A hyperspectral imaging apparatus based on a monolithic or free space optical spatial heterodyne spectrometer (SHS) design, array detector, electromagnetic radiation source, and optical collection element is described. The apparatus enables the simultaneous acquisition of spatially isolated Fizeau fringe patterns, each having an encoded light product that is decoded to produce a spectral fingerprint of the interrogated object. Features specific to the SHS, such as a large entrance aperture, large acceptance angle, and no moving parts, enable a variety of optical collection schemes including lens arrays, solid-core and hollow core waveguides, and others. In one example, a microlens array (MLA) is configured with the hyperspectral imaging apparatus to simultaneously image many hundred spatially isolated Fizeau fringe patterns while interrogating an object using an electromagnetic radiation source. Each Fizeau fringe pattern recorded by the array detector is decoded to produce a full Raman or laser-induced breakdown spectroscopy (LIBS) spectrum. Compared to prior art, the hyperspectral imaging apparatus overcomes the primary limitations of needing to trade time resolution for both spectral and spatial data density because the imaging apparatus simultaneously acquires both spectral and special information. Based on the selection and configuration of diffraction gratings, the grating aperture size, Littrow wavelength (i.e., heterodyne wavelength), and optical collection configuration, the apparatus can be tailored to produced low or high spectral resolution with a spectral bandpass that covers a portion or the entire Raman spectral range (up to 4200 cm.sup.−1) and for LIBS as well.

A temperature compensation method for wavelength monitoring using spectrometers on photonic integrated chips and a related temperature-compensated wavelength monitoring device include an optical filter of the chip filters a source signal to provide at least one spectral reference line to a first spectrometer to detect thermal wavelength drifts thereof. At least one spectral line to be monitored is received by the same or another spectrometer of the chip to detect wavelength shifts thereof. The detected thermal drift of the reference line is compared to calibrated thermal drifts for the reference line which is associated with a calibrated thermal drift for the spectral response curve of the spectrometer receiving the spectral line to be monitored. A thermal drift rate for the response curve of the optical filter differs from a thermal drift rate for the response curve of the first spectrometer at least by an amount.

A device for measuring optical spectra at high speed and with high resolution using tunable optical laser comb sources. In one embodiment there is provided a first tunable comb laser source and a second tunable comb laser source whereby the wavelength of each comb laser source is chosen such that the combination of the two sources provides a continuous spectral coverage over a band in an optical spectrum under a selected wavelength tuning condition. By overlapping the two comb sources in the manner described the deadzone issue is overcome in the most spectrally efficient way possible.

Systems, devices, and methods for detecting agrochemicals in environments associated with agricultural equipment are described. Certain agrochemicals that are formulated for being detected using the systems, devices, and methods disclosed herein are also described. The devices, systems, and methods disclosed herein are generally configured to use spectral characteristics to detect agrochemicals in an environment associated with agricultural equipment. The spectral characteristics can be analyzed in various ways to provide different types of information about the agrochemicals and/or the environment.

An optical module includes a support layer, a device layer which is provided on the support layer, and a movable mirror which is mounted in the device layer. The device layer has a mounting region which is penetrated by the movable mirror, and a driving region which is connected to the mounting region. A space corresponding to at least the mounting region and the driving region is formed between the support layer and the device layer. A portion of the movable mirror is positioned in the space.

An apparatus for measuring time-resolved optical spectrum includes a light source, a sensor for collecting, forming, manipulating and measuring the intensity of the optical radiation, and a controller coupled to the light source and sensor. The sensor includes at least one optical delay element to provide a time delay to a first portion of the optical radiation. The sensor arrangement further includes an optical spectral disperser to split the delayed first portion and the second portion of the optical radiation into dispersed radiation having a plurality of wavelengths, and a sensor element configured to receive each wavelength of the dispersed radiation on a different spatial region, and measure the light intensity associated with each wavelength of the dispersed radiation. The controller collects the light intensity associated with each wavelength of the dispersed radiation measured by the sensor element to form a time-resolved optical spectrum.

Configurations for a diffraction grating design and methods thereof are disclosed. The diffraction grating system can include an input waveguide located at a first location on or near a Rowland circle and multiple output waveguides located at a second and third location on or near the Rowland circle. The input waveguide may be located between the output waveguides and this configuration of input and output waveguides can reduce the footprint size of the device. In some examples, the optical component can function as a de-multiplexer. Additionally, the optical component may separate the input wavelength band into two output wavelength bands which are separated from one another by approximately 0.1 μm.

The disclosure relates to an optical spectrometer (1) for spectrally resolved two-dimensional imaging of an object (0), comprising a dispersing device (2) arranged to disperse radiation from object (0), a multi-lens array arrangement (3) arranged to receive the dispersed radiation from the dispersing device (2), a two-dimensional detector (4) arranged to receive the dispersed radiation as directed by the multi-lens array arrangement (3), wherein the optical spectrometer (1) further comprises a collimating arrangement (5) for collimating the radiation from object (0) before the radiation reaches the dispersing device (2), the collimating arrangement (5) comprising a diffusing plate (6) for diffusing the radiation and an optical micro-channel component (7) arranged to receive the diffused radiation comprising a plurality of parallel and linear optical micro-channels directed towards the dispersing device (2). The disclosure further relates to a method for spectrally resolved two-dimensional imaging of an object (0).

A method for generating a illumination dual-comb signal that provides a low frequency train of interferograms (180) readable by a regular video-rate camera (160) comprising N pixels and a sampling frequency of V Hz to extract hyperspectral information (170), the method comprising providing a monochromatic signal, splitting the monochromatic signal in two split monochromatic signals, frequency shifting each monochromatic signal with an offset frequency below

[00001]$\frac{V}{2}\mathrm{Hz},$

generating two frequency combs having a difference in repetition below

[00002]$\frac{V}{2}\mathrm{Hz}$

by a nonlinear modulation of the two split monochromatic signals, generate the illumination dual-comb signal, Illuminating a target and employing a video-rate camera (160) to read a low frequency train of interferograms (180) based on a reflected and/or transmitted signal of the illumination dual-comb signal and performing Fourier transformation of the low frequency train of interferograms (180) detected by each pixel from the N pixels to extract the hyperspectral information (170).

An optical property evaluation apparatus evaluates an optical property of an evaluation object, and includes a light source, a polarization beam splitter, a polarization adjuster, a first detector, a second detector, and an analyzer. The analyzer obtains a reflectance when linearly polarized light in a specific direction is incident on the evaluation object based on the detection result by the first detector when the light with which the evaluation object is irradiated is set to be the linearly polarized light in the specific direction. The analyzer obtains a phase property at the reflection of the evaluation object based on the detection result by the first detector or the second detector when the light with which the evaluation object is irradiated is set to have a polarization state different from the linearly polarized light in the specific direction, and a Jones matrix.