Spectrometers include an optical assembly with optical elements arranged to receive light from a light source and direct the light along a light path to a multi-element detector, dispersing light of different wavelengths to different spatial locations on the multi-element detector. The optical assembly includes: (i) a collimator arranged in the light path to receive the light from the light source, the collimator including a mirror having a freeform surface; (2) a dispersive sub-assembly including an echelle grating, the dispersive sub-assembly being arranged in the light path to receive light from the collimator; and (3) a Schmidt telescope arranged in the light path to receive light from the dispersive sub-assembly and focus the light to a field, the multi-element detector being arranged at the field.

An echelle spectrometer includes a slit opening for incoming light, a collimator which collimates a diverging beam of light generated through the slit, a reflective echelle grating which disperses the collimated light along a first dimension; a cross-disperser which disperses at least a portion of the collimated light in a second dimension orthogonal to the first dimension to create a two-dimensional spectral field-of-view; and an imaging system which images the two- dimensional spectral field-of-view onto a detector; wherein the imaging system comprises primary, secondary, and tertiary tilted mirrors, where each of the tilted mirrors comprises a freeform, rotationally non-symmetric surface shape.

A two-dimensional spectrometer includes a first mirror, a prism, a diffraction grating, a lens, a second mirror, and a two-dimensional sensor. The first mirror is configured to receive the optical signal from the optical entrance and reflect the optical signal towards the prism. After passing through the prism, the optical signal is provided to the diffraction grating. The diffraction grating diffracts the optical signal so as to generate a diffracted optical signal which is directed back through to prism, wherein the lens configured focuses the diffracted optical signal onto the second mirror. The second mirror reflects the diffracted optical signal back through the lens which focuses the diffracted optical signal onto the two-dimensional sensor. The diffraction grating may be an echelle grating.

A LIBS system to detect constituent elements of interest within a sample from plasma light resulting from irradiation of this sample is presented. The LIBS system has a hybrid configuration which provides both a low-resolution spectrum of the plasma light covering a broad spectral range, and a high-resolution spectrum of the same plasma light over a narrow spectral range centered on a spectral line or feature of a constituent element of interest of the sample. In some implementations, the LIBS system has a portable design and can perform onsite sample analyses.

A system for non-invasively interrogating an in vivo sample for measurement of analytes comprises a pulse sensor coupled to the in vivo sample for detect a blood pulse of the sample and for generating a corresponding pulse signal, a laser generator for generating a laser radiation having a wavelength, power and diameter, the laser radiation being directed toward the sample to elicit Raman signals, a laser controller adapted to activate the laser generator, a spectrometer situated to receive the Raman signals and to generate analyte spectral data; and a computing device coupled to the pulse sensor, laser controller and spectrometer which is adapted to correlate the spectral data with the pulse signal based on timing data received from the laser controller in order to isolate spectral components from analytes within the blood of the sample from spectral components from analytes arising from non-blood components of the sample.

This disclosure is related to devices, systems, and techniques for precisely measuring a wavelength of an optical signal. For example, a wavemeter system includes processing circuitry, a detector array, a set of optical chips, and a coarse wavelength unit configured to generate a coarse wavelength measurement of the input optical signal. The processing circuitry is configured to select an optical chip from a plurality of optical chips. The detector array is configured to generate a partial interferogram based on the at least the portion of the input optical signal. The processing circuitry is further configured to calculate an optical spectrum of the input optical signal based on the partial interferogram corresponding to the at least the portion of the input optical signal and the calibration matrix and identify, based on the optical spectrum of the input optical signal, the precise wavelength of the input optical signal.

Certain configurations are described herein of an optical spectrometer and instruments including an optical spectrometer. In some instances, the optical spectrometer is configured to spatially separate provided wavelengths of light to permit detection or imaging of each provided wavelength of light. Improved sensitivities and detection limits may be achieved using the optical spectrometers described herein.

Certain aspects, configurations, embodiments, and examples of a spectrometer with a compact design are described. In some implementations, the spectrometers according to the present disclosure may be used for optical emission spectroscopy (OES). The spectrometer architecture and imager described herein allows a single detector, compact, and high-throughput spectrometer. One or more aspects include an Echelle grating in a spectrometer that reuses optical surfaces to separate wavelengths of light. For example, in one or more aspects, a reflective triplet telescope acts as both a collimator and imager. By reusing optical components, the relative size of the spectrometer may be reduced.

The present disclosure relates to a spectrometer arrangement for analyzing optical radiation from a light source comprising an echelle grating for dispersion of the radiation entering the spectrometer arrangement in a main dispersion direction, a dispersion element for dispersing the radiation in a cross-dispersion direction, the main dispersion direction and the cross-dispersion direction having a predeterminable angle to each other, and a detector unit for acquiring a first spectrum of a first part of the radiation comprising a first predeterminable wavelength range. According to the present disclosure, the spectrometer arrangement comprises a first optical element, which is arranged or configured in such a way that a second spectrum of a second part of the radiation comprising a second predeterminable wavelength range differing from the first can be acquired by means of the detector unit.

Embodiments disclosed herein include an optical sensor system. In an embodiment, the optical sensor system comprises a processing chamber and a sensor. In an embodiment, the sensor comprises a first diffraction grating oriented in a first direction, a second diffraction grating oriented in a second direction, and a detector for detecting electromagnetic radiation diffracted from the first grating and the second grating. In an embodiment, the optical sensor system further comprises an optical coupling element, where the optical coupling element optically couples an interior of the processing chamber to the sensor.