Abstract: A color measuring device includes a lighting arrangement for a measurement field of a measurement object to be measured, a pick-up arrangement for detecting the measurement light reflected back from the measurement field and for converting it into corresponding electric signals, an electronic circuit for controlling operation of the color measuring device and for processing and evaluating the electric signals, and a display for displaying measurement results. The lighting arrangement has a lamp ring with three identical lamp groups for illuminating the measurement field from a predefined range of angles of incidence. The pick-up arrangement has a digital camera which creates an image of the measured measurement field. The electronic circuit is designed to switch the light sources of the lamp groups on sequentially, and the camera creates a separate image of the measurement field for every switched-on light source.

Abstract: A hand-held color measurement device is provided that includes a housing with a measurement unit which receives measurement light through a measurement window, converts it into measurement signals, processes the measurement signals to form digital color measurement data, and provides it via a communications interface. A U-shaped bracket is arranged on the housing and includes a middle portion in which a diffuser is integrated. The two side arms of the bracket are rotatably mounted on the housing such that the bracket can be pivoted by 180° from a monitor position to an ambient light position and back to the monitor position, and wherein the diffuser lies in front of the measurement window in the ambient light position and is situated at a rear wall of the housing opposite the front wall in the monitor position. A holding mechanism is provided on the housing and on the two side arms of the bracket which fixes the bracket in its monitor position or ambient light position, respectively.

Abstract: In a calibrating method for a filter color measuring device that includes at least three color channels, a calibration matrix for transforming output signals of the color channels into tristimulus color values is formed. The calibration is performed spectrally, wherein the spectral sensitivities of the color channels of the color measuring device and the spectral emission properties of typical light sources are measured and stored, and the calibration matrix is calculated from the spectral sensitivities and the spectral emission properties of the light sources and the spectral evaluation functions of the standard observer, e.g., according to CIE 1931.

Abstract: A hand-held color measurement device is provided that includes a housing with a measurement unit which receives measurement light through a measurement window, converts it into measurement signals, processes the measurement signals to form digital color measurement data, and provides it via a communications interface. A U-shaped bracket is arranged on the housing and includes a middle portion in which a diffuser is integrated. The two side arms of the bracket are rotatably mounted on the housing such that the bracket can be pivoted by 180° from a monitor position to an ambient light position and back to the monitor position, and wherein the diffuser lies in front of the measurement window in the ambient light position and is situated at a rear wall of the housing opposite the front wall in the monitor position. A holding mechanism is provided on the housing and on the two side arms of the bracket which fixes the bracket in its monitor position or ambient light position, respectively.

Abstract: A hand-held color measurement device is provided that includes a housing with an opto-measurement unit. The latter includes an optics array for receiving measurement light and a sensor array which is exposed to the measurement light, converts the measurement light into electrical measurement signals, and processes them to form digital measurement data. The measurement unit (M) consists of an aspherical input lens (L1), an aperture (B) for limiting the incident angular range, a depolarizing diffuser (D), a sensor lens (L2) and at least three sensors (S1, 52, S3) which are sensitized to different spectral ranges using color filters (F1, F2, F3). The aperture (B) lies substantially in the focal plane of the input lens (L1), and the diffuser (D) is arranged in the immediate vicinity of the aperture (B) and in the focal plane of the sensor lens (L2). The filters (F1, F2, F3) and the sensors (S1, S2, S3) are arranged close to the optical axis (A) and exposed to substantially parallel measurement light.

Abstract: A hand-held light measuring device includes a device housing (G) with a bottom face incorporating a measuring window (7) through which a measurement optical path extends so that a measurement object can be measured when the device housing (G) is positioned with its bottom face on the measurement object. The measuring device has an integrated, displaceably mounted white reference tile, which can be moved into the measurement optical path and moved back out of it again. The white reference tile is disposed in an end region of an oblong support plate (10) on its side directed towards the housing interior.

