Disclosed herein is a dust measuring apparatus and method for measuring a dust concentration in a flow channel. The apparatus includes a flow channel unit for defining a flow channel allowing a fluid containing dust to move therethrough, a light emitter for emitting light into the flow channel, a light detector for detecting light scattered from the dust in the flow channel and converting it to an electrical detection signal, the light detector including a plurality of detectors having different light detection ranges, and a controller for controlling the flow channel unit, the light emitter and the light detector, wherein the controller is configured to receive detection signals from the detectors, compensate for an offset for the received detection signals, and measure a dust concentration based on the compensated detection signals.

A method for a wearable device to determine a biological parameter of a tissue of a person. To apply an emitting of a first and a second wavelength of light towards the tissue. To collect and sense a first and a second set of frequency bands from the signals received back from the first and the second wavelengths respectively. The first set of frequency bands represents a first signal which corresponds to a combination of the biological parameter and an extraneous noise. The second set of frequency bands represents a second signal mainly comprising the extraneous noise. To subtract the first set of frequency bands from the second set of frequency bands in the frequency domain to obtain a third set of frequency bands. The third set of frequency bands represents a third signal corresponding to the biological parameter.

An electronic apparatus includes an output interface and a controller. The output interface is configured to output a signal on the basis of scattered light from a measured part. The controller is configured to calculate a temporal change of a power spectrum on the basis of the signal and detect noise included in the signal on the basis of the temporal change of the power spectrum.

An optical measurement device includes an irradiation optical system, a detection optical system, and a cancel circuit. In a fluorescence detection process, a sample is designated as an irradiation target, the sample is irradiated with irradiation light, measurement target light including fluorescence generated from the sample irradiated with the irradiation light and light scattered from the sample irradiated with the irradiation light is detected as detection light, a signal component corresponding to the scattered light is removed from a measurement signal corresponding to the measurement target light in consideration of a result of performing a calibration process during a preliminary process. In the preliminary process, the calibration process for removing a signal component corresponding to the scattered light from the measurement signal is performed on the basis of a calibration signal having a higher signal intensity than a signal corresponding to the scattered light in the measurement signal.

In an optical measurement device, in a first process, a reference member is irradiated with excitation light, light for a calibration process including scattered light associated with the excitation light from a reference member is detected as detection light, a calibration signal corresponding to the light for the calibration process is designated as a detection signal, and a calibration process for removing a signal component corresponding to the scattered light from the detection signal in a second process is performed. Also, in the optical measurement device, in the second process, a sample is irradiated with the excitation light, measurement target light including fluorescence generated from the sample and light scattered from the sample irradiated with the excitation light is detected as detection light, and a signal component corresponding to the scattered light from a measurement signal.

A nephelometric turbidimeter for measuring a turbidity of a liquid sample in a sample cuvette. The nephelometric turbidimeter includes a measurement light source configured to emit an axial parallel light beam directed to the sample cuvette, a scattering light detector arranged to receive a scattered light from the sample cuvette, and a diffuser comprising a diffuser body and a diffuser actuator. The diffuser actuator is configured to move the diffuser body between a parking position in which the diffuser body does not interfere with the axial parallel light beam and a test position where the diffuser body is arranged between the measurement light source and the sample cuvette so that the diffuser body interferes with the axial parallel light beam and generates a diffuse test light entering the sample cuvette.

According to various, but not necessarily all, embodiments there is provided an apparatus comprising means for: capturing or causing capture of an image of an object using a rolling shutter having an aperture width and shutter scan speed; during the image capture, projecting or causing projection of electromagnetic radiation with a fixed-spatial, time-variable distribution onto the object, wherein the time-variable distribution of the projected electromagnetic radiation, the aperture width of the rolling shutter, and the shutter scan speed of the rolling shutter, are such that adjustment of one or more of these would not decrease a proportion of projected electromagnetic radiation captured which is directly reflected from a surface of the object.

A method for a wearable device to determine a biological parameter of a tissue of a person. To apply an emitting of a first and a second wavelength of light towards the tissue. To collect and sense a first and a second set of frequency bands from the signals received back from the first and the second wavelengths, respectively. The first set of frequency bands represents a first signal which corresponds to a combination of the biological parameter and an extraneous noise. The second set of frequency bands represents a second signal mainly comprising the extraneous noise. To subtract the first set of frequency bands from the second set of frequency bands in the frequency domain to obtain a third set of frequency bands. The third set of frequency bands represents a third signal corresponding to the biological parameter.

According to various, but not necessarily all, embodiments there is provided an apparatus comprising means for: capturing or causing capture of an image of an object using a rolling shutter having an aperture width and shutter scan speed; during the image capture, projecting or causing projection of electromagnetic radiation with a fixed-spatial, time-variable distribution onto the object, wherein the time-variable distribution of the projected electromagnetic radiation, the aperture width of the rolling shutter, and the shutter scan speed of the rolling shutter, are such that adjustment of one or more of these would not decrease a proportion of projected electromagnetic radiation captured which is directly reflected from a surface of the object.

Described herein is a process for correcting an observed color difference between a color at a first gloss and the color at a second gloss different than the first gloss, said process comprising the steps of: (a) determining a first correction caused by a lightness (Y-value) of the color a first gloss; (b) determining a second correction caused by an inclusion of a first surface diffusion in gloss readings; (c) based on the first and second corrections, determining a specular correction caused by a difference in specular reflections from the color at the first gloss and the color at the second gloss; (d) determining tristimulus corrections based on the specular correction; (e) preparing corrected tristimulus values of the color at a second gloss; and (f) producing a paint composition for the color at the second gloss using the corrected tristimulus values.