A first wavelength-shifted exit signal is interfered with a first reference beam and a second wavelength-shifted exit signal is interfered with a second reference beam. The first wavelength-shifted exit signal and the second wavelength-shifted exit signal have different wavelengths. A first and second interference pattern are captured by an image sensor in a single image capture. The first reference beam is incident on the image sensor at a first reference angle and the second reference beam is incident on the image sensor at a second reference angle different from the first reference angle.

A gain switched dual comb spectroscopy device for spectroscopically detecting a sample substance, comprising a first slave laser light source configured to generate a first frequency comb having a first comb free spectral range, and a second slave laser light source configured to generate a second frequency comb having a second comb free spectral range which is different from the first comb free spectral range. A master laser light source is configured to inject seed light in to both slave laser light sources therewith to injection lock the generation of both the first and the second frequency combs. A photodetector part is arranged to combine the first and the second frequency combs and to detect a beat signal the spectrum of which comprises a third frequency comb including beat tones produced by interference between the combined first and second frequency combs. The device comprises a sample detection area configured for receiving the sample for detection and for directing at least one of the first and the second frequency comb to the photodetector part via the sample detection area.

The present disclosure concerns a sensor for the acquisition of an optical signal modulated at an acoustic frequency, including a plurality of pixels, each including: a photodiode; an integration circuit configured to, at each period of the modulated optical signal, integrate a photocurrent delivered by the photodiode successively into K capacitors, K being an integer greater than or equal to 2; and a phase detection circuit configured to detect an order in the crossing of a predetermined voltage threshold by the K capacitors and to generate, according to the detected order, a signal representative of the phase of the modulated optical signal.

A photo-thermal interferometer for measuring the light absorption of an aerosol or gas comprises a first laser source emitting a laser beam and a beam splitter adapted to divide the laser beam into a probe beam and a reference beam. The interferometer further comprises first optical elements which are adapted to direct the probe beam such that it passes through the aerosol and interferes with the reference beam thereafter thereby causing interference patterns. A detector detects the interference patterns. The interferometer further comprises a second laser source configured to emit a pump beam for transferring energy to the aerosol. Second optical elements are adapted to direct the pump beam such that it overlaps with the probe beam at least partially in the aerosol or gas. At least one of the second optical elements modifying the pump beam is an axicon.

A first wavelength-shifted exit signal is interfered with a first reference beam and a second wavelength-shifted exit signal is interfered with a second reference beam. The first wavelength-shifted exit signal and the second wavelength-shifted exit signal have different wavelengths. A first and second interference pattern are captured by an image sensor in a single image capture. The first reference beam is incident on the image sensor at a first reference angle and the second reference beam is incident on the image sensor at a second reference angle different from the first reference angle.

A process for detecting the sensitivity of one or more polymers and/or of one or more mixtures of polymers to a compound, including the steps of exposing a plurality of individualized micro-deposits including the polymer(s) and/or the mixture(s) of polymers to the compound, and detecting, by interferometry, a variation in appearance of an assembly of micro-deposits exposed to the compound and or a variation in the dimensions and/or refractive index of at least one of the micro-deposits exposed to the compound, linked to an interaction between the polymer(s) and or the mixture(s) of polymers and the compound.

A method and an interferometric device for spectroscopically or spectrometrically examining a sample, comprising: a) generating a laser beam having a wavelength, b) splitting the laser beam into a measurement beam and a reference beam, c) interacting the sample with the measurement beam, d) interacting a reference with the reference beam, e) overlaying the measurement beam and the reference beam, f) detecting a first output beam, g) detecting a second output beam, h) forming a differential signal between the first output signal and the second output signal, i) controlling the differential signal to a predefined target value, j) determining a refractive index of the sample from the adjustment of the phase difference between the measurement beam and the reference beam, k) repeating steps a) to j) for additional wavelengths of the laser beam.

A sensitivity boosted laser dispersion spectroscopy system for sensing a sample in a sample cell or in an open path crossing the sample. The system includes a local oscillator arm and a sample arm containing the sample cell or the open path crossing the sample. A laser source is configured to generate a first light beam directed along the sample arm and a second light beam, the second light beam being frequency shifted and directed along the local oscillator arm. An intensity modulator/phase modulator/frequency shifter is disposed in the sample arm configured to generate a multi-frequency beam having known frequency spacing which is then passed through the sample cell to generate a sample arm output. A beam combiner is configured to combine the sample arm output and the second light beam from the local oscillator arm and generate a combined beam. A photodetector is configured to detect the combined beam for sensing the sample in the sample cell.

An arrangement for measuring gas concentrations in a gas absorption method, wherein the arrangement includes a plurality of light sources, a measuring cell, at least one measuring receiver and an evaluation apparatus. The measuring cell has a narrow, longitudinally-extended beam path with an entrance-side opening diameter B and an absorption length L with L>B, wherein the measuring cell has a gas inlet and a gas outlet wherein a plurality of light sources of different wavelength spectra is grouped into a first light source group wherein an optical homogeniser is interposed between the first light source group and the measuring cell, wherein, in particular, the homogeniser is coupled to the light source group directly or via a common optical assembly.

A fluid analyzer includes a substrate, a quantum cascade laser formed on a surface of the substrate and including a first light-emitting surface and a second light-emitting surface facing each other in a predetermined direction parallel to the surface, a quantum cascade detector formed on the surface and including the same layer structure as the quantum cascade laser and a light incident surface facing the second light-emitting surface in the predetermined direction, and an optical element disposed on an optical path of light emitted from the first light-emitting surface across an inspection region in which a fluid to be analyzed is to be disposed and reflecting the light to feed the light back to the first light-emitting surface.