University of Colorado

Government of the United States of America, as Represented by the Secretary of Commerce

US Government as Represented by the Secretary of the Army

Robert James Wright

Gregory Brian Rieker

Caroline B Alden

Sean C Coburn

Kuldeep Prasad

Hugh R Carlon

David V Kimball

A frequency-measurement method uses a dual frequency-comb spectrometer as an optical wavemeter to measure the frequency of a reference laser that is used to frequency-stabilize the spectrometer. The method includes measuring a walking rate of center bursts in a sequence of interferograms recorded by the spectrometer, determining a number of teeth in each of a plurality of Nyquist windows formed by the dual frequency-comb spectrometer, and determining a Nyquist number of the one Nyquist window covering the laser frequency. The reference laser frequency can then be determined from the number of teeth in each Nyquist window, the Nyquist number, and the comb spacing of either one of the two frequency combs of the dual frequency-comb spectrometer. The reference laser frequency does not need to be measured with a separate wavemeter, or calibrated with respect to a known atomic or molecular transition.

Systems and methods for dual comb spectroscopy

A system for detecting gas leaks and determining their location and size. A data gathering portion of the system utilizes a chosen geometrical configuration to collect path-integrated spectroscopic data over multiple paths around an area. A processing portion of the system applies a transport model together with meteorological data of the area to generate an influence function of possible leak locations on gas detector measurement paths, and applies an inversion model to the influence function, prior data, and the spectroscopic data to generate gas source size and location.

Apparatus and methods for location and sizing of trace gas sources

A process for determining a location and size of a gas source within an area with a spectrometer gas monitor includes: providing the spectrometer gas monitor; performing fence line monitoring of the area with the spectrometer gas monitor; collecting spectroscopic data over multiple open paths around the area with the spectrometer gas monitor; measuring atmospheric conditions along gas inflows and gas outflows of the area; subtracting a background for a selected gas from the spectroscopic data; applying a boundary constraint to the spectroscopic data; determining an atmospheric concentration of air entering the area; applying bootstrapping to the spectroscopic data; applying zero minimum elimination to the spectroscopic data; and producing inversion data from the spectroscopic data to determine the location and size of the gas source within the area.

Determining a location and size of a gas source with a spectrometer gas monitor

An electrooptical system and technique for direct quantitative measurement of the mass concentration of monodisperse aerosols by means of filling an enclosed chamber with a cloud or a sequence of separate clouds of essentially transparent and spherical, aerosolized particles or droplets of known density and known or selectively controlled particle size. While within the confines of the chamber the cloud, or each of the sequence of clouds, of aerosolized particles is maintained in a homogeneous condition and irradiated with a beam of high-intensity and constant wavelength irradiation selected to possess a wavelength to particle size ratio wherein attenuation of the irradiation will be almost exclusively, if not nearly entirely, attributable to optical scattering. The mass concentration of the cloud, or each of the sequence of clouds, of aerosolized particles is directly and quantitatively measured, or monitored, as a direct function of the measured magnitude, or intensity, of the attenuated beam of irradiation transmitted through the cloud. The results provide a reliably accurate measurement to within a minimal margin of error of .+-.10% or less. The system and technique provide a relatively quick and inexpensive means and procedure for calibrating the accuracy, or efficiency of various types of aerosol sampling devices and equipment by affording a chamber from which a known volume of the cloud of monodisperse aerosolized particles may be aspirated into the sampling device or equipment while electrooptically measured. The measured results attained by use of the sampling device may then be compared for accuracy purposes with the electrooptically measured results.

Growing community of inventors

Boulder, CO, United States of America

Robert James Wright