A method for true-to-sample measurement by a mobile ingredient analysis system having a housing with a window, an interface for an external reference unit, a display and operating unit, a light source, an optical spectrometer, a camera, an internal reference unit, and an electronic control unit. The method includes: selecting a calibration product suitable for a sample to be examined; performing a plausibility check of the calibration product, an incorrect selection being signaled and an alternative calibration product being selected; outputting measurement conditions comprising the measurement point to be selected and measurement duration for the selected calibration product; capturing measured values of the sample by the spectrometer under the measurement conditions and with simultaneous monitoring of the measurement conditions; processing the captured measured values by means of an electronic control unit, each measured value captured while the measurement conditions were met being declared valid; outputting the measured values deemed valid.

A device for optical detection of analytes in a sample includes at least two optoelectronic components. The optoelectronic components include at least one optical detector configured to receive a photon and at least one optical emitter configured to emit a photon. The at least one optical emitter includes at least three optical emitters disposed in a flat, non-linear arrangement, and the at least one optical detector includes at least three optical detectors disposed in a flat, non-linear arrangement. The at least three optical emitters and the at least three optical detectors include at least three different wavelength characteristics.

A method of correcting for an amplitude change in a spectrometric instrument output includes: exposing a sample in a sample holder to electromagnetic radiation at a plurality of wavenumbers; detecting electromagnetic absorption intensities in the sample at the plurality of wavenumbers; providing to a computer device the detected electromagnetic absorption intensities indexed against wavenumber as spectral data; applying in the computer device a mathematical transform (Icorr) to the spectral data to correct for an amplitude change in the spectrometric instrument's output and calculated by determining a difference (Δ(SBZ)/) between first derivatives of a logarithmic transformation of spectral data (SB.sub.Z) from the zero material sample at two different wavenumber ranges (log.sub.10(SB.sub.Z(x.sub.1)).sup./ and log.sub.10(SB.sub.Z(x.sub.2)).sup./); and calculating the mathematical transform (Icorr) as a function inversely dependent on the determined difference (Δ(SBZ)/).

A self-calibrating dissolved gas analysis apparatus and associated method are described. The dissolved gas analysis apparatus includes an analyser having an optical absorption measurement system using one or more electromagnetic energy sources to obtain optical absorption measurements associated with a gas sample. An observed response of the optical absorption measurement system is derived at least in part by using the optical absorption measurement system to obtain optical absorption measurements for a reference gas under one or more distinct moisture conditions. The derived observed response is then processed to quantify deviations between the derived observed response and an expected response and the quantified deviations are used to compensate information associated with gas concentration measurements derived by the dissolved gas analysis apparatus.

A device for optical detection of analytes in a sample includes at least two optoelectronic components. The optoelectronic components include at least one optical detector configured to receive a photon and at least one optical emitter configured to emit a photon. The at least one optical emitter includes at least three optical emitters disposed in a flat, non-linear arrangement, and the at least one optical detector includes at least three optical detectors disposed in a flat, non-linear arrangement. The at least three optical emitters and the at least three optical detectors include at least three different wavelength characteristics.

A material evaluating device for an agricultural work machine comprising: a light source for illuminating one or more constituent materials to be examined; a spectrometer for providing a spectral signal related to the wavelength-specific intensity of light reflected by the constituent materials; and an evaluation device configured to determine the content of one or more constituent materials using the spectral signal of the spectrometer and a calibration data, wherein a property signal relating to a property of the one or more constituent materials is supplied to the evaluation device and the evaluation device is configured, using the property signal, to determine the content of the one or more constituent materials.

A self-calibrating dissolved gas analysis apparatus and associated method are described. The dissolved gas analysis apparatus includes an analyser having an optical absorption measurement system using one or more electromagnetic energy sources to obtain optical absorption measurements associated with a gas sample. An observed response of the optical absorption measurement system is derived at least in part by using the optical absorption measurement system to obtain optical absorption measurements for a reference gas under one or more distinct moisture conditions. The derived observed response is then processed to quantify deviations between the derived observed response and an expected response and the quantified deviations are used to compensate information associated with gas concentration measurements derived by the dissolved gas analysis apparatus.

According to one aspect, the present description relates to a stabilized interferometric system comprising a light source (210) for emitting an initial beam (B.sub.0) of coherent light and a spatial light modulator (220) configured to receive at least a first part of said initial beam and input data (203), and configured to emit a spatially modulated beam (B.sub.0m) resulting from a spatial modulation of a parameter of said first part of said initial beam based on said input data. The stabilized interferometric system further comprises a scattering medium (230) configured to receive said spatially modulated beam and a detection unit (240) configured to acquire an interference pattern (IN.sub.0) in a first detection plane (241) at an output of said scattering material, wherein said interference pattern results from the interferences between randomly scattered optical paths taken by the spatially modulated beam through the scattering material. The stabilized interferometric system further comprises a control unit (250) configured to vary the frequency of the laser source in order to at least partially compensate a change in said interference pattern resulting from a change in at least one environmental parameter.

A device for optical detection of analytes in a sample includes at least two optoelectronic components. The optoelectronic components include at least one optical detector configured to receive a photon and at least one optical emitter configured to emit a photon. The at least one optical emitter includes at least three optical emitters disposed in a flat, non-linear arrangement, and the at least one optical detector includes at least three optical detectors disposed in a flat, non-linear arrangement. The at least three optical emitters and the at least three optical detectors include at least three different wavelength characteristics.

Methods, devices, and systems are provided for analyzing the moisture content in natural gas. In one embodiment, a portable moisture analyzer system is provided and can include a moisture analyzer and a housing. The moisture analyzer can include a tunable diode laser absorption spectrometer (TDLAS) and a natural gas sample conditioning system. The TDLAS can be configured to detect water vapor content within a natural gas sample. The sample conditioning system can be in fluid communication with the TDLAS and can be configured to condition at least one of temperature, flow rate, and pressure of a natural gas sample. The housing can be configured to receive the moisture analyzer therein and to protect the moisture analyzer from vibration and/or shock.