Abstract: A calorimeter for measuring a color of light includes a color sensing device, a suspension means and a counterweight. The suspension means suspends the color sensing device in an operative relationship relative to a color producing device, while the counterweight is secured to the suspension means and balances the color sensing device in the operative relationship relative to the color producing device.

Abstract: A color luminance meter 1 is provided with a polychrometer 4 as a spectral optical system including a light receiving sensor array 43, a signal processing circuit 5 and an operation control unit 6. The operation control unit 6 carries out calculations to obtain characteristics of a measurement light based on a specified spectral responsitivity, using light reception signals and specified weighting coefficients. The spectral responsitivities of light receiving sensors constructing the light receiving sensor array 43 are selected such that B?5 nm and A/B lies within a range of 1.5 to 4.0 when A, B denote the half power band width of the spectral responsitivities and a center wavelength interval of the spectral responsitivities. Accordingly, there can be provided a light measuring apparatus capable of maximally suppressing errors to highly precisely measure color luminance values and the like even in a measurement of a light lying in a narrow band such as a monochromatic light.

Abstract: Methods are provided for detecting compression wood, blue stain, or pitch in lumber. A light beam is projected towards the wood sample. Line or area cameras acquire images of light that is reflected from the wood sample. Based on the intensity of the reflected light at one or more locations on the wood sample, compression wood, blue stain, or pitch may be detected.

Abstract: An output current from each pixel sensor can be extracted at an arbitrary ratio by a current divider. An arithmetic control unit sets the dividing ratio in correspondence to a color matching function. The current components are added together by a summing amplifier so that a signal corresponding to a tristimulus value is composed and then converted into a digital signal. That is, weighting by weight factors corresponding to color matching functions of CIE 2-degree observer is performed in a stage of analog signal processing.

Abstract: The Apparatus for determining the color stimulus specification of a translucent object, for example of a tooth, comprises an illumination device as well as an image capture device. For illuminating the object under test with light in different wave length portions, the illumination device comprises an LED array with a plurality of sequentially energizable light emitting diodes. Several different types of light emitting diodes are provided, each emitting light in a different wave length portion.

Abstract: Methods are provided for detecting compression wood, blue stain, or pitch in lumber. A light beam is projected towards the wood sample. Line or area cameras acquire images of light that is reflected from the wood sample. Based on the intensity of the reflected light at one or more locations on the wood sample, compression wood, blue stain, or pitch may be detected.

Abstract: A miniaturized spectrometer/spectrophotometer system and methods are disclosed. A probe tip including one or more light sources and a plurality of light receivers is provided. A first spectrometer system receives light from a first set of the plurality of light receivers. A second spectrometer system receives light from a second set of the plurality of light receivers. A processor, wherein the processor receives data generated by the first spectrometer system and the second spectrometer system, wherein an optical measurement of a sample under test is produced based on the data generated by the first and second spectrometer systems. Improved shade matching/prediction results are obtained through the use of volumes/regions, preferably polygons, around shades in a shade system.

Abstract: A miniaturized spectrometer/spectrophotometer system and methods are disclosed. A probe tip including one or more light sources and a plurality of light receivers is provided. A first spectrometer system receives light from a first set of the plurality of light receivers. A second spectrometer system receives light from a second set of the plurality of light receivers. A processor, wherein the processor receives data generated by the first spectrometer system and the second spectrometer system, wherein an optical measurement of a sample under test is produced based on the data generated by the first and second spectrometer systems.

Abstract: Method and apparatus for estimating surface moisture content of wood chips employing a surface moisture measurement obtained from a non-contact surface moisture sensor, which measurement is calibrated with values of a set of optical parameters, such as HSL color camera signals, representing light reflection characteristics of the wood chips in order to estimate the surface moisture content thereof.

Abstract: A method for generating a calculation formula to obtain an accurate mottling value is disclosed. Two-dimensional data and color values of a target paint film are considered. The calculation formula provides a method for numerically expressing the mottling of the target paint film.

