Dissertations / Theses: 'Fiber optics'

1

Richmond, Eric William. "Birefringent single-arm fiber optic enthalpimeter for catalytic reaction monitoring." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-07282008-135248/.

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2

Kuhlmey, Boris T. "Theoretical and numerical investigation of the physics of microstructured optical fibres." Connect to full text, 2004. http://setis.library.usyd.edu.au/adt/public_html/adt-NU/public/adt-NU20040715.171105.

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Thesis (Ph. D.)--School of Physics, Faculty of Science, University of Sydney, 2004. (In conjunction with: Université de Droit, d'Économie et des Sciences d'Aix-Marseille (Aix Marseille III)).
Bibliography: leaves 196-204.

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3

Paye, Corey. "An Analysis of W-fibers and W-type Fiber Polarizers." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/32474.

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Optical fibers provide the means for transmitting large amounts of data from one place to another and are used in high precision sensors. It is important to have a good understanding of the fundamental properties of these devices to continue to improve their applications. A specially type of optical fiber known as a W-fiber has some desirable properties and unique characteristics not found in matched-cladding fibers. A properly designed W- fiber supports a fundamental mode with a finite cutoff wavelength. At discrete wavelengths longer than cutoff, the fundamental mode experiences large amounts of loss. The mechanism for loss can be described in terms of interaction between the fiberâ ¢s supermodes and the lossy interface at the fiberâ ¢s surface. Experiments and computer simulations support this model of W-fibers. The property of a finite cutoff wavelength can be used to develop various fiber devices. Under consideration here is the fiber polarizer. The fiber polarizer produces an output that is linearly polarized along one of the fiberâ ¢s principal axes. Some of the polarizer properties can be understood from the study of W-fibers.
Master of Science

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4

Greaves, James David. "Numerical analysis of the outside vapor deposition process." Ohio : Ohio University, 1990. http://www.ohiolink.edu/etd/view.cgi?ohiou1183491109.

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5

Haskell, Adam Benjamin. "A Durability and Utility Analysis of EFPI Fiber Optic Strain Sensors Embedded in Composite Materials for Structural Health Monitoring." Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/HaskellAB2006.pdf.

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6

Srinivas, K. T. "Axial strain effects on optical fiber mode patterns." Thesis, This resource online, 1987. http://scholar.lib.vt.edu/theses/available/etd-04122010-083554/.

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7

Lyyttkäinen, Katja Johanna. "Control of complex structural geometry in optical fibre drawing /." Connect to full text, 2004. http://setis.library.usyd.edu.au/adt/public_html/adt-NU/public/adt-NU20041011.120247.

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Lyytikäinen, Katja Johanna. "Control of complex structural geometry in optical fibre drawing." Connect to full text, 2004. http://hdl.handle.net/2123/597.

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Thesis (Ph. D.)--University of Sydney, 2004.
Title from title screen (viewed 14 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Physics, Faculty of Science. Includes bibliographical references. Also available in print form.

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9

Washburn, Brian Richard. "Dispersion and nonlinearities associated with supercontinuum generation in microstructure fibers." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/30964.

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10

Derrington, Dolores Cormack. "Overview of fiber optics technology: industrial and military." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/43896.

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Fiber optics technology is being used in many applications, both in the military world and in the industrial world. A broad overview of this technology is provided, including a discussion of the fundamentals of fiber operation and component characteristics. Applications of fiber optics in both military and industrial communities is addressed, identifying specific examples in both cases. In addition, market projections and technology trends are discussed for both the military and industrial communities.
Master of Science

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11

Hao, Miin-Jong. "Performance evaluation of practival FSK, CPFSK, and ASK detection schemes for coherent optical fiber communication systems." Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/15686.

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12

Lee, Shiao-Chiu. "Axial offset effects upon optical fiber sensor and splice performance." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/91128.

