Ultra narrow band fiber optic Bragg grating filters for atmospheric water vapor measurements

Persistent Link:
http://hdl.handle.net/10150/280456
Title:
Ultra narrow band fiber optic Bragg grating filters for atmospheric water vapor measurements
Author:
Vann, Lelia Belle
Issue Date:
2003
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Optical fibers have revolutionized telecommunications. Much of the success of optical fiber lies in its near-ideal properties: low transmission loss, high optical damage threshold, and low optical nonlinearity. The photosensitivity of an optical fiber was accidentally discovered by Hill, et al. in 1978. However, the technological advances made in the field of photosensitive optical fibers are relatively recent. This fascinating technology of photosensitive fiber is based on the principle of a simple in-line all-fiber optical filter. It has been shown that the transmission spectrum of a fiber Bragg grating can be tailored by incorporating multiple phase-shift regions during the fabrication process. Phase shifts open up ultra narrowband transmission windows inside the stop band of the Bragg grating. As a specific application, this research is focused on applying this technology in future space-based water vapor DIfferential Absorption LIDAR (DIAL) systems to improve the performance of space-based LIDAR systems by rejecting the reflected solar background. The primary goal of this research effort was to demonstrate the feasibility of using ultra narrow band fiber optic Bragg grating filters for atmospheric water vapor measurements. Fiber Bragg gratings were fabricated such that two transmission filter peaks occurred and were tunable, one peak at a 946 nm water vapor absorption line and another peak at a region of no absorption. Both transmission peaks were in the middle of a 2.66-nm stop band. Experimental demonstration of both pressure and temperature tuning was achieved and characterization of the performance of several custom-made optical fiber Bragg grating filters was made. To our knowledge these are the first optical fiber gratings made in this frequency range and for this application. The bandwidth and efficiency of these filters were measured and then these measurements were compared with theoretical calculations using a piecewise matrix form of the coupled-mode equation. Finally, an ultra narrow band water vapor DIAL filter was characterized having two pass bands less than 8 pm and peak transmissions greater than 80 percent. Such fiber optic filters are now ready for integrating into space-based water vapor LIDAR systems. More broadly, these filters have the characteristics that will revolutionized satellite remote-sensing.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Physics, Atmospheric Science.; Physics, Optics.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Atmospheric Sciences
Degree Grantor:
University of Arizona
Advisor:
Herman, Benjamin M.

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleUltra narrow band fiber optic Bragg grating filters for atmospheric water vapor measurementsen_US
dc.creatorVann, Lelia Belleen_US
dc.contributor.authorVann, Lelia Belleen_US
dc.date.issued2003en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractOptical fibers have revolutionized telecommunications. Much of the success of optical fiber lies in its near-ideal properties: low transmission loss, high optical damage threshold, and low optical nonlinearity. The photosensitivity of an optical fiber was accidentally discovered by Hill, et al. in 1978. However, the technological advances made in the field of photosensitive optical fibers are relatively recent. This fascinating technology of photosensitive fiber is based on the principle of a simple in-line all-fiber optical filter. It has been shown that the transmission spectrum of a fiber Bragg grating can be tailored by incorporating multiple phase-shift regions during the fabrication process. Phase shifts open up ultra narrowband transmission windows inside the stop band of the Bragg grating. As a specific application, this research is focused on applying this technology in future space-based water vapor DIfferential Absorption LIDAR (DIAL) systems to improve the performance of space-based LIDAR systems by rejecting the reflected solar background. The primary goal of this research effort was to demonstrate the feasibility of using ultra narrow band fiber optic Bragg grating filters for atmospheric water vapor measurements. Fiber Bragg gratings were fabricated such that two transmission filter peaks occurred and were tunable, one peak at a 946 nm water vapor absorption line and another peak at a region of no absorption. Both transmission peaks were in the middle of a 2.66-nm stop band. Experimental demonstration of both pressure and temperature tuning was achieved and characterization of the performance of several custom-made optical fiber Bragg grating filters was made. To our knowledge these are the first optical fiber gratings made in this frequency range and for this application. The bandwidth and efficiency of these filters were measured and then these measurements were compared with theoretical calculations using a piecewise matrix form of the coupled-mode equation. Finally, an ultra narrow band water vapor DIAL filter was characterized having two pass bands less than 8 pm and peak transmissions greater than 80 percent. Such fiber optic filters are now ready for integrating into space-based water vapor LIDAR systems. More broadly, these filters have the characteristics that will revolutionized satellite remote-sensing.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectPhysics, Atmospheric Science.en_US
dc.subjectPhysics, Optics.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineAtmospheric Sciencesen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorHerman, Benjamin M.en_US
dc.identifier.proquest3108963en_US
dc.identifier.bibrecord.b44831079en_US
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