Abstract: A portable color sampling device (10) facilitates comparison of a color sampled from an object using an optical sensor (11) with a database (30,42,43,44) of stored colors. The database (30,42,43,44) of stored colors includes a merchandise database of articles for sale, and an indication of the location of those articles, including an indication of some or all of retailer identity, store location, in-store location, article description or product ID, class of article and the like. A user points the color sampling device at an article to be sampled, and a color definition data file is generated for transmission to a database of articles. The database returns to the sampling device a list of merchandise that matches the sampled color or colors and any other matching criteria such as class of article, product code, and geographic proximity.

Abstract: In a multi-angle colorimeter having an illumination system that illuminates a sample surface and a plurality of light receiving systems that receive reflected light therefrom, an illumination system for orientation error detection is provided that illuminates the sample surface from substantially close direction to the normal of the sample surface. Actual measured reflectance factor is corrected based on the specific approximation function obtained from the measured reflectance factor and detected orientation error.

Abstract: In one exemplary embodiment, apparatus is provided with a plurality of laser diodes, sensing means and control means. During normal operation, the laser diodes produce a mixed light. The sensing means measures light that is output by the laser diodes; and the control means 1) compares the measured light to a spectral reference, and 2) sets drive signals of the laser diodes in response to the comparison. In a related and exemplary method, 1) a mixed light is produced using a plurality of laser diodes of different colors, 2) a measurement of light produced by the laser diodes is compared to a spectral reference, and 3) drive signals of the laser diodes are automatically set in response to the comparison.

Abstract: Optical feedback for controlling color of light from a light source is provided. Incident optical energy of the light is detected as a function of discrete steps of wavelength. For each discrete step of wavelength, an X, Y and Z tristimulus subvalue is produced. All the X, Y and Z tristimulus subvalues for all the discrete steps are summed together to produce an X, Y and Z tristimulus value for the light. The X, Y and Z tristimulus values are used as feedback in controlling color of the light generated by the light source.

Abstract: A method for determining the properties of surfaces wherein a first process step specified radiation emits from at least one radiation source to a measuring surface, in further process steps the radiation reflected and/or scattered off the measuring surface is detected by a plurality of image-capturing components, and a signal is generated which specifies at least one parameter of the radiation detected by the image-capturing components. In further process steps the first signals are grouped based on predetermined criteria to form group signals, and at least one group-specific evaluation figure is computed, and a dependent statistical parameter correlating with at least one measuring surface remission characteristic. Finally at least one statistical parameter is read out in dependence on the predetermined criterion for grouping said first signals. The properties of the surface are specified by a relation between at least two statistical parameters.

Abstract: Optical properties of an object are determined via light provided to the object via a probe tip including a plurality of light source/light receiver pairs. Light is received from a first light source/light receiver pair, and the first light source/light receiver pair is arranged so that a first measurement generates data based on light from the object received from a first average optical depth or first thickness sensitivity. Light is received from a second light source/light receiver pair, and the second light source/light receiver pair is arranged so that a second measurement generates data based on light from the object received from a second average optical depth or a second thickness sensitivity. The second average optical depth is different from the first average optical depth. Optical properties of the object are determined based on the data generated by the first and second measurements.

Abstract: A symmetric monitor calibrator for mounting on a cathode ray tube or monitor with a surface. The calibrator has a case that holds electronic and optic components. Suction cups hold the calibrator to the surface, in which the suction cups are attached to the end of supporting elements that surround the case. At least three supporting elements with a common connecting point to form one support structure are connected to the top of the case. The supporting elements extend out creating a greater diameter than the case. The supporting elements and therefore suction cups uniformly surround the center point of the case to prevent rotation caused by the effects of gravity.

Abstract: A method for determining visual calorimetric values for an object having particular spectral reflectance characteristics comprises the steps of: (a) photographing an object with an electronic image capture device to form device image values; (b) selecting a transform from a plurality of transforms for converting device image values to visual colorimetric values, wherein the selection of the transform is based on the particular spectral reflectance characteristics of the object; and (c) applying the selected transform to the device image values to determine the visual colorimetric values for the object.

