Optical oxygen concentration monitor
Abstract
A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen`s A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2,000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of themore »
- Inventors:
- Issue Date:
- Research Org.:
- Aerodyne Research, Inc
- Sponsoring Org.:
- USDOE, Washington, DC (United States)
- OSTI Identifier:
- 516940
- Patent Number(s):
- 5650845
- Application Number:
- PAN: 8-444,820
- Assignee:
- Aerodyne Research, Billerica, MA (United States)
- DOE Contract Number:
- FG02-93ER81522
- Resource Type:
- Patent
- Resource Relation:
- Other Information: PBD: 22 Jul 1997
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 44 INSTRUMENTATION, INCLUDING NUCLEAR AND PARTICLE DETECTORS; MONITORS; OXYGEN; OPTICAL SYSTEMS; LIGHT SOURCES; MEASURING METHODS; DESIGN; ABSORPTION SPECTRA; CONCENTRATION RATIO
Citation Formats
Kebabian, P. Optical oxygen concentration monitor. United States: N. p., 1997.
Web.
Kebabian, P. Optical oxygen concentration monitor. United States.
Kebabian, P. Tue .
"Optical oxygen concentration monitor". United States.
@article{osti_516940,
title = {Optical oxygen concentration monitor},
author = {Kebabian, P},
abstractNote = {A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen`s A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2,000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest. 4 figs.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1997},
month = {7}
}