Spectral Sciences Incorporated

About: Spectral Sciences Incorporated is a company organization based out in Burlington, Massachusetts, United States. It is known for research contribution in the topics: Hyperspectral imaging & Radiance. The organization has 114 authors who have published 342 publications receiving 10875 citations.

Optical Blood Coagulation Monitor and Method

Abstract: An optical blood coagulation monitor and method. The monitor has a blood sample holder, a laser with its output light directed through the blood sample, a two-dimensional detector that is able to detect light at the laser light wavelength and that has a detector output, optics for imaging onto the detector laser light that is forward scattered by the blood, and a data analysis system, responsive to the detector output, that is adapted to analyze the detected light to provide information on time-resolved coagulation and clotting properties of the blood.

A first‐principles model of spectrally resolved 5.3 μm nitric oxide emission from aurorally dosed nighttime high‐altitude terrestrial thermosphere

Abstract: [1] The spectrally resolved nighttime 5.3 μm emission from NO observed by the Cryogenic Infrared Radiance Instrumentation for Shuttle (CIRRIS-1A) experiment aboard space shuttle Discovery at 195 km tangent altitude during a strong auroral event is modeled using a first-principles kinetics model. An appropriate SHARC (Strategic High Altitude Radiance Code) Atmospheric Generator (SAG) is dosed with an IBC class III aurora. The spectrally resolved fundamental vibration-rotation band emissions from NO around 5.3 μm resulting from impacts of ambient NO with O as well as reactions of N atoms with O2 are calculated under steady state conditions. The calculated results, using a local translational temperature derived from the observed spectrum, are in excellent agreement with the CIRRIS-1A observations, validating our model. The importance of the accurate nascent vibrational and rotational distribution of chemically produced NO as well as the collisonally induced rotation-to-vibration relaxation of rotationally hot NO is pointed out.

Long-atmospheric-path measurements of near-visible absorption lines of O(2) isotopes and H(2)O with a prototype AlGaAs laser transceiver system.

Abstract: Near-visible absorption lines of ambient H(2)O vapor and normal and heavy isotopes of O(2) have been measured over atmospheric paths of up to 0.46 km by using two wavelength-modulated, line-locked AlGaAs laser sources with a retroreflector-telescope system. The absolute signal levels agree with theoretical calculations for the O(2) isotopes to within 2%, which is similar to the accuracy with which the column densities were known. Measurements of (16)O(2) linewidths and line strengths were made, and they agree with literature values to within experimental error. The detection sensitivity for (16)O(18)O was found to be 0.1 part in 10(6) atm. km, correspondingto an absorbance sensitivity of 1 × 10(-5). It is concluded that atmospheric trace-gas sensing will be feasible with this apparatus over distances of several kilometers and at levels under 1 part in 10(6).

Current assessment of the Red Rectangle band problem

Abstract: In this paper we discuss our insights into several key problems in the identification of the Red Rectangle Bands (RRBs). We have combined three independent sets of observations in order to try to define the constraints guiding the bands. We provide a summary of the general behavior of the bands and review the evidence for a molecular origin of the bands. The extent, composition, and possible absorption effects of the bands are discussed. Comparison spectra of the strongest band obtained at three different spectral resolutions suggests that an intrinsic line width of individual rotational lines can be deduced. Spectroscopic models of several relatively simple molecules were examined in order to investigate where the current data are weak. Suggestions are made for future studies to enhance our understanding of these enigmatic bands.

Bidirectional reflectance distribution function effects in ladar-based reflection tomography

Abstract: Light reflection from a surface is described by the bidirectional reflectance distribution function (BRDF). In this paper, BRDF effects in reflection tomography are studied using modeled range-resolved reflection from well-characterized geometrical surfaces. It is demonstrated that BRDF effects can cause a darkening at the interior boundary of the reconstructed surface analogous to the well-known beam hardening artifact in x-ray transmission computed tomography (CT). This artifact arises from reduced reflection at glancing incidence angles to the surface. It is shown that a purely Lambertian surface without shadowed components is perfectly reconstructed from range-resolved measurements. This result is relevant to newly fabricated carbon nanotube materials. Shadowing is shown to cause crossed streak artifacts similar to limited-angle effects in CT reconstruction. In tomographic reconstruction, these effects can overwhelm highly diffuse components in proximity to specularly reflecting elements. Diffuse components can be recovered by specialized processing, such as reducing glints via thresholded measurements.