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A kind of intensity modulated fiber sensor utilizing axial offset parameter is proposed. The theoretical analysis and experimental characteristics of this sensor are described. All the theoretical results derived in this thesis are based on assuming a uniform power distribution in the fibers. An expression of coupling efficiency of central dipped parabolic graded index fibers due to axial offset is derived. The results show less sensitivity to axial offset for the central dipped fibers than for the parabolic profile fibers without a dip. Expressions of coupling efficiency of graded index fibers due to axial offset for several different values of a are also derived. The results show that sensitivity increases as the value of a decreases. A general expression of coupling efficiency which is valid for small values of axial offset is derived. This expression exhibits a linear relationship between coupling efficiency and small axial offset. Coupling efficiencies versus fiber end separation and axial offset of step index fibers have been measured. The measurements show that coupling efficiency is much more sensitive to axial offset than end separation. A simple construction of the axial offset fiber sensor is described. An approximate linear relationship between the output power and the mechanical loading has been obtained for this sensor. Several ways of increasing the sensitivity of this sensor are discussed.
M.S.

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13

Churin, Dmitriy. "Development of Ultrafast Fiber Laser Sources." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/579113.

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The development of high average and peak power ultrashort pulsed fiber lasers is important for many critical research, industrial, and defense applications. However, the performance of mode-locked fiber oscillators still lags behind that of solid-state counterparts such as Kerr-lens mode-locked Ti:sapphire lasers. Despite the drawbacks in cost, size and required maintenance, Ti:sapphire remains the workhorse of ultrafast science. One of the remaining challenges for fiber lasers to overcome is their limited set of accessible wavelengths. Unfortunately, readily available ytterbium, erbium and thulium fiber lasers can produce coherent radiation only near 1, 1.55 and 2μm, respectively. There remain a significant number of wavelength regions that fiber lasers cannot address. In this thesis, novel fiber lasers producing ultrashort pulses at wavelengths not currently accessible with established active rare-earth-doped fibers are investigated. Our main approach is to use various nonlinear optical effects to generate new laser wavelengths. First, a watt-level synchronously pumped Raman fiber oscillator generating tens of nanojoules femtosecond pulses is demonstrated. Stimulated Raman scattering in a passive fiber within an oscillator cavity allows formation of Raman pulses that are spectrally redshifted with respect to the pump pulses. World-record output pulse energy and conversion efficiency have been achieved with our femtosecond Raman fiber laser design. We have also demonstrated a high power, widely tunable all-fiber optical parametric oscillator (FOPO) based on four-wave mixing in a passive fiber. The FOPO is synchronously pumped with an Yb³⁺-doped mode-locked fiber laser working at ~1040nm. The FOPO produces ultrashort pulses tunable from 760 to 1560nm. Record pulse energy is generated at the output of the femtosecond FOPO. Depending on the configuration of the FOPO, the duration of produced pulses varies between 170fs and 3ps. This new laser source has similar performance to standard Ti:sa femtosecond lasers so it can potentially replace the latter in many applications. Ultrashort optical pulses in the mid-IR and long-IR range (2-20 μm) have many important applications in gas sensing, counter-measures, etc. The realization of the ultrashort pulses in the mid-IR and long-IR wavelengths requires the use of free-space nonlinear crystals. An efficient mid-IR source based on difference frequency generation (DFG) in an AgGaS₂ crystal using femtosecond erbium/thulium pump fiber laser has been proposed and demonstrated. The photon conversion efficiency of the pump wave (1.55μm) to idler wave (9.2μm) has been measured to be 16%, which is today a record for conversion of near-IR light radiation from fiber lasers to 9μm spectral range. Potentially the photon conversion efficiency can be increased up to 60% by using pump pulses having higher peak power. Finally, generation of supercontinuum (SC) light in the mid-IR spectral range is also demonstrated. It is well known that SC produced in standard optical fibers is limited to ~6μm by material absorption. The liquid core optical fiber platform has been proposed to address this matter. Several highly nonlinear liquids have minimal absorption in the mid-IR wavelength range, which potentially allows us to create broadband SC light in this spectral region. SC generation up to 2.4μm in an integrated hollow core optical fiber filled with CS₂ has been demonstrated. Further development of the liquid core optical fiber platform should allow generation of the SC covering wavelengths beyond 6μm.

