Apparatus and methods for launching and receiving a broad wavelength range source
AssigneesAir Liquide America Corporation, Physical Sciences, Inc.
InventorsWilliam A. Von Drasek, David Sonnenfroh, Mark G. Allen, Joy Stafford-Evans
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Abstract
An apparatus and method for simultaneous detection of N gas species through laser radiation attenuation techniques is disclosed. Each of the N species has a spectral absorption band. N laser sources operate at a wavelength λN in a spectral absorption band separated by the cutoff wavelength for single-mode transmission. Each laser source corresponds to a gas species and transmits radiation through an optical fiber constructed and arranged to provide single-mode transmission with minimal power loss.
Claims32
An apparatus for simultaneous detection of X gas species through laser radiation attenuation techniques, where at least one of the X gas species has a spectral absorption band whose wavelength is shorter than the cutoff wavelength for the other spectral absorption band, the apparatus comprising:
- a) N laser sources, wherein each of the N laser sources is adapted to operate at a wavelength λN in a spectral absorption band separated by the cutoff wavelength for single mode transmission, each laser source corresponding to a spectral region for detecting a gas species;
- b) each of the N laser sources adapted to transmit radiation through an optical fiber constructed and arranged to provide single-mode transmission with minimal power loss to a beam splitter, said beam splitter sending a first portion of each of the N laser's radiation to a balanced ratiometric detector, and a second portion to a compound ferrule;
- c) the compound ferrule constructed and arranged so that each single-mode optical fiber terminating therein is held at a separation distance substantially less than a focal length of a collimating optical component to which the N beams are directed by the compound ferrule, the collimating optical component adapted to route N collimated laser beams through a process containing N gas species to be detected;
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- d) means for receiving and detecting nonabsorbed radiation from each laser and creating N outputs for each laser wavelength λN.
A method for simultaneous detection of N gas species through laser radiation attenuation techniques comprising:
- (a) launching N laser wavelengths from N laser sources, wherein each of the N laser sources operates at a wavelength λN in a spectral absorption band, the wavelength λN being separated by a cutoff wavelength for single mode transmission, and each laser source corresponding to a gas species;
- (b) transmitting radiation from each of the N laser sources through an optical fiber, each optical fiber being constructed and arranged to provide single-mode transmission with minimal power loss to a compound ferrule;
- (c) separating each single-mode optical fiber using the compound ferrule thus creating N collimated laser beams;
- (d) routing the N collimated laser beams through a medium having N species to be detected;
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- (e) receiving and detecting radiation corresponding to the N gas species to be detected.
An apparatus for simultaneous detection of N gas species through laser radiation attenuation techniques comprising:
- (a) N laser sources, each of the N laser sources being adapted to operate at a wavelength AN in a spectral absorption band separated by the cutoff wavelength for single mode transmission, each laser source corresponding to a gas species;
- (b) each of the N laser sources adapted to transmit radiation through an optical fiber constructed and arranged to provide single-mode transmission with minimal power loss to N achromat lenses adapted to create N collimated laser beams;
- (c) means for launching the N collimated laser beams into a medium containing the N gas species to be detected;
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- (d) means for receiving and detecting portions of the N collimated laser beams.
A method for simultaneous detection of N gas species through laser radiation attenuation techniques comprising:
- (a) providing N laser sources, wherein each of the N laser sources is adapted to operate at a wavelength λN in a spectral absorption band separated by the cutoff wavelength for single mode transmission, each laser source corresponding to a gas species;
- (b) transmitting each of the wavelengths λN through an optical fiber (preferably dedicated), each optical fiber having single-mode optical fiber characteristics sufficient to insure single-mode transmission with minimal power loss to N achromat lenses, each achromat lens having a proper wavelength-specific anti-reflective coating, the N achromat lenses adapted to create N collimated laser beams;
- (c) launching the N collimated laser beams into the process containing the N gas species to be detected;
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- (d) receiving and detecting nonaborbed portions of the N collimated laser beams.
Dependencies are inferred from the claim text.