Abstract: A color measuring device includes a lighting arrangement (10) for a measurement field (MF) of a measurement object (MO) to be measured, a pick-up arrangement (20) for detecting the measurement light reflected back from the measurement field and for converting it into corresponding electric signals, an electronic circuit (200) for controlling operation of the color measuring device and for processing and evaluating the electric signals, and a display (D) for displaying measurement results. The lighting arrangement (10) has a lamp ring (11) with three identical lamp groups (L1, L2, L3), mutually offset an angle of preferably 120°, each with, for example, 10 light sources (Ln) with different radiation characteristics in the form of light-emitting diodes for illuminating the measurement field (MF) from a predefined range of angles of incidence. The pick-up arrangement (20) has a digital camera (22) which creates an image of the measured measurement field (MF) made up of image pixels.

Abstract: A hand-held light measuring device includes a device housing (G) with a bottom face incorporating a measuring window (7) through which a measurement optical path extends so that a measurement object can be measured when the device housing (G) is positioned with its bottom face on the measurement object. The measuring device has an integrated, displaceably mounted white reference tile, which can be moved into the measurement optical path and moved back out of it again. The white reference tile is disposed in an end region of an oblong support plate (10) on its side directed towards the housing interior.

Abstract: Methods for measuring the colour of printed samples by measuring a first spectral proportion of the total spectral reflection factor of a sample by illuminating the sample with light having no UV element are provided. The methods calculate a spectral correction factor by making allowance for the characterisation data of the brightened substrate and the spectral properties of a selected type of illuminating light, adding the spectral correction factor to the first spectral proportion to obtain the total spectral reflection factor of the measured sample. The methods further evaluate the total spectral reflection factor on the basis of measurements taken with illuminating light with no UV element and with UV light only on a limited set of measurement samples, especially on the non-printed substrate only (paper whiteness).

Abstract: A handheld color measurement device includes a housing in which an optoelectronic measurement unit is located which receives measurement light originating from a measurement object, converts it into corresponding electrical measurement signals and processes these measurement signals into preferably digital measurement data characterizing the color of the measurement object. It further includes passive components required for the realization of different application functions, such as measurement windows and reference standards, which can be selectively positioned into the measurement beam path of the measurement unit. The passive components are positioned in a first housing block (100) and the opto-electronic measurement unit as a whole in a second housing block (200).

Abstract: The measuring device comprises a lighting system, a photoelectric receiver unit and optical means. The lighting system applies light to image elements disposed in strip-shaped lighting regions (15) at a standardized angle of incidence range. The photoelectric receiver unit comprises several photoelectric line sensors (21) disposed parallel at a distance apart which are sensitized to different wavelength ranges by color filters (22) connected upstream. The optical means comprise linear optical arrays (31) which pick up the measurement light reflected by the image elements at a standardized range of angle of reflection and direct it to one of the respective line sensors (21). By means of optical screening and other structural features, cross-talk effects between adjacent image elements are largely reduced.

Abstract: A spectrophotometer for integration purposes includes a measurement head with an illumination arrangement (10) including at least one fight source (11) for the illumination of a measurement object located in a measurement plane (M) under an angle of incidence of at least 45°, with a pick-up arrangement for capturing the measurement light remitted by the measurement object under an angle of reflection of the essentially 0° relative to the perpendicular of the measurement plane, a spectrometer arrangement (30) with an entry slot (31) for the spectral splitting of the measurement fight received through the entry slot and captured and with a photoelectric receiver arrangement (32) exposed to the spectrally split measurement light for conversion of the individual spectral portions of the measurement light into corresponding electrical signals.

Abstract: A color measurement device includes a color measurement channel (20,30) and a control (C), which forms color measurement values from the measurement signals of the color measurement channel and from stored white calibration data. It further includes correction means in order to calculate or correct the color measurement values depending on different distances (a) and/or angles (?) to the measurement object. Because of the special measurement value correction, the color measurement device is especially suited for contactless measurement applications with variable distances and angle orientations relative to the measurement object.

Abstract: A scanning device for photoelectrically measuring a measurement object in the form of a printed sheet on the basis of image elements comprises a measuring table (MT) for supporting the measurement object, a measuring device which can be moved above the surface of the measuring tables for scanning image element lines of the measurement object, a drive system for moving the measuring device above the measurement object, a measurement and drive control system for the measuring device and drive system, and a processing unit, for processing and evaluating the measurement signals generated by the measuring device from the scanned image elements of the measurement object (S). The measuring device comprises a lighting system, a photoelectric receiver unit and optical means. The lighting system applies light to image elements disposed in strip-shaped lighting regions (15) at a standardized angle of incidence range.