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14

Smith, Kevin H. "In-fiber Optical Devices Based on D-fiber." BYU ScholarsArchive, 2005. https://scholarsarchive.byu.edu/etd/291.

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This dissertation presents the fabrication and analysis of in-fiber devices based on elliptical core D-shaped optical fiber. Devices created inside optical fibers are attractive for a variety of reasons including low loss, high efficiency, self-alignment, light weight, multiplexibility, and resistance to electromagnetic interference. This work details how D-fiber can be used as a platform for a variety of devices and describes the creation and performance of two of these devices: an in-fiber polymer waveguide and a surface relief fiber Bragg grating. In D-fiber the core is very close to the flat side of the ‘D’ shape. This proximity allows access to the fields in the fiber core by removal of the cladding above the core. The D-fiber we use also has an elliptical core, allowing for the creation of polarimetric devices. This work describes two different etch processes using hydrofluoric acid (HF) to remove the fiber cladding and core. For the creation of devices in the fiber core, the core is partially removed and replaced with another material possessing the required optical properties. For devices which interact with the evanescent field, cladding removal is terminated before acid breaches the core. Etching fibers prepares them for use in the creation of in-fiber devices. Materials are placed into the groove left when the core of a fiber is partially removed to form a hybrid waveguide in which light is guided by both the leftover core and the inserted material. These in-fiber polymer waveguides have insertion loss less than 2 dB and can potentially be the basis for a number of electro-optic devices or sensors. A polarimetric temperature sensor demonstrates the feasibility of the core replacement method. This work also describes the creation of a surface relief fiber Bragg gratings (SR-FBGs) in the cladding above the core of the fiber. Because it is etched into the surface topography of the fiber, a SR-FBG can operate at much higher temperatures than a standard FBG, up to at least 1100 degrees Celsius. The performance of a SR-FBG is demonstrated in temperature sensing at high temperatures, and as a strain sensor.

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15

Robinson, Risa J. "Polarization modulation and splicing techniques for stressed birefringent fiber /." Online version of thesis, 1995. http://hdl.handle.net/1850/12228.

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16

Battiato, James Michael 1966. "Fiber Bragg gratings." Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/288905.

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The properties of fiber Bragg gratings are investigated theoretically and experimentally. The effects of experimental parameters on grating characteristics are modeled for both uniform and non-uniform gratings. Particular emphasis is placed on the formation of fiber Bragg gratings tilted at 45 degrees with respect to the fiber axis in single mode fibers. In this case, light is coupled out of the fiber in a surface normal manner. Several fabrication methods for producing tilted fiber gratings are explored and characterized. The most efficient gratings are obtained with a prism coupling technique. Experimental tilted grating performance is shown to be in good agreement with the predictions of a two-dimensional coupled mode theory. Fiber gratings are also used to demonstrate an Er/Nd co-doped fiber laser. This dual wavelength laser is formed with a common cavity and common gain medium.

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17

Utou, Frumence E. "Fiber optic sensors ensuring structural integrity." Thesis, Cape Peninsula University of Technology, 2005. http://hdl.handle.net/20.500.11838/1300.

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Thesis (DTech (Mechnical Engineering))--Cape Peninsula University of Technology, 2005
Among the issues that are taken into consideration for many years by Engineers and Technologists is the integrity of the servicing elements in structures and mechanisms. It is a documented phenomenon that after a certain period of time, in service, engineering components tend to change their original state, and begin to develop faults and defects. This includes the original shape distortion due to effects such as bending, twisting, and cracks. The above-sited effects may be caused by the sudden or accumulative effect of overloading, thermal shocks, corrosion etc, which eventually lead to malfunction of these engineering components. The occurrence of the cracks may be as a result of stress variation in excess of different or similar materials; thermal shocks, vibration, etc. A system of structural health monitoring using optical fiber sensors to track down a crack occurrence and its propagation is considered to be a promising method in warning of catastrophic events. Taking advantage of optical fibers' properties and behavior, such as easy interaction with other materials, small size, low weight, corrosion resistance, geometrical flexibility and an inherent immunity to electromagnetic interference, there is potential in adopting the Fiber Optic Sensors (FOS) for structural health monitoring systems. Structural integrity does not confine itself to crack detection only. For example there are many instances where unwanted or excessive displacement may occur. Optical fibers play an important role in proximity sensing as evidenced in the literature [49] to [54] and available commercial systems. However it is felt that FOS displacement sensors may suffer in measurement accuracy due to in situ conditions.