Abstract: A colorimeter that uses its flexible power/electronic cable as a mounting mechanism is disclosed. The colorimeter can be placed against a target screen, suspended by the cable, where the cable in turn drapes over the top of the display cabinet. A slidable weight can be coupled to the cable to hold a selected position. Alternatively, a slotted suction cup can be used to hold the selected position. A leaf spring can be installed to provide a slight bias force to the backside of the colorimeter, thereby ensuring the colorimeter lays flush to the target screen in the presence of disruptive conditions and anomalies. The colorimeter can further be configured with a low impact suction cup array mount. The colorimeter assembly can be configured with an FOV that corresponds to that of a human, and with self-aligning optical qualities that provide a colorimeter with high SNR.

Abstract: An instrument and related process for measuring color, shade, gloss, shape and/or translucence of a tooth. First, the instrument uses searchlight illumination to illuminate a tooth with constant irradiance. Second, the instrument uses colorimetric imaging to collect time-separated frames of different wavelengths of light reflected from a tooth and to combine those frames into a color image. Third, the instrument includes a sanitary shield to establish a reference color and a predetermined distance to a target tooth. Fourth, the instrument provides line-of-sight viewing so an operator may simultaneously view a display of the image on the instrument and the object being measured. Fifth, the instrument is impervious to pollutants because it incorporates a sealed measurement window. Sixth, optical measurements of a tooth taken by a dentist are compared to optical measurements of a prosthetic restoration for that tooth to confirm satisfactory matching of optical characteristics of the tooth and restoration.

Abstract: A colorimeter device and fabrication techniques are disclosed. The assembly and configuration of the device operates to maximize signal-to-noise ratio, as well as to provide an optimal field of view (e.g., such as an FOV that simulates that of the human eye). Geometric elements and features of the design, in conjunction with the assembly procedure, assure precise alignment of optical elements including sensors, filters, and other elements within the enclosure and optical path.

Abstract: A symmetric monitor calibrator for mounting on a cathode ray tube or monitor with a surface. The calibrator has a case that holds electronic and optic components. Suction cups hold the calibrator to the surface, in which the suction cups are attached to the end of supporting elements that surround the case. At least three supporting elements with a common connecting point to form one support structure are connected to the top of the case. The supporting elements extend out creating a greater diameter than the case. The supporting elements and therefore suction cups uniformly surround the center point of the case to prevent rotation caused by the effects of gravity.

Abstract: A sampling system for performing a spectroscopic analysis on a polymer during its production is described. The system includes a transfer tube capable of transporting the polymer from a production site to a storage site. The tube includes an entry site connected to the production site; and an exit site connected to the storage site. A transparent window is inserted into the wall of the tube, and a door or other barrier is provided to stop the flow of polymer through the tube, so that it accumulates against the window. A spectroscopic device situated outside the tube then takes a reading of the polymer through the window, to perform the desired analysis. Related methods are also described.

Abstract: A spectral distribution error evaluation apparatus is used to evaluate precision of color matching between evaluation and target colors. A first weighting function generator generates a first weighting function on the basis of color matching functions, wavelength characteristics which are independent of a light source of the target color, and visual characteristics which depend on wavelengths. A second weighting function generator generates a second weighting function on the basis of light source information of selected light sources. A difference calculator calculates error values between the evaluation and target colors for respective frequencies. An evaluation value calculator applies the first and second weighting functions to the error values, and calculates the sum total of the error values as an evaluation value.

Abstract: Color/optical characteristics measuring systems and methods are disclosed. Perimeter receiver fiber optics/elements are spaced apart from a central source fiber optic/element and received light reflected from the surface of the object is measured. Light from the perimeter fiber optics pass to a variety of filters. The system utilizes the perimeter receiver fiber optics to determine information regarding the height and angle of the probe with respect to the object being measured. Under processor control, the color measurement may be made at a predetermined height and angle. Various color spectral photometer arrangements are disclosed. Translucency, fluorescence and/or surface texture data also may be obtained. Audio feedback may be provided to guide operator use of the system. The probe may have a removable or shielded tip for contamination prevention.

Abstract: In evaluating whiteness of light from a light source or a luminaire, whiteness W is given by the following equation, W=?5.3C+100, wherein chroma C is determined by the CIE 1997 Interim Color Appearance Model (Simple Version).

