The invention relates to an optical system, to a spectrometer device comprising such optical system and to a method to operate such an optical system comprising an entrance aperture for entering primary light containing both a first, lower wavelength range and a second, higher wavelength range into said optical system, a grating for spectral dispersion of the primary light beam into a first fan of diffracted light within the first wavelength range and a primary zero order light beam, a mirror element suitably positioned to reflect the primary zero order light beam back as secondary light beam to the grating where it is dispersed into a second fan of diffracted light within the second wavelength range, a detector arrangement with detectors, an absorber element to be reversibly placed within the primary zero order light beam, and a filter element to be reversibly placed within the primary light beam.

A spectroscopic system may include: a probe having a probe tip and an optical coupler, the optical coupler including an emitting fiber group and first and second receiving fiber groups, each fiber group having a first end and a second end, wherein the first ends of the fiber groups are formed into a bundle and optically exposed through the probe tip; a light source optically coupled to the second end of the emitting fiber group, the light source emitting light in at least a first waveband and a second waveband, the second waveband being different from the first waveband; a first spectrometer optically coupled to the second end of the first receiving fiber group and configured to process light in the first waveband; and a second spectrometer optically coupled to the second end of the second receiving fiber group and configured to process light in the second waveband.

A spectroscopic system may include: a probe having a probe tip and an optical coupler, the optical coupler including an emitting fiber group and first and second receiving fiber groups, each fiber group having a first end and a second end, wherein the first ends of the fiber groups are formed into a bundle and optically exposed through the probe tip; a light source optically coupled to the second end of the emitting fiber group, the light source emitting light in at least a first waveband and a second waveband, the second waveband being different from the first waveband; a first spectrometer optically coupled to the second end of the first receiving fiber group and configured to process light in the first waveband; and a second spectrometer optically coupled to the second end of the second receiving fiber group and configured to process light in the second waveband.

A system for determining a characteristic of a sample includes a light source for directing light into an input of a spectrometer. The spectrometer splits the received light into light outputs each having a different wavelength. An active wavelength selection module (AWSM) includes an optical receiving component (ORC). An actuator is coupled to the spectrometer and/or the ORC to adjust a relative position between the spectrometer and the AWSM so that light is receivable by the ORC from a selected one of the plurality of light outputs. The ORC is configured to direct the received light to a sample. A collector is positioned to collect a portion of light that passes through the sample, and to deliver the collected light to an analysis module. The analysis module is configured to determine a quantity of light transmitted through the sample and to correlate transmitted light with a characteristic of the sample.

A system for determining a characteristic of a sample includes a light source for directing light into an input of a spectrometer. The spectrometer splits the received light into light outputs each having a different wavelength. An active wavelength selection module (AWSM) includes an optical receiving component (ORC). An actuator is coupled to the spectrometer and/or the ORC to adjust a relative position between the spectrometer and the AWSM so that light is receivable by the ORC from a selected one of the plurality of light outputs. The ORC is configured to direct the received light to a sample. A collector is positioned to collect a portion of light that passes through the sample, and to deliver the collected light to an analysis module. The analysis module is configured to determine a quantity of light transmitted through the sample and to correlate transmitted light with a characteristic of the sample.

A device for detecting characteristics of a fluid, with a light source for emitting several light beams, of which one of the light beams is a measurement beam, which is provided for a passage through the fluid, and another light beam is a reference beam, which is provided for bypassing the fluid, with a movable cover device arranged downstream of the light source, which cover device is provided for covering the light beams and which is arranged so as to be transferable between a first position releasing the measurement beam and covering reference beam, and a second position covering the measurement beam and releasing the reference beam, and with a light detector arranged downstream of the cover device.

Diffuse reflectance spectroscopy apparatus for use in analysing a sample comprising a sample receiving location 2 for receiving a sample 3 for analysis; an illumination arrangement 4 for directing light towards a received sample; a detector 6 for detecting light reflected by a received sample; and collection optics 5 for directing light reflected by a received sample towards the detector. The illumination arrangement further comprises an interferometer 42 and a half beam block 45a, 45b which is disposed substantially at a focus in the optical path for blocking light which exits the interferometer, passes said focus, and is reflected from re-entering the interferometer. A half beam block 45a may be disposed in the optical path between the interferometer and the light source 41 for blocking light that exits the interferometer back towards the light source and is reflected by the light source from re-entering the interferometer and/or a half beam block 45b may be disposed in the optical path on the opposite side of the interferometer than the light source.

Diffuse reflectance spectroscopy apparatus for use in analysing a sample comprising a sample receiving location 2 for receiving a sample 3 for analysis; an illumination arrangement 4 for directing light towards a received sample; a detector 6 for detecting light reflected by a received sample; and collection optics 5 for directing light reflected by a received sample towards the detector. The illumination arrangement further comprises an interferometer 42 and a half beam block 45a, 45b which is disposed substantially at a focus in the optical path for blocking light which exits the interferometer, passes said focus, and is reflected from re-entering the interferometer. A half beam block 45a may be disposed in the optical path between the interferometer and the light source 41 for blocking light that exits the interferometer back towards the light source and is reflected by the light source from re-entering the interferometer and/or a half beam block 45b may be disposed in the optical path on the opposite side of the interferometer than the light source.

Aspects of the disclosure relate to a multi-pass gas cell that includes a set of two or more reflectors, an input collimating optical component, and an output focusing optical component. The input and output optical components are integrated with at least one of the two or more reflectors. For example, the input and output optical components may be integrated on opposite ends of a single one of the reflectors or may be integrated on the same end of a single reflector. The input and output optical components may further be integrated with different reflectors. In some examples, the set of reflectors and optical components may be fabricated within the same substrate.

Aspects of the disclosure relate to a multi-pass gas cell that includes a set of two or more reflectors, an input collimating optical component, and an output focusing optical component. The input and output optical components are integrated with at least one of the two or more reflectors. For example, the input and output optical components may be integrated on opposite ends of a single one of the reflectors or may be integrated on the same end of a single reflector. The input and output optical components may further be integrated with different reflectors. In some examples, the set of reflectors and optical components may be fabricated within the same substrate.