An apparatus for determining a colour of a translucent material. The apparatus comprises a first light source configured to illuminate a translucent material at a first surface location, a second light source configured to illuminate the translucent material at a second surface location spaced apart from said first surface location, and a light spectral sensor configured to detect light at said first surface location. The apparatus is configured to operate the first and second light sources alternately, and such that light detected by the light spectral sensor originating from said first source is principally light diffusely reflected from said first surface location, whilst light detected by the detector originating from said second source is principally light scattered by scattering centres in the interior of the translucent material.

An apparatus for determining a colour of a translucent material. The apparatus comprises a first light source configured to illuminate a translucent material at a first surface location, a second light source configured to illuminate the translucent material at a second surface location spaced apart from said first surface location, and a light spectral sensor configured to detect light at said first surface location. The apparatus is configured to operate the first and second light sources alternately, and such that light detected by the light spectral sensor originating from said first source is principally light diffusely reflected from said first surface location, whilst light detected by the detector originating from said second source is principally light scattered by scattering centres in the interior of the translucent material.

Method for providing a natural colour and optical depth to a dental object comprising the steps: providing a framework of the dental object, taking an object colour picture of an adjacent dental object or reference dental object, and uploading the object colour picture into a computing device, calibrating and adjusting the uploaded object colour picture into a target object colour picture in a computing device, (pre)determining the thickness profile of the enamel material to be applied on the framework, correcting in a computing device of the digital picture elements of the target object colour picture for the thickness profile of the enamel material to be applied on the position of the digital picture elements and providing a print colour picture of the corrected digital picture elements, printing the print colour picture as a print layer on the framework, applying the enamel material in the predetermined profile-thickness upon the print layer upon the framework.

A cradle can be used to capture video of an object, such as hair. That video can then be used to extract and visualize color information relating to that material using a colorcloud. The colorcloud contains all the colors that were present in one or more frames of the video. The cradle comprises a video recording device that is able to see the material through a window on the cradle. A smartphone can be used with the cradle to act as the video recording device, as well as provide lighting.

An optical milk measuring arrangement operative during a milking operation, and including an optical measuring device for measuring optical properties of milk in a measuring region, in which at least part of the milk fed to the measuring arrangement collects. The measuring arrangement includes a main channel and a measuring channel, and these channels are in fluid communication with one another in a region of a common inlet and a common outlet, and the measuring channel has a lower flow velocity than a flow velocity in the main channel.

An illumination device and method are provided herein for calibrating individual LEDs in the illumination device to obtain a desired luminous flux and a desired chromaticity of the device over changes in drive current, temperature, and over time as the LEDs age. The calibration method may include subjecting the illumination device to a first ambient temperature, successively applying at least three different drive currents to a first LED to produce illumination at three or more different levels of brightness, obtaining a plurality of optical measurements from the illumination produced by the first LED at each of the at least three different drive currents, obtaining a plurality of electrical measurements from the photodetector and storing results of the obtaining steps within the illumination device to calibrate the first LED at the first ambient temperature. The plurality of optical measurements may generally include luminous flux and chromaticity, the plurality of electrical measurements may generally include induced photocurrents and forward voltages, and the calibration method steps may be repeated for each LED included within the illumination device and upon subjecting the illumination device to a second ambient temperature.

Described herein is a method for generating a bi-directional texture function (BTF) of an object, the method including at least the following steps: measuring an initial BTF for the object using a camera-based measurement device, capturing spectral reflectance data for the object for a pre-given number of different measurement geometries using a spectrophotometer, and adapting the initial BTF to the captured spectral reflectance data), thus, gaining an optimized BTF.

Also described herein are respective systems for generating a bi-directional texture function of an object.

Disclosed are an apparatus, a system, and a control method for measuring an LED panel. The method for measuring an LED panel comprises the steps of: capturing an image of an LED panel displayed in a preset color; classifying each pixel of the LED panel from the captured image of the LED panel into pixel regions having different sizes according to a predetermined threshold brightness value; obtaining a tristimulus value of each pixel by using the data of the classified pixel regions and a trained artificial intelligence model; and obtaining the luminance and chrominance of each pixel on the basis of the obtained tristimulus value.

Automation of the comparison of the colors of small surfaces of products. In one embodiment, color differences are measured rather than an absolute color value. An apparatus is provided for capturing color images of a portion of a product or part to provide a sample product image. The sample image is compared to an image of a standard product obtained under the same conditions with the same apparatus. The color difference is measured to determine when it is in a predetermined range.

An illumination device comprises one or more emitter modules having improved thermal and electrical characteristics. According to one embodiment, each emitter module comprises a plurality of light emitting diodes (LEDs) configured for producing illumination for the illumination device, one or more photodetectors configured for detecting the illumination produced by the plurality of LEDs, a substrate upon which the plurality of LEDs and the one or more photodetectors are mounted, wherein the substrate is configured to provide a relatively high thermal impedance in the lateral direction, and a relatively low thermal impedance in the vertical direction, and a primary optics structure coupled to the substrate for encapsulating the plurality of LEDs and the one or more photodetectors within the primary optics structure.