A two-dimensional terahertz radiation detector includes a spectral conversion element, an array of microlenses, and a matrix image sensor. Such a detector can be particularly compact, light, and inexpensive. For some embodiments, it can be used to produce multispectral images of an external scene, from terahertz radiation that originates from the scene.

A spectral imaging device comprises: an optical modifier system (SYS1) to form axial light beams (LB2) from received light beams (LB1), the axial light beams (LB2) being parallel with an optical axis (AX1) of the imaging device (500), a Fabry-Perot interferometer (FPI) to provide filtered axial light beams (LB3) by filtering light of the axial light beams (LB2), an image sensor (SEN1), and an array (ARR1) of lenses (LNS.sub.0,0, LNS.sub.0,1) to form a plurality of sub-images (S.sub.0,0, S.sub.0,1) on the image sensor (SEN1) by focusing light of the filtered light beams (LB3).

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 Attenuated total reflection measuring apparatus capable of Raman spectral measurement has an infrared optical instrument and a Raman module. The infrared optical instrument is disposed on an ATR prism side of a sample, and is provided to irradiate the ATR prism with an infrared light, and collect the infrared light from the ATR prism. The Raman module is disposed on a side opposite to the ATR prism side relative to the sample, and has a guide tube that outputs an excitation light from an excitation light source to the sample, and a lens portion disposed inside thereof. An end of the guide tube is in a position to push the sample to the ATR prism. The Raman module has a lens position adjustment mechanism that moves the lens portion along an optical axis, and a spectroscope that detects a Raman scattering light collected by the lens portion.

The light extraction device, the detection equipment and the operation method thereof are provided. The light extraction device includes at least one light splitting unit, each of the at least one light splitting unit includes a color separation grating, configured to separate light incident on the color separation grating into a plurality of light beams that are collimated and propagated in different directions and have different colors; a first lens, disposed corresponding to the color separation grating and configured to converge the plurality of light beams; and a first pinhole, located on a side of the first lens away from the color separation grating and correspondingly arranged with the first lens. The first lens is configured to converge a light beam having a preset color in the plurality of light beams to the first pinhole and allow the light beam having the preset color to exit.

The present disclosure provides a radio frequency tagging optical spectrometer, comprising: a dynamic dispersion device, the dynamic dispersion device receiving a beam comprising more than two wavelength components and being driven by driving radio frequency signals, and the dynamic dispersion device encoding the intensity of each wavelength component into the amplitude of a different beat radio frequency signal based on different driving radio frequency signals, wherein the beat frequency of the different beat radio frequency signal is equal to the frequency of the corresponding driving radio frequency signal; a single-channel photodetector for detecting the sum of beat radio frequency signals formed by adding all the beat radio frequency signals; and a processing unit for performing Fourier transform on the sum of the beat radio frequency signals to obtain a spectrum or an associated radio frequency spectrum by which the optical spectrum is obtained.

A system for testing a spectral response speed of a tunable filter is disclosed, which includes a collimating light source, a beam splitting element, a focusing lens, and an image recording device of light spot position arranged successively. The tunable filter is disposed between the collimating light source and the beam splitting element and configured to be continuously tuned within a certain wavelength range during testing. The beam splitting element is used to form light beams of different wavelength bands passing through the tunable filter into diffracted beams or refracted beams corresponding to different wavelength bands. The focusing lens is used to perform focusing. The image recording device of light spot position is used to record change information about positions where the diffracted beams or refracted beams corresponding to different wavelength bands are imaged.

Embodiments of the systems can be configured to receive electromagnetic emissions of a substrate (e.g., a build material of a part being made via additive manufacturing) by a detector (e.g., a multi-spectral sensor) and generate a ratio of the electromagnetic emissions to perform spectral analysis with a reduced dependence on location and orientation of a surface of the substrate relative to the multi-spectral sensor. The additive manufacturing process can involve use of a laser to generate a laser beam for fusion of the build material into the part. The system can be configured to set the multi-spectral sensor off-axis with respect to the laser (e.g., an optical path of the multi-spectral sensor is at an angle that is different than the angle of incidence of the laser beam). This can allow the multi-spectral sensor to collect spectral data simultaneously as the laser is used to build the part.

In a direct stimulus value reading type colorimetric photometer, first, second, and third colorimetric optical systems have spectral responsivities approximate to first, second, and third parts of the color matching function, respectively. A deriving unit derives a colorimetric value corresponding to a case in which the color matching function is selected as an evaluation function for colorimetry and a photometric value corresponding to a case in which the spectral luminous efficiency is selected as an evaluation function for photometry (i.e. “CASE”) from three signals. The spectral luminous efficiency is not consistent with any one of the first, second, and third parts. A fourth colorimetric optical system may have spectral responsivity approximate to the spectral luminous efficiency, and the deriving unit may derive the colorimetric value corresponding to the CASE from a fourth signal.

Systems, apparatuses, and methods for multi-application optical sensing are provided. For example, an optical sensing apparatus can include a photodetector array, a first circuitry, and a second circuitry. The photodetector array includes a plurality of photodetectors, wherein a first subset of the plurality of photodetectors are configured as a first region for detecting a first optical signal, and a second subset of the plurality of photodetectors are configured as a second region for detecting a second optical signal. The first circuitry, coupled to the first region, is configured to perform a first function based on the first optical signal to output a first output result. The second circuitry, coupled to the second region, is configured to perform a second function based on the second optical signal to output a second output result.