Abstract: A laser absorption spectrometry system for gas measurement is provided. The system includes an integrated cavity output spectroscopy (ICOS) assembly. The assembly includes a gas cell including a cell body defining an optical cavity, one or more tunable diode lasers having one or more nominal wavelengths, and a reflective collimation mirror positioned in an optical path between the one or more tunable diode lasers and the gas cell.

Abstract: The present disclosure relates to systems and methods that include a multiple pump manifold to provide redundancy for use with high availability gas extraction system in industrial instrumentation. A method of operating a redundant pump assembly including operating a first pump of a plurality of pumps for an operation period; validating a second pump of the plurality of pumps at the end of the operation period of the first pump; validating a third pump of the plurality of pumps at the end of the operation period of the first pump; and, operating the third pump for the operation period, where the second pump and third pump are validated as operational.

Abstract: The present disclosure relates to measuring chemical constituents and associated properties of hydrocarbon fuel mixtures, and further relates to tunable diode laser absorption spectrometry gas analyzers having improved chemometric models.

Abstract: A laser absorption spectrometry system for gas measurement is provided. The system includes an integrated cavity output spectroscopy (ICOS) assembly including a gas cell. The gas cell includes a cell body defining an optical cavity and an input mirror and an output mirror positioned in the optical cavity. The assembly further includes a tunable diode laser configured to emit laser light, a collimator positioned in an optical path between the tunable diode laser and the gas cell, and a detector arranged to measure laser light exiting the optical cavity. The collimator includes at least one of a reflective collimation mirror or a gradient index (GRN) lens.

Abstract: A method for spectral interpretation in absorption spectroscopy uses a nonlinear spectral fitting algorithm for interpretation of spectral features in complex absorption spectra. The algorithm combines two spectral modeling techniques for generating spectral models to be used in the curve fitting process: a line-shape model and a basis-set model. The selected models for all gas components are additively combined using a least squares minimization, allowing for quantification of multiple species simultaneously.

Abstract: A cavity-enhanced absorption spectroscopy instrument has an optical cavity with two or more cavity mirrors, one mirror of which having a hole or other aperture for injecting a light beam, and the same or another mirror of which being partially transmissive to allow exit of light to a detector. A spherical-spherical configuration with at least one astigmatic mirror or a spherical-cylindrical configuration where the spherical mirror could also be astigmatic prevents a reentrant condition wherein the injected beam would prematurely exit the cavity through the aperture. This combination substantially increases the number of passes of the injected beam through a sample volume for sensitive detection of chemical species even in less than ideal conditions including low power laser or LED sources, poor mirror reflectivity or detector noise at the wavelengths of interest, or cavity alignment issues such as vibration or temperature and pressure changes.

Abstract: A cavity-enhanced absorption spectroscopy instrument has an optical cavity with two or more cavity mirrors, one mirror of which having a hole or other aperture for injecting a light beam, and the same or another mirror of which being partially transmissive to allow exit of light to a detector. A spherical-spherical configuration with at least one astigmatic mirror or a spherical-cylindrical configuration where the spherical mirror could also be astigmatic prevents a reentrant condition wherein the injected beam would prematurely exit the cavity through the aperture. This combination substantially increases the number of passes of the injected beam through a sample volume for sensitive detection of chemical species even in less than ideal conditions including low power laser or LED sources, poor mirror reflectivity or detector noise at the wavelengths of interest, or cavity alignment issues such as vibration or temperature and pressure changes.

Abstract: A method for spectral interpretation in absorption spectroscopy uses a nonlinear spectral fitting algorithm for interpretation of spectral features in complex absorption spectra. The algorithm combines two spectral modeling techniques for generating spectral models to be used in the curve fitting process: a line-shape model and a basis-set model. The selected models for all gas components are additively combined using a least squares minimization, allowing for quantification of multiple species simultaneously.