A device such as a stylus may have a color sensor. The color sensor may have a color sensing light detector having a plurality of photodetectors each of which measures light for a different respective color channel. The color sensor may also have a light emitter. The light emitter may have an adjustable light spectrum. The light spectrum may be adjusted during color sensing measurements using information such as ambient light color measurements made with a color ambient light sensor that has a plurality of photodetectors each of which measures light for a different respective color channel. An inertial measurement unit may be used to measure the angular orientation between the stylus and an external object during color measurements. Arrangements in which the light emitter is modulated during color sensing may also be used. Measurements from the stylus may be transmitted wirelessly to external equipment.

A method for color shade matching obtains a 3D tooth surface representation using an intraoral scanner wherein the 3D tooth surface representation comprises surface data and a spatially resolved angular distribution of color vectors, wherein the spatially resolved angular distribution of color vectors associates one or more point positions from the surface data to the corresponding angular distribution of color vectors. The method identifies one or more shade values, where each shade value is associated with one angular distribution of color vectors from the spatially resolved angular distribution of color vectors, by comparing the angular distribution of color vectors to a set of reference angular distributions of color vectors, wherein each reference angular distribution in the set is associated with a corresponding shade value. The method displays, stores, or transmits the surface data with an indication of the one or more shade values.

A custom-tint paint production system that includes a color sensing device such as a low-resolution spectrophotometer to measure color of a preexisting surface color, a color data translation engine to convert the measured values to spectral curve values, and a tint formulation engine to determine a custom tint formulation based upon the spectral curve values, which is usable by a tinter to tint a base coating composition by adding one or more colorants in amounts based on color measurements from the color sensing device.

A computer implemented method. The method includes generating, using a processor, a set of calibration data relating to a plurality of pigments that are present in a collection of coatings. Generating includes calculating an absorption/reflectance relationship of a plurality of samples coated with a plurality of the pigments, wherein calculating includes using a color matching calculation, and calculating a plurality of concentrations of a non-standard pigment. Generating also includes plotting a relationship between the concentrations and the absorption/reflectance relationships, and determining a correlation of the concentrations for a plurality of Fresnel coefficients relating to the samples. The method further includes determining, using the processor, a coating formulation of a target coating based on the correlation.

The present invention relates to a method for determining a characteristic number for characterizing the quality of a shade setting of a paint in relation to a color reference, characterized in that colorimetric coordinates of the paint and of the color reference are determined with a spectrophotometer for a number of measurement geometries and wherein respective color differences are calculated and standardized from the colorimetric coordinates of the paint and of the color reference for each measurement geometry of the number of measurement geometries, and where a group of characteristic values calculated from the respective standardized color differences is assigned a scale value for determining the characteristic number by means of an assignment rule to be provided in advance.

The invention relates to a method of displaying an image of an effect coating having texture and color properties on an electronic display device, using measured color data and measured texture data as input to generate the image, wherein the textured image is displayed with visual color properties which are maintained on a prescribed level independent of possible variations in texture properties.

A method for calculating a coating textures indicator can comprise receiving target coating texture variables from an image. The method can also comprise accessing a relative texture characteristic database that stores a set of texture characteristic relationships for a plurality of coatings. The method can further comprise calculating a correlation between the target coating texture variables and target coating texture variables associated with a compared coating. Based upon the calculated correlation, the method can comprise, calculating a set of relative texture characteristics for the target coating that indicate relative differences in texture between the target coating and the compared coating. Each of the relative texture characteristics can comprise an assessment over all angles of the target coating.

A computerized method for displaying matches of a paint sample to various proposed paint coatings includes receiving one or more coating texture variables of a target coating from a coating-measurement instrument. The method also includes displaying, on a digital display device, effect texture ratings for multiple respective proposed coating matches on a digital display device, wherein the effect texture ratings indicate a similarity between the one or more coating texture variables of the target coating and respective coating textures variables of each of the respective proposed coating matches. In addition, the method includes ordering the proposed coating matches, wherein the ordering indicates a strength in similarity between the target coating and each of the proposed coating matches with respect to the effect texture ratings.

A process for producing a total match metric for matching color and appearance of a target coating and at least a specimen coating is provided. The total match metric (TMM) are produced based on color difference values (ΔE) at three or more color viewing angles, sparkle difference values (ΔS) at one or more sparkle viewing angles and flop difference value (Δf) between the target coating and the specimen coating using one or more linear functions, one or more non-linear functions, or a combination thereof. The total match metric can be used in producing matching coatings that match color and appearance of the target coating. The total match metric can be particularly useful for repair coating damages to vehicles.

Disclosed in a method, a user interface and a system for use in determining shade of a patient's tooth, wherein a digital 3D representation including shape data and texture data for the tooth is obtained. A tooth shade value for at least one point on the tooth is determined based on the texture data of the corresponding point of the digital 3D representation and on known texture values of one or more reference tooth shade values.