Accession Number : ADD015156
Title : High Optical Density Measuring Spectrometer.
Descriptive Note : Patent, filed 29 Sep 89, patented 24 Sep 91,
Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC
Personal Author(s) : Welch, Jeanne A
Report Date : 24 Sep 1991
Pagination or Media Count : 7
Abstract : An apparatus is disclosed for measuring the spectra of a high optical density sample having substantially known optical properties. In a preferred embodiment, the apparatus comprises: a laser for producing a light beam; and Raman cell responsive to the light beam for generating a first light containing a plurality of preselected wavelength components; an optical system for directing the first light through the sample; a dispersion device for spatially separating the first light passed through the sample into its plurality of preselected wavelength components; a plurality of light detectors positioned to respectively receive the spatially-separated preselected components into a plurality of associated photocurrents having amplitudes respectively representative of the numbers of photons in the spatially-separated preselected wavelength components; and a photon counter for respectively converting the plurality of associated photocurrents into a plurality of photon counts corresponding to the transmittance of the sample at the respective preselected wavelength components of the first light passing through the sample.
Descriptors : CELLS, COUNTING METHODS, DETECTORS, DISPERSING, ELECTRIC CURRENT, FREQUENCY, HIGH DENSITY, LASERS, LIGHT, NUMBERS, OPTICAL EQUIPMENT, OPTICAL PROPERTIES, PHOTOELECTRICITY, PHOTONS, RAMAN SPECTROSCOPY, TRANSMITTANCE
Subject Categories : Test Facilities, Equipment and Methods
Distribution Statement : APPROVED FOR PUBLIC RELEASE