Abstract:
A system and method for detection and identification of unknown samples using a combination of Raman and LIBS detection techniques. A first region of a sample and a second region of a sample are illuminated using structured illumination to thereby generate a first plurality of interacted photons and a second plurality of interacted photons. This first plurality and second plurality of interacted photons may be passed through a fiber array spectral translator device. Said first plurality of interacted photons are assessed using Raman spectroscopy to thereby generate a Raman data set. Said second plurality of interacted photons are assessed using LIBS spectroscopy to thereby generate LIBS data set. These data sets may be analyzed to identify the sample. These data sets may also be fused for further analysis.
Abstract:
A method and apparatus for automated spectral calibration of a spectroscopy device. A method for simultaneous calibration and spectral imaging of a sample by: simultaneously illuminating the sample and a calibrant with a plurality of illuminating photons; receiving, at the spectrometer, a first plurality of photons collected from the sample and a second plurality of photons collected from the calibrant; forming a calibrant spectrum from the first plurality of collected photons and a sample spectrum from the second plurality of collected photons; comparing the calibrant spectrum with a reference spectrum of the calibrant to determine a wavelength-shift in the calibrant spectrum; applying the wavelength-shift to the sample spectrum to obtain a calibrated sample spectrum.
Abstract:
A system and method for performing multispectral color addition imaging. An optical image is obtained for a sample scene comprising one or more target materials. Spectroscopic data is obtained for one or more target materials. A first and second waveband of interest are obtained for one or more target materials. A ratio of the first and second wavebands of interest is obtained and compared to one or more ranges of threshold values. Based on this comparison, a result is displayed wherein this result comprises a pseudo color overlay on said optical image. The pseudo color image may comprise one or more pseudo colors assigned to one or more target materials so as to differentiate and identify the target materials present in the sample scene.
Abstract:
A sample is illuminated to thereby generate a plurality of first interacted photons selected. The first interacted photons are assessed using a visible imaging device to thereby determine an area of interest in the sample. The area of interest is illuminated to thereby generate a plurality of second interacted photons. The second interacted photons are assessed using a spectroscopic device to thereby generate a SWIR data set representative of said area of interest. A database is searched wherein said database comprises a plurality of known SWIR data sets associated with an explosive material. The data sets comprise at least one of: a plurality of SWIR spectra and a plurality of spatially accurate wavelength resolved SWIR images. An explosive material in the area of interest is thereby identified as a result of the search.
Abstract:
A method and a portable device for assessing the occurrence of an agent in a sample. A sample is illuminated with photons emanating from a portable device to produce photons reflected, emitted, or absorbed from a set of multiple points in the sample having a defined geometric relationship. The portable device is used to simultaneously illuminate the sample and analyze the photons reflected, emitted, or absorbed from the set of multiple points using spectroscopic methods, including infrared, fluorescence, and UV/visible. The agent assessed may include a hazardous agent, a chemical agent, a biological agent, a microorganism, a bacterium, a protozoan, a virus, and combinations thereof.
Abstract:
A system and method to automatically obtain spectra for samples. The method involves a two phase process including a photobleaching phase and a spectral acquisition phase. In the photobleaching phase, a series of spectral data sets of a sample are collected. A relative difference is determined between the background of subsequent spectral data sets is determined and compared to a predetermined threshold value. If threshold difference is less than the relative difference between the background of subsequent spectral data sets, the steps of collecting a series of spectra data sets is automatically repeated. In the spectrum acquisition phase, a series of Raman data sets of the sample are collected until a target SNR is obtained.
Abstract:
The disclosure generally relates to a method and apparatus for a fiberscope. In one embodiment, the disclosure relates to a chemical imaging fiberscope for imaging and collecting optical spectra from a sample having at least one illumination fiber for transmitting light from a first an a second light source to a distal end of a fiberscope; a dichroic mirror disposed at said distal end of the fiberscope such that light from said first light source passes substantially straight through said mirror and light of a predetermined wavelength from said second light source is substantially reflected by said mirror toward said sample to thereby illuminate said sample; and at least one collection fiber for receiving light from said illuminated sample and transmitting the received light to an optical device.
Abstract:
A system and method for depositing a sample of a threat agent onto a substrate. A single illumination source illuminates the threat agent deposited on the substrate with a plurality of photons to thereby produce elastic scattered photons and Raman scattered photons. The threat agent on the substrate is identified. The system and method operate in a trigger mode that detects the presence or absence of the threat agent, and an identification mode that identifies the threat agent.
Abstract:
A system and method to search spectra databases and to identify unknown materials. A library having a plurality of sublibraries is provided wherein each sublibrary contains a plurality of reference data sets generated by a corresponding one of a plurality of spectroscopic data generating instruments associated with the sublibrary. Each reference data set characterizes a corresponding known material. A plurality of test data sets is provided that is characteristic of an unknown material, wherein each test data set is generated by one or more of the plurality of spectroscopic data generating instruments. For each test data set, each sublibrary is searched where the sublibrary is associated with the spectroscopic data generating instrument used to generate the test data set. A corresponding set of scores for each searched sublibrary is produced, wherein each score in the set of scores indicates a likelihood of a match between one of the plurality of reference data sets in the searched sublibrary and the test data set. A set of relative probability values is calculated for each searched sublibrary based on the set of scores for each searched sublibrary. All relative probability values for each searched sublibrary are fused producing a set of final probability values that are used in determining whether the unknown material is represented through a known material characterized in the library. A highest final probability value is selected from the set of final probability values and compared to a minimum confidence value. The known material represented in the libraries having the highest final probability value is reported, if the highest final probability value is greater than or equal to the minimum confidence value.
Abstract:
An ion implanted semiconductor surface is illuminated with a flood illumination of monochromatic radiation, and an image of the surface is taken using light which has been Raman scattered. The illumination and imaging system are calibrated by flood illuminating a uniformly Raman scattering surface.