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18

Jackson, James Trent. "Reduction of EDFA optical power transients using power shaping." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/jackson/JacksonJ0808.pdf.

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Many erbium doped fiber amplifier (EDFA) based multi-wavelength optical networks employ techniques such as burst-switching or packet switching where the time interval between traffic blocks can be long enough to induce EDFA optical power transients. The optical power transients are created by abrupt changes in the average input power to the EDFAs and can adversely affect the performance of the network. To mitigate the effects of EDFA optical power transients on optical networks, a method called power shaping where heads and tails are joined to the beginning and end of a traffic block is investigated. A head (tail) gradually increases (decreases) the channel power by employing a bit sequence in which the probability of a \"1\" (\"0\") increases from 0 to 0.5. Theoretical and experimental results both show that EDFA optical power transients can be significantly reduced with adequate shaping periods. Experiments also show the bit error rate of the system is reduced for increased shaping periods. Power shaping is an economical means of suppressing EDFA optical power transients compared to other physical layer approaches that require the addition of specialized components and can be applied to EDFAs as well as other solid-state and Raman optical amplifiers.

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19

Hattori, Haroldo Takashi. "Low Nonlinearity Optical Fibers for Broadband and Long-Distance Communications." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/29816.

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A class of low nonlinearity dispersion-shifted and dispersion-flattened fibers for broadband and long haul applications is presented. The refractive index profiles of these fibers assume a depressed-core multi-clad geometry in order to achieve effective-areas much larger than those in conventional optical fibers. A systematic approach for designing large effective-area dispersion-shifted fibers, using a reference W-index profile to initiate the design, is presented. Transmission properties, including effective-area, mode-field-diameter, dispersion, dispersion slope, cutoff wavelength, and bending, microbending and splice losses are evaluated for several design examples. To ascertain that the proposed fibers can be practically fabricated, the effects of varying fiber dimensions and indices on effective-area, mode-field-diameter and dispersion are assessed. It is shown that there is a trade-off between effective-area and mode-field-diameter and, generally, larger effective-areas are associated with larger mode-field-diameters. In other words, less signal distortion due to fiber nonlinearity (larger effective-area) is associated with higher power loss due to bending of fiber (larger mode-field-diameter). Thus, a large effective-area and low bending loss are conflicting requirements. A parameter Q is defined as a performance indicator, considering effective-area and mode-field-diameter. Dispersion-shifted single-mode fiber designs with effective-areas of 78 mm 2 to 210 mm2 and the corresponding mode-field-diameter of 8.94 mm to 14.94 mm, dispersion less than 0.07 ps/nm.km, and dispersion slope of about 0.05 ps/ nm2.km are presented. Numerical simulations for propagation of pulses in few designed fibers are performed.Designs of large effective-area dispersion-flattened fibers are also presented, for the first time we believe. These fibers provide large effective-area and low dispersion over an extended range of wavelengths. For our design, over the wavelength range of 1.48 mm < l < 1.58 mm, the effective-area is 75 mm2 to 100 mm2, while the dispersion remains below 0.7 ps/nm.km.
Ph. D.

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20

Jong, Yeung-dong. "Fiber-optic interferometer for high 1/f noise environments /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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21

Flatten, Amy K. "Interaction of ultrasound with a polarization preserving optic fiber." Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/30723.

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22

Fan, Chenjun. "Fiber optic sensor based on dual ring resonator system /." Online version of thesis, 1992. http://hdl.handle.net/1850/11070.

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23

Davis, Donald D. Jr. "Long-period fiber gratings fabricated with focused CO₂ laser pulses." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/15764.

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24

Gao, Song. "Fabrication of Tapered Dual-core As2Se3-PMMA Fiber and Its Applications." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38697.

