A compact, catadioptric and athermal imaging spectrometer is disclosed. A telecentric light (1) incident from a slit (2) is folded or refracted by an object-side prism (3) to enter a plano-convex lens (4); after being refracted by the plano-convex lens (4) and a meniscus lens (5), and refracted and reflected by a thick catadioptric lens (6), said telecentric light is incident onto a convex grating (7) in the form of a convergent beam; and after said beam is diffracted, spectral division is implemented. The divergent beam is sequentially refracted and reflected by the thick catadioptric lens (6), and refracted by the meniscus lens (5) and the plano-convex lens (4) to enter an image-side prism (8). Said beam is folded or refracted and filtered, and imaged on a focal plane (10) to realize spectral imaging.

A compact, catadioptric and athermal imaging spectrometer is disclosed. A telecentric light (1) incident from a slit (2) is folded or refracted by an object-side prism (3) to enter a plano-convex lens (4); after being refracted by the plano-convex lens (4) and a meniscus lens (5), and refracted and reflected by a thick catadioptric lens (6), said telecentric light is incident onto a convex grating (7) in the form of a convergent beam; and after said beam is diffracted, spectral division is implemented. The divergent beam is sequentially refracted and reflected by the thick catadioptric lens (6), and refracted by the meniscus lens (5) and the plano-convex lens (4) to enter an image-side prism (8). Said beam is folded or refracted and filtered, and imaged on a focal plane (10) to realize spectral imaging.

A protective sheath having a closed end and an open end is sized to receive a hand held spectrometer. The spectrometer can be placed in the sheath to calibrate the spectrometer and to measure samples. In a calibration orientation, an optical head of the spectrometer can be oriented toward the closed end of the sheath where a calibration material is located. In a measurement orientation, the optical head of the spectrometer can be oriented toward the open end of the sheath in order to measure a sample. To change the orientation, the spectrometer can be removed from the sheath container and placed in the sheath container with the calibration orientation or the measurement orientation. Accessory container covers can be provided and placed on the open end of the sheath with samples placed therein in order to provide improved measurements.

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 device for determining the surface topology and associated color of a structure, such as a teeth segment, includes a scanner for providing depth data for points along a two-dimensional array substantially orthogonal to the depth direction, and an image acquisition means for providing color data for each of the points of the array, while the spatial disposition of the device with respect to the structure is maintained substantially unchanged. A processor combines the color data and depth data for each point in the array, thereby providing a three-dimensional color virtual model of the surface of the structure. A corresponding method for determining the surface topology and associate color of a structure is also provided.

Apparatus and methods for spectral analysis of a sample are described, for example for carrying out Raman or other optical or spectroscopic analysis of samples such as pharmaceutical dosage forms, including oral solid dosage forms such as tablets or capsules. Such apparatus may comprise delivery optics arranged to direct probe light to a delivery region of the sample, collection optics arranged to collect probe light scattered from a collection region of the sample, and a spectrometer having an entrance port, the spectrometer being arranged to receive the collected probe light from the collection optics at the entrance port of the spectrometer, and to detect spectral features in the received probe light. In particular, the collection optics may comprise Koehler integration optics arranged to process the collected probe light such that the collected light from each point of the collection region is distributed across the entrance port of the spectrometer.

Apparatuses, systems, and methods for Raman spectroscopy are described. In certain implementations, a spectrometer is provided. The spectrometer may include a plurality of optical elements, comprising an entrance aperture, a collimating element, a volume phase holographic grating, a focusing element, and a detector array. The plurality of optical elements are configured to transfer the light beam from the entrance aperture to the detector array with a high transfer efficiency over a preselected spectral band.

An optical sensor system may include a light source. The optical sensor system may include a concentrator component proximate to the light source and configured to concentrate light from the light source with respect to a measurement target. The optical sensor system may include a collection component that includes an array of at least two components configured to receive light reflected or transmitted from the measurement target. The optical sensor system may include may a sensor. The optical sensor system may include a filter provided between the collection component and the sensor.

A Raman sensor includes a light source assembly having a plurality of light sources configured to emit light to a plurality of skin points of skin, each of the plurality of skin points having a predetermined separation distance from a light collection region of the skin from which Raman scattered light is collected; a light collector configured to collect the Raman scattered light from the light collection region of the skin; and a detector configured to detect the collected Raman scattered light.

A spectrometer for detecting an electromagnetic (EM) wave spectrum having one or more wavelength components within a spectral band of interest, and a method of detecting an electromagnetic (EM) wave spectrum having one or more wavelength components within a spectral band of interest. The method uses an entrance aperture; a dispersion and imaging optics containing at least one dispersion element; an exit aperture; a collection optics; and at least one single-pixel detector, each single-pixel detector sensitive to one or more of the wavelength components; and the method comprises the steps of spatially encoding at least one entrance slit of the entrance aperture along a direction substantially transverse to a direction of dispersion of the dispersion and imaging optics; creating, using the dispersion and imaging optics, dispersed images of the entrance aperture on a plane of the exit aperture, such that respective images at the different wavelength components are offset by different amounts of displacements along the direction of dispersion; spatially encoding a plurality of exit slits of the exit aperture along the direction substantially transverse to the direction of dispersion, wherein the exit aperture comprises a plurality of exit slits arranged in the direction of dispersion; gathering, using the collection optics, a total EM wave energy that enters the entrance aperture and exits the exit aperture to one of the at least one single-pixel detectors; changing at least one of an encoding pattern of the at least one entrance slits and an encoding pattern of the plurality of exit slits for a number of times; and measuring the output of the at least one detector for respective ones of the number of times for reconstructing the EM wave spectrum.