Abstract: A method for obtaining an approximate standard color definition for a sample color (2) without the need for standard conditions of illumination or observation. The method comprises using color sensing equipment such as a digital camera (6) to sense under non-standard conditions both the sample color and a plurality of reference colors (5) each being provided on a template (1) and each having a known standard color definition. The sensing under non-standard conditions produces a non-standard color definition both for the sample color and for each of the reference colors.

Abstract: A colorimeter or color measuring device measures color of a sample or an object, and displays measurement value or values according to user defined index or indices, calculated by a user-defined formula. Data of the user-defined formula is read in from outside of the colorimeter and converted into a coded form which can be executed by a controller of the calorimeter. The data of the user-defined formula or the coded data is stored in the colorimeter. Accordingly, the colorimeter has good portability and convenience despite its capability of expressing the colors of various samples or objects by user-defined original index or indices.

Abstract: The invention relates to a method for plain dyeing a textile web of fabric by means of a padding mangle. The squeezing force distribution between the rollers of the padding mangles is controlled according to the dye distribution in the web of fabric which is still provided with the initial humidity on the output of the padding mangle, whereby the dye distribution is measured on certain points by means of a dye measuring appliance. Measuring the dye of the humid web of fabric is simplified and the measured result is improved when a dye receiver is used as the dye measuring device, whereby the receiver separately detects the radiation of a white light source according to pure dyes, the radiation being reflected on the web of fabric in a diffuse manner.

Abstract: The surface contribution to appearance of an object is characterized using a plurality of viewing and illumination angles. The color determining and surface contribution are determined to aid in the predicting of the appearance of an object as well as matching an object to another object.

Abstract: An object of the present invention is to realize to excellently perform a color matching process among media having different white points. To achieve the above object, a colorimetry value of a sample is corrected on a human's color perception space on the basis of a media white point in case of creating transformation data used in transformation performed between data on a color space depending on a device and data on a color space not depending on a device, and the transformation data is created on the basis of the corrected colorimetry value.

Abstract: An instrument and related process for measuring color, shade, gloss, shape and/or translucence of a tooth. First, the instrument uses searchlight illumination to illuminate a tooth with constant irradiance. Second, the instrument uses colorimetric imaging to collect time-separated frames of different wavelengths of light reflected from a tooth and to combine those frames into a color image. Third, the instrument includes a sanitary shield to establish a reference color and a predetermined distance to a target tooth. Fourth, the instrument provides line-of-sight viewing so an operator may simultaneously view a display of the image on the instrument and the object being measured. Fifth, the instrument is impervious to pollutants because it incorporates a sealed measurement window. Sixth, optical measurements of a tooth taken by a dentist are compared to optical measurements of a prosthetic restoration for that tooth to confirm satisfactory matching of optical characteristics of the tooth and restoration.

Abstract: A computer color matching method of paint for measuring a proper formulation of colorants for obtaining a target color or color and luster, or a proper formulation of colorants and luster color materials, directly in a liquid state of paint, without preparing painted panels from adjusted paint, and calculating the adjusted blending ratio easily and accurately, and a paint manufacturing method by using this method.

Abstract: A colorimeter that uses its flexible power/electronic cable as a mounting mechanism is disclosed. The colorimeter can be placed against a target screen, suspended by the cable, where the cable in turn drapes over the top of the display cabinet. A slidable weight can be coupled to the cable to hold a selected position. Alternatively, a slotted suction cup can be used to hold the selected position. A leaf spring can be installed to provide a slight bias force to the backside of the calorimeter, thereby ensuring the colorimeter lays flush to the target screen in the presence of disruptive conditions and anomalies. The calorimeter can further be configured with a low impact suction cup array mount. The colorimeter assembly can be configured with an FOV that corresponds to that of a human, and with self-aligning optical qualities that provide a colorimeter with high SNR.

Abstract: The aim of the invention is to create techniques for the encoding, production and viewing of stereograms, supplemented by methods for selecting certain optical filters needed in these novel techniques, thus providing a human observer with stereograms each of which consist of a single image for viewing through special filter pairs, the stereogram encoding essentially the full color information of the original stereogram or of the original scene, while at the same time encoding the full parallactic depth of the original stereogram or the parallactic depth that would normally be found in a conventional stereogram recorded of the scene. The invention makes use of a color-based encoding technique and viewing filters selected so that the human observer receives, in one eye, an image of nearly full color information, in the other eye, an essentially monochrome image supplying the parallactic differences prescribed by the stereoscopic principle and supplementing the color perception.