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Fiber optical temperature and strain sensors have been extensively investigated for applications in the civil structures to ensure safety and prevent disasters in advance. Most of the demonstrated fiber sensors are based on the silica fibers to form an interferometer by measuring the spectrum wavelength shift caused by the change of the refractive index and fiber length, and the sensitivities, defined as the rate of wavelength shift with respect to temperature or strain, are limited by the small values of thermal-expansion coefficient and thermo-optic effect of the silica materials. To improve the sensitivity, we designed the dual-core As2Se3-PMMA fiber with the PMMA cladding diameter 56.5 times larger than that of the As2Se3 cores, which brings out many interesting sensing applications. Nonlinear devices have a variety of practical applications including parametric amplification, all-optical switching, super-continuum generation, and sensing applications. Tapered chalcogenide-polymer fiber structures composed of an As2Se3 core and a polymethyl methacrylate (PMMA) cladding are a promising platform for nonlinear applications because the As2Se3 core provides high nonlinearity over the near- and mid-infrared spectral ranges for compact nonlinear devices with low power consumption and the PMMA cladding provides high mechanical strength for easy handling. Advanced As2Se3-PMMA fiber structures such as dual-core fibers that support guided propagation of an even mode and an odd mode will open the way for a variety of novel devices in the near- and mid-IR wavelength range. In my work I utilized two As2Se3 fibers and a polymethyl methacrylate (PMMA) tube for the fabrication of dual-core As2Se3-PMMA tapers and demonstration of the sensing applications and nonlinear optical effects. The thesis mainly consists of three parts: the fabrication process, the sensing applications, and the nonlinear applications in the tapered dual-core As2Se3-PMMA fiber. In the first part, the fabrication process of the tapered dual-core As2Se3-PMMA fiber is introduced. The dual-core As2Se3-PMMA fibers are fabricated using a rod-in-tube method. The images of the setups and fibers in process are listed. In the second part, a theoretical model for temperature and strain measurement and four sensing applications are introduced. Firstly, we demonstrate an approach for high-sensitivity simultaneous temperature and strain measurement in a dual-core As2Se3-PMMA taper with As2Se3 core diameter of 0.55 μm. High measurement sensitivities are observed for both principal polarization axes of the tapered dual-core As2Se3-PMMA fiber with temperature sensitivities of -115 pm/ºC for axis-1, -35.5 pm/ºC for axis-2, and strain sensitivities of -4.21 pm/με for axis-1 and -3.16 pm/με for axis-2. Secondly, the thermal forces in a dual-core As2Se3-PMMA taper are investigated. A temperature-insensitive strain sensor is proposed and demonstrated based on the thermal forces. Finally, two approaches for temperature and strain sensitivity enhancement are investigated. The first approach is by reducing the value of the variation of the difference between phases of the even and odd modes with respect to wavelength (∂ϕd(λ)/∂λ) and increasing thermal-forces in a dual-core As2Se3-PMMA taper with As2Se3 core diameter of 2.5 μm. The value of ∂ϕd(λ)/∂λ decreases with the As2Se3 core diameter and thermal-forces on the As2Se3 cores are enhanced in the fibers with large PMMA cladding, which work together to enhance the measurement sensitivity. The second approach is based on effective group-velocity matching between the even and odd modes of a dual-core As2Se3-PMMA taper on which an antisymmetric long-period grating is inscribed. The variation of the difference between phases of the even and odd modes with respect to wavelength tends to 0 (∂ϕd(λ)/∂λ→0) near the resonance wavelength of the grating due to the effective group-velocity matching between the two modes, and consequently, thermally-induced change of the difference between phases of the two modes ϕd (λ) leads to a large wavelength shift indicating enhancement of the temperature measurement sensitivity. In the third part, I study the nonlinear optical effects in the hybrid fibers. Firstly, I demonstrate modulation instability within the normal-dispersion regime in a dual-core As2Se3-PMMA fiber. Then I review the work about the forward stimulated Brillouin scattering and its sensing applications. The radial and torsional-radial guided acoustic modes of silica fibers and tapered dual-core As2Se3-PMMA fibers are investigated experimentally and the preliminary results are presented.

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25

Edwards, Gary. "Local area networks with fiber optics." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/28334.

