First and second measurement operations are performed according to each of a plurality of geometric conditions while keeping the geometric condition. In the first measurement operation, illumination light is radiated from a first light radiating position toward a measurement target position and spectroscopic measurement is performed on reflected light traveling from the measurement target position toward a first light receiving position. In the second measurement operation, illumination light is radiated from a second light radiating position toward a measurement target position and spectroscopic measurement is performed on reflected light traveling from the measurement target position toward a second light receiving position. The two spectroscopic measurement results are averaged. The second light radiating position and the second light receiving position are respectively disposed symmetrical to the first light radiating position and the first light receiving position with respect to a reference axis.

A computer system for analyzing a paint sample and generating values that describe various attributes of a proposed matching color can comprise instructions for receiving from a coating-measurement instrument one or more coating variables of a target coating. The system can also comprise instructions for calculating coating texture ratings for the multiple respective proposed coating matches. The coating texture ratings can indicate a similarity between the one or more coating texture characteristics of the target coating and respective coating texture characteristics of each of the respective proposed coating matches. Additionally, the system can comprise instructions for sending instructions to generate a user interface that depicts overall rankings of at least a portion of the proposed coating matches. The overall rankings indicate a similarity between the target coating and each of the at least a portion of the proposed coating matches with respect to the coating texture ratings.

A system for the automatic grading of a cut/polished gemstone (SUT) includes an enclosure with a stage for mounting the cut/polished SUT. The enclosure further includes one or more sources of broadband visible (BBV) light, the sources of BBV light being controllable by a programmable controller; an image sensor for capturing a plurality of images of a mounted SUT, and one or more sources of UV light mounted within the enclosure. The controller captures images of the mounted SUT from one or more selected angles relative to the sensor elevation axis and relative to the position of the SUT on the stage rotation axis; an image capturing module is configured for processing the one or more images; and, a light grade calculation module is configured for grading the cut/polished SUT using light indicative parameters from at least a part of the one or more images captured.

Embodiments of the invention generally relate to color and appearance metric measurements and, in particular, developing instrumentation to enable self-consistent image appearance measurements within instruments of unitary construction.

A computer system for seeding a formulation engine receives spectrometric data from a target coating. The computer system processes the spectrometric data through a probabilistic colorant analysis. The probabilistic colorant analysis generates a set of colorants. Each colorant within the set of colorants is associated with a calculated probability that the associated colorant is present within the target coating. Additionally, the computer system adds at least a portion of the colorants within the set of colorants to a formulation engine. The portion of the colorants is added to the formulation engine in order of decreasing probability. Further, the computer system generates, from an output of the formulation engine, a coating formulation that is calculated to match the target coating within a predetermined qualitative threshold.

A method that includes obtaining, using a processor, image data from a target coating. The method also includes performing, using the processor, an image analysis to determine at least one sparkle point from the image data, and performing, using the processor, a hue analysis to determine a sparkle color from the sparkle point. The method further includes calculating, using the processor, a sparkle color distribution, and generating, using the processor, a coating formulation that is the same or substantially similar in appearance to the target coating.

Apparatuses and methods for measurement of spatial properties of a moving surface coating containing flake pigment are provided herein. An exemplary apparatus includes a movable surface adapted to receive the surface coating. A motion device is in mechanical communication with the movable surface. A light source provides a beam of light directed at a preselected interrogation zone through which the movable surface passes during movement thereof. A light detection device detects light reflected from the preselected interrogation zone and produces an output. A computing device is configured to determine one or more spatial properties of the surface coating based upon the output. One or more of the light source, the light detection device, or the computing device are configured to adjust for the movement of the surface coating through the preselected interrogation zone as a variable that affects measurement of reflected light by the light detection device.

Apparatuses and methods for approximating a 5-angle color difference model are provided, where the 5-angle color difference model utilizes a 5-angle equation. In an exemplary embodiment, an apparatus includes a storage device for storing instructions and one or more processors configured to execute the instructions. The processor(s) are configured to receive 3-angle standard and test color measurements, and enter the 3-angle standard measurement into a neural network empirical model. The neural network empirical model includes a plurality of input nodes, a plurality of hidden nodes connected to the input nodes, and a plurality of output nodes connected to the hidden nodes. The neural network empirical model is configured to output 3-angle tolerance values, and to calculate a 3-angle color difference value using the 5-angle equation for at least one of the 3 color measurement angles using the 3-angle standard and test color measurements and the 3-angle tolerance values.

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.

An evaluating method includes obtaining, by an imaging device, a two-dimensional reflected light amount distribution of a surface of a target; classifying, by one or more processors, the surface into a plurality of areas on the basis of chromaticity information of the two-dimensional reflected light amount distribution; and evaluating, by one or more processors, appearance characteristics of the target on the basis of respective sets of chromaticity information of the areas.