Abstract: The indication of correct color evaluation standards of a printed matter including a paper containing a fluorescent whitening agent, is enabled even in the case where the printed matter is observed under a light source that differs from the light source used for color measurement. A spectral reflectance Pt(&lgr;) of the paper under a light source T and a spectral reflectance Pu(&lgr;) of the paper under a light source U are measured in advance and a differential component, due to the fluorescent whitening agent, is determined as Fp(&lgr;)=Pu(&lgr;)−Pt(&lgr;). For a printed matter of dot percent S, a spectral reflectance Rt(&lgr;, S) under light source T is measured, and the measured values are subject to a correction process of adding an effective component within the differential component Fp(&lgr;) that is in accordance to dot percent S to determine an estimated spectral reflectance Rtu(&lgr;, S) under light source U.

Abstract: A method and apparatus allows mutual comparison of a mode of appearance of a color by the visual sense with a mode of appearance of the color from a calorimetric value from a calorimeters, and establishes a corresponding relationship between both evaluations. In the illumination variable calorimetric method and colorimeter, an illumination adjustment mechanism and an illumination measurement light receiver are disposed in a measurement optical path of an optical portion. After an illumination is adjusted to a predetermined illumination while a standard plate is placed on the surface of a sample table, standard adjustment is effected. Thereafter, measurement is started by placing a sample on the sample table, and the illumination of the sample table is varied by the light quantity adjustment mechanism so that changes in hue, saturation and lightness of a surface color of the sample and each color difference value with respect to the change of illumination of the same sample can be measured and displayed.

Abstract: A detector system, filter therefor, and method of making same is disclosed. The filter includes an interference element having a reflection band disposed primarily in the near infrared, and having a high transmission over most of the visible region. The filter also includes an absorptive element that absorbs light non-uniformly over the visible region. The filter when combined with a semiconductor photodiode or other suitable detector yields a detector system whose spectral responsivity closely matches the visual response of the human eye.

Abstract: A spectral distribution error evaluation apparatus is used to evaluate precision of color matching between evaluation and target colors. A first weighting function generator generates a first weighting function on the basis of color matching functions, wavelength characteristics which are independent of a light source of the target color, and visual characteristics which depend on wavelengths. A second weighting function generator generates a second weighting function on the basis of light source information of selected light sources. A difference calculator calculates error values between the evaluation and target colors for respective frequencies. An evaluation value calculator applies the first and second weighting functions to the error values, and calculates the sum total of the error values as an evaluation value.

Abstract: Color/optical characteristics measuring systems and methods are disclosed. Perimeter receiver fiber optics/elements are spaced apart from a central source fiber optic/element and received light reflected from the surface of the object is measured. Light from the perimeter fiber optics pass to a variety of filters. The system utilizes the perimeter receiver fiber optics to determine information regarding the height and angle of the probe with respect to the object being measured. Under processor control, the color measurement may be made at a predetermined height and angle. Various color spectral photometer arrangements are disclosed. Translucency, fluorescence and/or surface texture data also may be obtained. Audio feedback may be provided to guide operator use of the system. The probe may have a removable or shielded tip for contamination prevention.

Abstract: An instrument and related process for measuring color, shade, gloss, shape and/or translucence of a tooth. First, the instrument uses searchlight illumination to illuminate a tooth with constant irradiance. Second, the instrument uses calorimetric imaging to collect time-separated frames of different wavelengths of light reflected from a tooth and to combine those frames into a color image. Third, the instrument includes a sanitary shield to establish a reference color and a predetermined distance to a target tooth. Fourth, the instrument provides line-of-sight viewing so an operator may simultaneously view a display of the image on the instrument and the object being measured. Fifth, the instrument is impervious to pollutants because it incorporates a sealed measurement window. Sixth, optical measurements of a tooth taken by a dentist are compared to optical measurements of a prosthetic restoration for that tooth to confirm satisfactory matching of optical characteristics of the tooth and restoration.