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26

Harris, Bryan William. "Fiber Optics for Flight Control Systems." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1418340523.

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27

Nagarajan, Anjana. "Chemical sensing applications of fiber optics." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07102009-040555/.

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28

Andrews, Jeffrey Pratt. "Longitudinal misalignment based strain sensor." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/43283.

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A practical fiber optic strain sensor has been developed to measure strains in the range of 0.0 to 2.0 percent strain with a resolution ranging between 10 and 100 microstrain depending on sensor design choices. This intensity based sensor measures strain by monitoring strain induced longitudinal misalignment in a novel fiber interconnection. This interconnection is created by aligning fibers within a segment of hollow core fiber. Related splice loss mechanisms are investigated for their effect on resolution. The effect of gauge length and launch conditions are also investigated.

Master of Science

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29

Hardy, Luke Allen. "Improving Thulium Fiber Laser Lithotripsy Efficiency." Thesis, The University of North Carolina at Charlotte, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10936977.

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Kidney stone disease affects approximately 10% of the U.S. population. Conventional Holmium:YAG infrared laser lithotripsy is a standard minimally invasive treatment that operates based on a photothermal interaction with the main chromophore in tissue being water.

Our laboratory is exploring the Thulium Fiber laser (TFL) as an alternative to Ho:YAG laser for lithotripsy, due to the TFL’s ability to operate at low pulse energies and high pulse rates, producing smaller stone fragments and reduced retropulsion. The TFL also more closely matches a high temperature water absorption peak. Additionally, the improved TFL spatial beam profile enables coupling of laser energy into smaller fibers (50-150-µm-core) than currently used in Ho:YAG lithotripsy.

TFL ablation rate, ablation threshold, operation time, and vapor bubble dynamics and pressure transients were analyzed and compared to the Ho:YAG laser in all experiments.

TFL ablation rate was examined at pulse rates up to 500 Hz. Ablation rates scaled linearly with pulse rate and were more effective at higher pulse rates. TFL operation time and ablation rates were found to be more efficient than for Ho:YAG. TFL vapor bubbles were discovered to collapse multiple times along the optical axis of the fiber, while the Ho:YAG laser created a single, larger, bubble that collapsed only once. Due in part to these differing bubble dynamics, lower pressures were observed with the TFL.

Every experiment was designed to examine the TFL ablation mechanisms and find optimum laser parameters to safely increase stone ablation rates and efficiency.

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30

Wu, Shun. "Direct fiber laser frequency comb stabilization via single tooth saturated absorption spectroscopy in hollow-core fiber." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/18373.

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Doctor of Philosophy
Department of Physics
Kristan L. Corwin
Portable frequency references are crucial for many practical on-site applications, for example, the Global Position System (GPS) navigation, optical communications, and remote sensing. Fiber laser optical frequency combs are a strong candidate for portable reference systems. However, the conventional way of locking the comb repetition rate, frep, to an RF reference leads to large multiplied RF instabilities in the optical frequency domain. By stabilizing a comb directly to an optical reference, the comb stability can potentially be enhanced by four orders of magnitude. The main goal of this thesis is to develop techniques for directly referencing optical frequency combs to optical references toward an all-fiber geometry. A big challenge for direct fiber comb spectroscopy is the low comb power. With an 89 MHz fiber ring laser, we are able to optically amplify a single comb tooth from nW to mW (by a factor of 10^6) by building multiple filtering and amplification stages, while preserving the comb signal-to-noise ratio. This amplified comb tooth is directly stabilized to an optical transition of acetylene at ~ 1539.4 nm via a saturated absorption technique, while the carrier-envelope offset frequency, f0, is locked to an RF reference. The comb stability is studied by comparing to a single wavelength (or CW) reference at 1532.8 nm. Our result shows a short term instability of 6 x10^(-12) at 100 ms gate time, which is over an order of magnitude better than that of a GPS-disciplined Rb clock. This implies that our optically-referenced comb is a suitable candidate for a high precision portable reference. In addition, the direct comb spectroscopy technique we have developed opens many new possibilities in precision spectroscopy for low power, low repetition rate fiber lasers. For single tooth isolation, a novel cross-VIPA (cross-virtually imaged phase array) spectrometer is proposed, with a high spectral resolution of 730 MHz based on our simulations. In addition, the noise dynamics for a free space Cr:forsterite-laser-based frequency comb are explored, to explain the significant f0 linewidth narrowing with knife insertion into the intracavity beam. A theoretical model is used to interpret this f0 narrowing phenomenon, but some unanswered questions still remain.

