A spectrally-resolved Raman water lidar, including: a transmitter unit, a receiver unit, and a data acquisition and control unit. The transmitter unit includes a seeder, a solid Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) laser, a beam expander, and a first reflecting mirror to emit a 354.8-nm laser beam. The receiver unit includes a telescope, an iris, a collimator, a second reflecting mirror, a first bandpass filter, a beam splitter, a narrow-band interference filter, a third lens, a first detector, a second bandpass filter, a coupler and a home-made dual-grating polychromator to enable simultaneous profiling of backscattered Raman spectrum signals from water vapor, water droplets and ice crystals as well as aerosol fluorescence in the atmosphere. The data acquisition and control unit includes a computer to store the acquired data and guarantee an automatic operation of the lidar system through a time-sequence circuit.

Provided is an optical system which may acquire a hyperspectral image by acquiring a spectral image of an object to be measured, which includes, to collect spectral data and train the neural network, an image forming part forming an image from an object to be measured and transmitting collimated light, a slit moving to scan the incident image and passing and outputting a part of the formed image, and a first optical part obtaining spectral data by splitting light of the image received through the slit by wavelength. Also, the system includes, to decompose overlapped spectral data and to infer hyperspectral image data through the trained neural network, an image forming part forming an image from an object to be measured and transmitting collimated light, and a first optical part obtaining spectral data by splitting light of the received image by wavelength.

An optical resonance imaging system includes a light emitting device to emit laser pulses onto a subject. The laser pulses include a first pulse and a second pulse to place the subject in an excited state. The laser pulses also include a third pulse to stimulate emission of one or more third order signals from the subject. The system also includes a spectrometer to receive the one or more third order signals and to generate spectrum signals commensurate with intensities of the one or more third order signals. The system may further include circuitry configured to analyze the spectrum signals, generate one or more images of the subject based on the analysis, and construct one or more maps of positions of the subject based on the one or more images.

A spectral imager (100) may use an entrance telescope (10) to spatially image an object (O1), at least in the across-slit direction (X), onto a physical slit (Se) of a spectrometer (20). The spectrometer (20) may include a slit homogenizer (24) such as a rod lens configured to spatially image an aperture stop (AS) in the across-slit direction (X) as a virtual slit image (Ih). Formation of a detection image (Id) which is spectrally resolved along a spectral axis (X′) may includes spatially imaging the virtual slit image (Ih), at least in the across-slit direction (X), at a detector plane (Pd). This may achieve a more homogeneous illumination of the spectrometer slit and improve measurement accuracy and reproducibility.

A polarized Raman Spectrometric system for defining parameters of a polycrystaline material, the system comprises a polarized Raman Spectrometric apparatus, a computer-controlled sample stage for positioning a sample at different locations, and a computer comprising a processor and an associated memory. The polarized Raman Spectrometric apparatus generates signal(s) from either small sized spots at multiple locations on a sample or from an elongated line-shaped points on the sample, and the processor analyzes the signal(s) to define the parameters of said polycrystalline material.

A system and method for imaging a sample using Raman spectrometry. Optical fibers having opposite first ends and second ends are arranged with the first ends and second ends in respective two-dimensional arrays. The two-dimensional arrays maintain relative positions of the optical fibers to one another from the first ends to the second ends in a way that the first end of each optical fibers of the bundle can simultaneously collect a corresponding Raman signal portion scattered from specific spatial coordinates of the area of the sample. The so-collected Raman signal portions are propagated towards the corresponding second end, from which are outputted and detected simultaneously using an array of detectors.

Correction optics (10) are disposed in an optical path directly behind an entry slit (1) of a spectrometer (100) and configured to warp a straight object line shape (A1) of the entry slit (1) into a curved object line shape (B1) from a point of view of the projection optics (2,3,4). The warping of the correction optics (10) is configured such that a curvature (R1) of the curved object line shape (B1) counteracts an otherwise distorting curvature (R5) in a projection (A5) of the straight object line shape (A1) by the projection optics (2,3,4) without the correction optics (10). As a result, the spectrally resolved image (B5) comprises a plurality of parallel straight projected line shapes formed by spectrally resolved projections of the straight object line shape (A1).

A spectrometer apparatus is disclosed. The apparatus may include light source and the light source may include a chamber for sustaining a plasma within the internal volume of the chamber. The apparatus may also include a spectrometer cavity and a windowless entrance slit. The windowless entrance slit may fluidically and optically couple the spectrometer cavity and the internal volume of the chamber of the light source. Further, the apparatus may include a diffractive element disposed within the spectrometer cavity and a window positioned at an opposite end of the spectrometer cavity from the windowless slit. The apparatus may also include a camera and a spectrometer.

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 freeform surface imaging spectrometer system including a primary mirror, a secondary mirror, a tertiary mirror, and a detector is provided. The secondary mirror is a grating having a freeform surface shape, and the grating having the freeform surface shape is obtained by intersecting a set of equally spaced parallel planes with a freeform surface. A plurality of feature rays exiting from a light source is successively reflected by the primary mirror, the secondary mirror and the tertiary mirror to form an image on an image sensor. A reflective surface of each of the primary mirror, the tertiary mirror surface and the tertiary mirror is an xy polynomial freeform surface.