Abstract: To measure the colour of samples printed on a substrate containing brightener, a first spectral proportion of the total spectral reflection factor of the sample is measured by illuminating the sample with light having no UV element. From this first spectral proportion, a spectral correction factor is calculated making allowance for the characterisation data of the brightened substrate and the spectral properties of a selected type of illuminating light. The spectral correction factor is added to the first spectral proportion in order to obtain the total spectral reflection factor of the measured sample. The total spectral reflection factor is then evaluated for measuring and control purposes, in particular for calculating colour values of the sample. The characterising data of the substrate is determined on the basis of measurements taken with illuminating light with no UV element and with UV light only on a limited set of measurement samples, especially on the non-printed substrate only (paper whiteness).

Abstract: For the color measurement of samples printed on a substrate including a brightener, a raw spectral reflection factor of the sample is measured in a first measurement by illumination of the sample with light without UV portion. In a second measurement, a fluorescence spectrum of the sample is measured by illumination of the sample with only UV light. The measured fluorescence spectrum is recalculated as a corrected fluorescence spectrum by weighting with spectrally dependent correction factors and, finally, the measured raw spectral reflection factor and the corrected fluorescence spectrum are added to form a corrected spectral reflection factor from which the values characterizing the color of the sample are then calculated. The spectral correction factors are determined during the device manufacture for a certain set of light types and stored in the device.

Abstract: An illumination arrangement for a color measurement device includes a linear arrangement of light emitting diode chips (11) packed tightly along a narrowly defined path. A plurality of light emitting diode chips within at least one region of the path emit light of substantially the same color and are directly covered together with a resin in which a converter material is included for the conversion of the light emitted by the light emitting diode chips of the plurality thereof into at least one other wavelength range. An illumination light with cosine characteristic is emitted from a surface of the resin. UV light emitting regions and non-UV light emitting regions as well as regions including color filters and/or polarization filters may be provided. The illumination arrangement may include white emitting regions and narrow band emitting regions constructed especially for color density measurement.

Abstract: A spectral photometer intended for integration purposes includes a measurement head equipped with illumination arrangement including at least one light source for the illumination at an angle of incidence of 45° of a measured object and located in a measurement plane, a pickup arrangement for capturing the measurement light remitted by the measured object at an angle of reflection of essentially 0° relative to the perpendicular to the measurement plane, a spectrometer arrangement including an entry aperture for the spectral splitting of the measurement light captured and fed through the entry aperture, and a photoelectric receiver arrangement exposed to the split measurement light for conversion of the individual spectral components of the measurement light into corresponding electrical signals. It further includes an electronic circuit for control of the light source and forming digital measurement values from the electrical signals produced by the photoelectric receiver arrangement.

Abstract: A photoelectric color measuring head for measuring color properties of a measurement object includes an illumination device for exposing the measurement object to illuminating light and a wavelength-range-selective photoelectric receiver device (40) which intercepts measurement light remitted by the illuminated measurement object and converts it into corresponding electrical measurement signals. The illumination device includes an essentially white light-emitting diode (30) and means (60) for defining the angle of incidence range, so that the measurement object receives light only within an angle of incidence range, standardized for color measurement applications, of preferably 45°+/?5-10°. The receiver device includes a sensor field consisting of a multitude of photoelectric sensor pixels arranged in a line and the sensor pixels are made sensitive to different wavelength ranges through previously arranged color filters (420).

Abstract: A handheld colour measurement device includes a housing in which an optoelectronic measurement unit is located which receives measurement light originating from a measurement object, converts it into corresponding electrical measurement signals and processes these measurement signals into preferably digital measurement data characterizing the colour of the measurement object. It further includes passive components required for the realization of different application functions, such as measurement windows and reference standards, which can be selectively positioned into the measurement beam path of the measurement unit. The passive components are positioned in a first housing block (100) and the opto-electronic measurement unit as a whole in a second housing block (200).