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Ireeta, Winston Tumps. "Aerial optical fibres in telecommunication systems : SOP and PMD monitoring, and tolerance of modulation formats." Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1478.

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The topic of this thesis is aerial optical fibres in telecommunication systems: state of polarization (SOP) and polarization mode dispersion (PMD) monitoring and tolerance of modulation formats. Errors in optical fibre telecommunication systems are introduced when these polarization effects (SOP and PMD) change. These changes are so intense especially in aerial optical fibres. Part of the backbone of South Africa’s national grid includes long distances of aerial optical fibre between transmission exchange stations. The work in this thesis can be divided into three parts which all deal with the major aspects of PMD in deployed aerial optical fibres: characterization, environmental effects plus other perturbations, and tolerance of different modulation formats. In our work, SOP and PMD field measurements revealed that they both fluctuate more rapidly in deployed aerial optical fibres especially on windy and hot days. The SOP and PMD changes in the aerial optical fibres showed a significant correlation with these environmental parameters. SOP and PMD are stochastic in nature due to changes in the properties of the optical fibres and its positions because of both intrinsic and extrinsic perturbations. In our work, with only 184 PMD values measured and obtained by use of the FTB-5700 single-ended dispersion analyzer, the predicted theoretical Gaussian fit was obtained with a mean of 0.47 ps and standard deviation of 0.08 ps. This small standard deviation was justification for its robustness and accuracy. The statistical distributions for first-order polarization mode dispersion (FO-PMD) and second-order polarization mode dispersion (SO-PMD) for the first time were experimentally confirmed when measured using the FTB-5700 single-ended dispersion analyzer instrument for deployed aerial optical fibres. We were also able to determine the time scale over which to compensate FO-PMD in deployed aerial fibres using the directional time drift autocorrelation function method. It is slightly higher than 390 s for SOP measurements made on a particular windy and hot day. This is due to the fact that the changes of the PMD vector are known to be slower than the SOP changes. vi We also investigated the theoretical statistical distribution that corresponds to output SOP variations. The SOP variations can either be with wavelength (for buried fibre) or with time (for aerial fibre). Our results showed that the statistics of the relative SOP changes approached the distribution proposed by Foschini et al. (2000). Advanced optical modulation formats have become a key ingredient in the design of modern state-of-the-art wavelength-division-multiplexed (WDM) optical transmission systems. In our work, we investigated which of these advanced modulation formats is best suited for the South African network especially on systems that have links of aerial optical fibres. Keywords: aerial optical fibre, polarization mode dispersion (PMD), principal states of polarization (PSP), state of polarization (SOP), first-order PMD, second-order PMD.

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32

Xu, Yanping. "Fiber Random Grating and Its Applications." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36597.

