A spectrometer arrangement with two-dimensional spectrum, comprising a first dispersing element for spectral separation of radiation in a main dispersion direction, an imaging optics for imaging the radiation entering into the spectrometer arrangement through an entrance slit in an image plane for producing a two-dimensional spectrum, and a detector array with a two-dimensional arrangement of a plurality of detector elements in the image plane, wherein a reflector, a refractor, and/or a lens array are arranged in the beam path at a location where the dispersed, monochromatic beams are separated from one another, and the reflector, the refractor, and/or the lens array have a surface in the form of a freeform surface, such that area occupied by selected images of the entrance slit in the case of different wavelengths in the image plane is optimized over a selected spectral region of the two-dimensional spectrum.

A tunable spectral filter includes a first tunable dispersive element, a first optical element, a spatial filtering element located at the focal plane, a second optical element, and a second dispersive element. The first tunable dispersive element introduces spectral dispersion to an illumination beam with an adjustable dispersion. The first optical element focuses the illumination beam at a focal plane in which a distribution of a spectrum of the spectrally-dispersed illumination beam at the focal plane is controllable by adjusting the dispersion of the first tunable dispersive element. The spatial filtering element filters the spectrum of the illumination beam based on the distribution of the spectrum of the illumination beam at the focal plane. The second optical element collects the spectrally-dispersed illumination beam transmitted from the spatial filtering element. The second tunable dispersive element removes the dispersion introduced by the first tunable dispersive element from the illumination beam.

A spectral radiation gas detector has at least one lenslet with a circular blazed grating for diffraction of radiation to a focal plane. A detector is located at the focal plane receiving radiation passing through the at least one lenslet for detection at a predetermined diffraction order. A plurality of order filters are associated with the at least one lenslet to pass radiation at wavelengths corresponding to the predetermined diffraction order, each filter blocking a selected set of higher orders. A controller is adapted to compare intensity at pixels in the detector associated with each of the plurality of order filters and further adapted to determine a change in intensity exceeding a threshold.

Aspects of blending data detected by a monochromator over multiple wavelength ranges is described herein. In one embodiment, the monochromator includes a diffraction grating, a grating drive motor that rotates the diffraction grating to provide, by diffraction of broadband light, first dispersed wavelengths of light and second dispersed wavelengths of light, a detector that detects a first reflection from the first dispersed wavelengths of light and a second reflection from the second dispersed wavelengths of light, and processing circuitry that blends data values from the first reflection and data values from the second reflection together to provide a spectrum of combined data values. By blending data detected over multiple ranges, measurements of relatively high precision and quality can be provided over a wider spectral range.

A spectrometer arrangement with two-dimensional spectrum, comprising a first dispersing element for spectral separation of radiation in a main dispersion direction, an imaging optics for imaging the radiation entering into the spectrometer arrangement through an entrance slit in an image plane for producing a two-dimensional spectrum, and a detector array with a two-dimensional arrangement of a plurality of detector elements in the image plane, wherein a reflector, a refractor, and/or a lens array are arranged in the beam path at a location where the dispersed, monochromatic beams are separated from one another, and the reflector, the refractor, and/or the lens array have a surface in the form of a freeform surface, such that area occupied by selected images of the entrance slit in the case of different wavelengths in the image plane is optimized over a selected spectral region of the two-dimensional spectrum.

Aspects of blending data detected by a monochromator over multiple wavelength ranges is described herein. In one embodiment, the monochromator includes a diffraction grating, a grating drive motor that rotates the diffraction grating to provide, by diffraction of broadband light, first dispersed wavelengths of light and second dispersed wavelengths of light, a detector that detects a first reflection from the first dispersed wavelengths of light and a second reflection from the second dispersed wavelengths of light, and processing circuitry that blends data values from the first reflection and data values from the second reflection together to provide a spectrum of combined data values. By blending data detected over multiple ranges, measurements of relatively high precision and quality can be provided over a wider spectral range.

A spectral instrument including a light source configured to produce a light beam, the light beam comprising a plurality of wavelengths, and the light beam being about collimated or pseudo-collimated. The spectral instrument also includes a spectral dispersion device in optical communication with the light source. The spectral instrument also includes a screen disposed in the optical path after the spectral dispersion device. The screen comprises a material configured to be substantially opaque to at least some of the plurality of wavelengths. The screen is sized and dimensioned to at least partially block selected ones of the plurality of wavelengths. The screen is movable with respect to an axis of the screen. The spectral instrument also includes an imaging lens disposed in the optical path and disposed either after the screen or before the screen.

A system and method for spectroscopic mapping, with configurable spatial resolution, of an object include a fiber optic bundle having a plurality of optical fibers arranged in a first array at an input end with each of the plurality of optical fibers spaced one from another and arranged in at least one linear array at an output end. A first mask defining a plurality of apertures equal to or greater in number than the plurality of optical fibers is positioned between an object to be imaged and the input end of the fiber optic bundle. An imaging spectrometer is positioned to receive light from the output end of the fiber optic bundle and to generate spectra of the object. A sensor associated with the imaging spectrometer converts the spectra to electrical output signals for processing by an associated computer.