Abstract: In a method of determining the shade stability of paints, the total color difference &Dgr;E(FT) between the color at the film thickness FT and the color at a predetermined film thickness FT0 is measured for different film thicknesses FT. Subsequently, the slope &sgr;(FT) of the plot &Dgr;E(FT) is determined, which represents a useful parameter for the shade stability. Alternatively to &sgr;(FT), it is also possible to determine the limiting film thickness FTlim at which the total color difference &Dgr;E(FT) passes below a predetermined limit. The method of determining the shade stability is additionally employed in order to optimize paint formulations.

Abstract: The present invention relates to a method for the colorimetric measurement of a defined region on an image representing a surface, characterized in that the said image of the said surface is taken using a color camera, in that the analogue information measured on the said surface is transformed and converted into digital form, in that the said defined region on the said image is delimited and in that the measurement of the chromatic values R, G, B is carried out for this region.

Abstract: The invention provides a method of determining tristimulus values for light emitting diode illuminants. A localized transformation matrix is determined based on a set of spectral responsivity data and a set of color-matching functions. A set of color responses associated with light emitted from the light emitting diode illuminants may be measured, and an estimate of tristimulus values based on the localized transformation matrix and the set of color responses may be determined.

Abstract: The invention provides a method of determining tristimulus values for light emitting diode illuminants. A localized transformation matrix is determined based on a set of spectral responsivity data and a set of color-matching functions. A set of color responses associated with light emitted from the light emitting diode illuminants may be measured, and an estimate of tristimulus values based on the localized transformation matrix and the set of color responses may be determined.

Abstract: A method, includes illuminating a first portion of a colored region with first light from a gas discharge tube and generating a first output using a diffuse reflection of the first light from the first portion. The method further includes illuminating a second portion of the colored region with second light from a first solid state lamp and generating a second output using a diffuse reflection of the second light from the second portion. Additionally, the method includes illuminating a third portion of the colored region with third light from a second solid state lamp and generating a third output using a diffuse reflection of the third light from the third portion.

Abstract: A light output control system for implementing a method for sensing the tri-stimulus values for controlling a light output illuminated from an LED based luminary is disclosed. The system comprises one or more filter/photo diode sensors for sensing a first set of tri-stimulus values of the light output and providing signals indicative thereof. The signals are utilized in a transformation matrix whereby a second set of tri-stimulus values is obtained. The system controls the light output as a function of the second set of tri-stimulus values.

Abstract: A method, apparatus and computer-readable medium allows users to measure a lighting condition of an object. In one embodiment, at least one user visually compares colored materials against a displayed color sample. Users may adjust the color of the displayed color sample by changing corresponding attribute values until the displayed color sample appears to substantially match the colored material. Once users indicate that they have established a color match between a displayed color sample and a colored material, the spectral irradiance value of the substantially matched color sample is calculated. The spectral irradiance value represents a measurement of the lighting condition in a particular room.

Abstract: Color/optical characteristics measuring systems and methods are disclosed. Perimeter receiver fiber optics/elements are spaced apart from a central source fiber optic/element and received light reflected from the surface of the object is measured. Light from the perimeter fiber optics pass to a variety of filters. The system utilizes the perimeter receiver fiber optics to determine information regarding the height and angle of the probe with respect to the object being measured. Under processor control, the color measurement may be made at a predetermined height and angle. Various color spectral photometer arrangements are disclosed. Translucency, fluorescence and/or surface texture data also may be obtained. Audio feedback may be provided to guide operator use of the system. The probe may have a removable or shielded tip for contamination prevention.

Abstract: A color reproduction system includes a color conversion unit for displaying a color image on a multi-primary-color display. The color conversion unit includes a maximum brightness signal calculating unit for calculating signals corresponding to three color reproduction area corners as the corners of a plane that constitute a color reproduction area surface of the display. The three color reproduction area corners surround the vectors of input tristimulus values. The maximum brightness signal calculating unit also calculates a weighting factor obtained when the input tristimulus values are expressed as a linear sum of the tristimulus values of the color reproduction area corner vectors. The color conversion unit further includes a color image signal calculating unit for calculating a color image signal used to display the input tristimulus values, on the basis of the signals corresponding to the color reproduction area corners and the weighting factor.