified by determining the darkest color that can be generated using only diluted ink. Ink patterns are then selected using only diluted ink for color lightness values lighter than the diluted ink minimum lightness point in the lookup table. A zero diluted ink starting point is then identified by determining that granularity improvement cannot be achieved significantly when adding more diluted ink to a pixel matrix. Ink patterns are then selected using a mixture of diluted and saturated ink that gives a print image within a predetermined percentage of a target color lightness value and within a predetermined percentage of the granularity of the pixel matrix using an optimum amount of diluted ink. Finally, ink patterns are selected using only saturated ink for color lightness values darker than the zero diluted ink starting point in the look up table.

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Lexington, KY, United States of America

Xuan-Chao Huang