Southwest Sciences, Inc.

Avisa Pharma, Inc.

Southern Cross Corporation

Joel A Silver

David S Bomse

Jeffrey S Pilgrim

Mark E Paige

Shin-Juh Chen

Daniel James Kane

David Christian Hovde

Kristen A Peterson

Anthony L Gomez

Steven Michael Massick

David S Joseph

Frank T Petroski, Jr

Sean Durkin

D Christian Hovde

Alan C Stanton

Stanton: Alan C

Steven M Massick

The invention is directed to methods of detecting lung, gastrointestinal tract, and systemic infections by measuringCO/COisotopic ratios of gaseous carbon dioxide in exhaled breath samples of a subject after administration of aC-isotopically-labeled compound.

Methods for detecting bacterial infections

An apparatus and method for monitoring gas velocity, temperature, and pressure in combustion systems and flow devices, in particular at inlets and isolators of scramjet engines. The invention employs wavelength modulation spectroscopy with first harmonic detection and without the need to scan the full absorption spectra.

Fluid properties measurements using wavelength modulation spectroscopy with first harmonic detection

An optical cell and a method of operating an optical cell comprising employing a first mirror comprising a first hole therein at approximately a center of the first mirror and through which laser light enters the cell, employing a second mirror comprising a second hole therein at approximately a center of the second mirror and through which laser light exits the cell, and forming a Lissajous pattern of spots on the mirrors by repeated reflection of laser light entering the cell.

Dense pattern multiple pass cells

The present invention is a portable gas leak detector preferably comprising a portable optical spectroscopy apparatus for measurement of gas concentration.

Portable natural gas leak detector

An optical spectroscopy apparatus and method for measurement of species concentration, number density, or column density comprising emitting light from a laser light source, receiving light via a fixed length optical path from the source and containing a species to be detected, receiving light via a detector at an end of the path, determining one or more of species concentration, number density, and column density via signal processing electronics connected to the detector, and switching between a plurality of operational modes measuring a same absorption feature of the species depending on measured absorbance.

Gas measurement over extreme dynamic range of concentrations

A multiple pass optical cell and method comprising providing a pair of opposed cylindrical mirrors having curved axes with substantially equal focal lengths, positioning an entrance hole for introducing light into the cell and an exit hole for extracting light from the cell, wherein the entrance hole and exit hole are coextensive or non-coextensive, introducing light into the cell through the entrance hole, and extracting light from the cell through the exit hole.

Dense pattern optical multipass cell

An apparatus and method for monitoring oxygen concentrations in fuel tank ullage comprising providing a sensor head comprising an optical cavity, exposing the optical cavity to an ambient gaseous environment of a fuel tank or air separation module, via a laser light source emitting wavelength modulated light through the cavity, and receiving the wavelength modulated light with a detector.

Oxygen sensor for aircraft fuel inerting systems

A multiple pass optical cell and method comprising providing a pair of opposed mirrors, one cylindrical and one spherical, introducing light into the cell via an entrance mechanism, and extracting light from the cell via an exit mechanism, wherein the entrance mechanism and exit mechanism are coextensive or non-coextensive.

Near re-entrant dense pattern optical multipass cell

An absorption spectroscopy method comprising providing a sample in a container, rotating the container, while rotating the container, directing a beam of electromagnetic radiation through the container, the beam comprising one or more wavelengths selected from the group consisting of visible wavelengths, infrared wavelengths, and ultraviolet wavelengths, and measuring characteristics of the beam after it passes through the container. Also an absorption spectroscopy apparatus comprising a container holder, a drive rotating the container holder, means for, while rotating the container, directing a beam of electromagnetic radiation through the container, the beam comprising one or more wavelengths selected from visible wavelengths, infrared wavelengths, and ultraviolet wavelengths, and means for receiving the beam after passage through the container.

Optical absorbance sensitivity and reliability improvement via rotation of sample container

An external cavity laser (and method of generating laser light) comprising: a laser light source; means for collimating light output by the laser light source; a diffraction grating receiving collimated light; a cavity feedback mirror reflecting light received from the diffraction grating back to the diffraction grating; and means for reliably tuning the external cavity laser to discrete wavelengths.

Discrete wavelength-locked external cavity laser

A photoacoustic spectroscopy method and apparatus for maintaining an acoustic source frequency on a sample cell resonance frequency comprising: providing an acoustic source to the sample cell, the acoustic source having a source frequency; repeatedly and continuously sweeping the source frequency across the resonance frequency at a sweep rate; and employing an odd-harmonic of the source frequency sweep rate to maintain the source frequency sweep centered on the resonance frequency.

Acoustic resonance frequency locked photoacoustic spectrometer

A photoacoustic spectroscopy method and apparatus for maintaining an acoustic source frequency on a sample cell resonance frequency comprising: providing an acoustic source to the sample cell to generate a photoacoustic signal, the acoustic source having a source frequency; continuously measuring detection phase of the photoacoustic signal with respect to source frequency or a harmonic thereof; and employing the measured detection phase to provide magnitude and direction for correcting the source frequency to the resonance frequency.

Acoustic resonance phase locked photoacoustic spectrometer

A method and apparatus for demodulating a plurality of frequency components output from a photodetector in a wavelength modulation spectroscopy system and determining absorption line shapes from the demodulated data. Demodulation is performed with a homodyne demodulator. Line center magnitudes of selected even harmonics of the demodulated output frequency components are measured and the absorption line shape is calculated from the relationship between these magnitudes.

Wavelength modulation spectroscopy with multiple harmonic detection

Disclosed are a method and apparatus for dual modulation of an optical spectroscopy laser. Demodulation is accomplished in a manner resulting in measurement of absorbance of a gas species, as well as stabilization of laser wavelength and baseline noise reduction.

Dual modulation laser line-locking technique for wavelength modulation spectroscopy

An improvement to a dual-modulation line-locking device for wavelength modulation spectroscopy employing a lowpass filter to generate a nonnormalized error signal and a bandpass filter and RMS-to-DC converter to generate a centering signal. When the error signal is approximately zero and the centering signal is large, the wavelength is coincident with the center of the absorption feature of the sample.

Growing community of inventors

Santa Fe, NM, United States of America

Joel A Silver