Abstract:
A fiber optic probe assembly is provided. The probe comprises a first optical system and a second optical system, a delivery light guide comprising one or more than one delivery optical fiber for transmitting excitation radiation from a radiation source disposed at a proximal end of the light guide to the first optical system. The first optical system comprising one or more than one first optical element for forming a substantially collimated illumination beam from the excitation radiation. An optically opaque tubular sleeve is fitted over the first optical system to optically isolate the first optical system and the delivery light guide from the second optical system. The second optical system comprising one or more than one second optical element for gathering optical radiation scattered from a sample and forming the optical radiation into a collection beam. A collection light guide comprising one or more than one collection optical fiber receives the collection beam and transmits the collection beam to an analyzer. The first and second optical systems are disposed within a housing so that an emission cone of the first optical system and an acceptance cone of the second optical system substantially overlap. A spectroscopic measurement system comprising the optic fiber probe is also provided.
Abstract:
A spectroscopic unit and spectroscopic device according to the present invention are provided with a filter that is provided with a plurality of optical filter elements disposed in order from the entrance side to the exit side of light under measurement and has different transmission wavelengths corresponding to entrance positions along a first direction. A first optical filter element from among the plurality of optical filter elements is tilted with respect to a second optical filter element disposed adjacently to the first optical filter element as a result of the first optical filter element being rotated by a prescribed angle with a third direction that is perpendicular to both the first direction and s second direction from the entrance side to the exit side as the axis of rotation thereof or being rotated by a prescribed angle with the first direction as the axis of rotation thereof.
Abstract:
The present disclosure provides for a system and method for detecting unknown materials. A test data set, which may comprise a hyperspectral data set, is generated representative of a first location. The test data set may be analyzed to determine a second location which may be interrogated using a Raman spectroscopic device to generate a Raman data set. The Raman data set may be analyzed to associated an unknown material with a known material such as: a chemical material, a biological material, an explosive material, a hazardous material, a drug material, and combinations thereof.
Abstract:
A system and method for the detection and identification of explosives and explosive residues using a combination of SWIR, Raman, and LIBS spectroscopy techniques, including imaging. A region of interest may be surveyed to identify a target area, wherein the target area comprises at least one unknown material. This surveying may be accomplished using visible imagery or SWIR imagery. The target area may be interrogated using Raman spectroscopy and LIBS spectroscopy to identify the unknown material. SWIR techniques may also be used to interrogate the target area. Fusion algorithms may also be applied to visible images, SWIR data sets, Raman data sets, and/or LIBS data sets.
Abstract:
The disclosure relates generally to methods and apparatus for using a fiber array spectral translator-based (“FAST”) spectroscopic system for improved imaging, spectral analysis, and interactive probing of a sample. In an embodiment, the confocality of a fiber array spectral translator-based spectroscopic system is improved through the use of structured illumination and/or structured collection of photons. User input may be received and acted upon to allow a user to interactively in real time and/or near real time view and analyze specific regions of the sample.
Abstract:
A system for determining gas compositions includes a probe, inserted into a source of gaseous material, the probe having a gas permeable sensor tip and being capable of sending and receiving light to and from the gaseous material, a sensor body, connected to the probe, situated outside of the source and a fiber bundle, connected to the sensor body and communicating light to and from the probe. The system also includes a laser source, connected to one portion of the fiber bundle and providing laser light to the fiber bundle and the probe a Raman spectrograph, connected to another portion of the fiber bundle, receiving light from the probe and filtering the received light into specific channels and a data processing unit, receiving and analyzing the received light in the specific channels and outputting concentration of specific gas species in the gaseous material based on the analyzed received light.
Abstract:
A spectroscopic system according to the present invention 10 comprises: an optical fiber bundle 12 whose emitting end 12a is arranged in a vertical direction; a slit 16 which is arranged so as to oppose the emitting end 12a of the optical fiber bundle 12; spectroscopic element arrangement means 20 which can switchably arrange either a first diffraction grating 23 in which grooves extending along the vertical direction are arranged in a horizontal direction at a predetermined groove density, or a second diffraction grating 24 in which grooves extending along the vertical direction are arranged in the horizontal direction at a groove density larger than that of the first diffraction grating 23, on an optical path of light which is emitted from the emitting end 12a of the optical fiber bundle 12 and passes through the slit 16; and a photomultiplier tube 30 in which a plurality of anodes 53 extending along the vertical direction are arranged in the horizontal direction.
Abstract:
A spectroscopic system according to the present invention 10 comprises: an optical fiber bundle 12 whose emitting end 12a is arranged in a vertical direction; a slit 16 which is arranged so as to oppose the emitting end 12a of the optical fiber bundle 12; spectroscopic element arrangement means 20 which can switchably arrange either a first diffraction grating 23 in which grooves extending along the vertical direction are arranged in a horizontal direction at a predetermined groove density, or a second diffraction grating 24 in which grooves extending along the vertical direction are arranged in the horizontal direction at a groove density larger than that of the first diffraction grating 23, on an optical path of light which is emitted from the emitting end 12a of the optical fiber bundle 12 and passes through the slit 16; and a photomultiplier tube 30 in which a plurality of anodes 53 extending along the vertical direction are arranged in the horizontal direction.
Abstract:
The invention provides an imaging spectrometer that provides a wide field-of-view camera and spectrometer for spectral imaging of a large two-dimensional area of the Earth's surface from an orbiting satellite or airplane. The wide field-of-view camera fore-optics includes spherical optical elements arranged monocentrically. The spectrometer includes an all-reflective coupling design that transfers the curved optical image to one or more compact imaging spectrometers. The spectrometers preferably comprise a spherical convex holographic grating and associated reflective optics for dispersing a collimated optical beam into its spectral components and focusing the spectral image onto a planar detector array. The instrument described herein is designed to operate in a "pushbroom" fashion, that is, the forward motion of the satellite or airplane generates the spatial dimension of the resulting image. Because of its compact optical design and because no additional scanning equipment is required to scan the Earth's surface, the instrument is very compact and light-weight.
Abstract:
A method and system for calibrating color filters employed in polychromatic imaging of a subject includes a scanning mirror (28), telescope (30), filters (104), and a detector array (60) employed for both imaging and calibration processes. A bundle (44) of optical fibers is employed for producing a slit-shaped beam of solar rays which are collimated and applied to a diffraction grating plate (54) or prism (72) to produce a set of dispersed solar rays. The dispersion is based on color. In one position of the scanning mirror, rays from a subject (12) to provide an image are directed through the telescope and scanned across the filters (104) and detectors (102). In another position of the scanning mirror, the set of dispersed solar rays is scanned past the filters and the detectors. Imaging data outputted by the detectors is collected for producing an image (112) of the subject. Data of the dispersed rays is collected for calibrating the color filters. A stored reference color profile (92) of each filter is correlated with the calibration data ( 90) to obtain a set of correction terms which are employed for altering the image data to compensate for any drift in the color characteristics of the filters. A broad band detector detects Fraunhofer spectral lines to serve as a reference standard wavelength for alignment of the system.