A device for radiometrically gauging the surface of a measurement object (O) includes: at least one measurement array featuring an illumination array and a pick-up array; and a processor (P) for controlling the illumination array and the pick-up array and for processing measurement signals produced by the pick-up array and for providing processed image data. The illumination array exposes a region of the measurement object (O) to illumination light at an illumination angle (.sub.i) and an illumination aperture angle (.sub.i), and the pick-up array captures measurement light, reflected by the measurement object (O), at a pick-up angle (.sub.v) and a pick-up aperture angle (.sub.v) and guides it onto an image sensor exhibiting a pixel structure. The measurement object (O) is gauged multispectrally in multiple wavelength ranges, wherein the image sensor produces multispectral image data. Angular and spatial conditions are indicated which optimise the measurement device (MD) with regard to characterising sparkles.

A sensor arrangement for determining a concentration of a substance in an open sample in the presence of an interfering material is disclosed. The sensor arrangement comprises a first light source emitting pulsed light at a first wavelength being absorbed by said substance, a second light source emitting pulsed light at a second wavelength being transmitted through said substance, optical means for directing at least a part of the emitted pulsed light of said first and second wavelengths through the open sample along the same optical path, and a sample detector arranged at an end of the optical path for receiving the emitted light of said first and second wavelengths being transmitted through the sample. The interfering material is formed as deposits on at least one of said optical means being exposed to said substance, and said first wavelength and said second wavelength are absorbed by said interfering material.

An apparatus (100) for optically characterizing a textile sample (106) comprises a presentation subsystem (102) comprising a viewing window (108). A radiation subsystem (114) comprises a radiation source (120) for directing a first, ultraviolet radiation (122) and a second, visible radiation (123) toward the sample (106), and causing the sample (106) to produce a fluorescent radiation (124) and a reflected radiation (125). A sensing subsystem (126) comprises an imager (130) for capturing the fluorescent radiation (124) and the reflected radiation (125) in an array of pixels (408). A control subsystem (132) comprises a processor (136) for controlling the presentation subsystem (102), the radiation subsystem (114), and the sensing subsystem (126), and for creating a fluorescent and reflected radiation image (400) containing both spectral information and spatial information in regard to the fluorescent radiation (124) and the reflected radiation (125).

A spectrometer includes a light source and a digital micromirror device (DMD) that splits light from the light source to control an intensity of light directed at a sample. The intensity of the light may be controlled in order to smooth an intensity of light through a sample without analyte based on differential wavelength absorption. Alternatively, the intensity of light may be modulated in conjunction with an out-of-phase reference beam to create a simplified double-beam spectrometer with a single light source and a single detector.

A water quality measurement device for measuring water quality, the water quality measuring device comprising: a white light emitting element configured to emit substantially white light, an infra-red light emitting element configured to emit substantially infra-red light, and a light receiving element configured to receive and detect light from the white light emitting element and the infra-red light emitting element; wherein, the white light emitting element is arranged co-axial and opposite the light receiving element, and wherein the emission axis of the infra-red emitting element is arranged substantially orthogonal the incident axis of the light receiving element.