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Femtosecond (fs) laser micromachining has been a useful technique either to modify and remove materials or to change the properties of a material, and can be applied to transparent and absorptive substances. Recently high-power fs laser radiation has drawn intensive attention for the induction of refractive index change to fabricate micro-structures in dielectric materials. This thesis studies the optical properties of a novel fiber random grating fabricated by fs laser micromachining technique and extends its applications from optical sensing to random fiber lasers and optical random bit generations. The thesis mainly consists of three parts. In the first part, the physical mechanism behind the fs laser micromachining technique and the fabrication of the fiber random grating are introduced. By employing a wavelength-division spectral cross-correlation algorithm, a novel multi-parameter fiber-optic sensor based on the fiber random grating is proposed and demonstrated to realize simultaneous measurements of temperature, axial strain, and surrounding refractive index. In the second part, Brillouin random fiber laser (BRFL) and Erbium-doped fiber random laser (EDFRL) are introduced, respectively. Firstly, we propose a novel Brillouin random fiber laser with a narrow linewidth of ~860 Hz based on the bi-directionally pumped stimulated Brillouin scattering (SBS) in a 10-km-long optical fiber. A random fiber Fabry-Perot (FP) resonator is built up through the pump depletion effects of SBS at both ends of the fiber. The novel laser is successfully applied for linewidth characterization beyond 860 Hz of light source under test. Secondly, the random grating-based FP resonator is introduced to build up a novel BRFL with narrow-linewidth of ~45.8Hz and reduced lasing threshold. The intensity and frequency noises of the proposed random laser are effectively suppressed due to the reduced resonating modes and mode competition. Finally, the fiber random grating is used as random distributed feedback in an EDFRL to achieve both static (temperature, strain) and dynamic (ultrasound) parameter sensing. Multiple lasing lines with high signal-to-noise ratio (SNR) up to 40dB are achieved, which gives an access for a high-fidelity multiple-static-parameter sensing application. By monitoring the wavelength shifts of each peak, temperature and strain have been simultaneously measured with small errors. The fiber random grating in the EDFRL is also able to sense the ultrasound waves. By achieving single mode lasing with the EDFRL, ultrasound waves with frequencies from 20kHz to 0.8MHz could be detected with higher sensitivity and SNR improvement up to 20dB compared with conventional piezoelectric acoustic sensors. In the third part, we demonstrate that a semiconductor laser perturbed by the distributed feedback from a fiber random grating can emit light chaotically without the time delay signature (TDS). A theoretical model is developed by modifying the Lang-Kobayashi model to numerically explore the chaotic dynamics of the laser diode subjected to the random distributed feedback. It is predicted that the random distributed feedback is superior to the single reflection feedback in suppressing the TDS. In experiments, The TDS with the maximum suppression is achieved with a value of 0.0088, which is the smallest to date.

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33

Bronk, Karen Srour. "Imaging based sensor arrays /." Thesis, Connect to Dissertations & Theses @ Tufts University, 1996.

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Thesis (Ph.D.)--Tufts University, 1996.
Adviser: David R. Walt. Submitted to the Dept. of Chemistry. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;

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34

Lee, Jong-Hyung. "Analysis and Characterization of Fiber Nonlinearities with Deterministic and Stochastic Signal Sources." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/26265.

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In this dissertation, various analytical models to characterize fiber nonlinearities have been applied, and the ranges of validity of the models are determined by comparing with numerical results. First, the perturbation approach is used to solve the nonlinear Schrödinger equation, and its range of validity is determined by comparing to the split-step Fourier method. In addition, it is shown mathematically that the perturbation approach is equivalent to the Volterra series approach. Secondly, root-mean-square (RMS) widths both in the time domain and in the frequency domain are modeled. It is shown that there exists an optimal input pulse width to minimize output pulse width based on the derived RMS models, and the functional form of the minimum output pulse width is derived. The response of a fiber to a sinusoidally modulated input which models an alternating bit sequence is studied to see its utility in measuring system performance in the presence of the fiber nonlinearities. In a single channel system, the sinusoidal response shows a strong correlation with eye-opening penalty in the normal dispersion region over a wide range of parameters, but over a more limited range in the anomalous dispersion region. The cross-phase modulation (CPM) penalty in a multi-channel system is also studied using the sinusoidally modulated input signal. The derived expression shows good agreement with numerical results in conventional fiber systems over a wide range of channel spacing, ∆f, and in dispersion-shifted fiber systems when ∆f > 100GHz. It is also shown that the effect of fiber nonlinearities may be characterized with stochastic input signals using noise-loading analysis. In a dense wavelength division multiplexed (DWDM) system where channels are spaced very closely, the broadened spectrum due to various nonlinear effects like SPM (self-phase modulation), CPM, and FWM (four-wave mixing) is in practice indistinguishable. In such a system, the noise-loading analysis could be useful in assessing the effects of broadened spectrum due to fiber nonlinearities on system performance. Finally, it is shown numerically how fiber nonlinearities can be utilized to improve system performance of a spectrum-sliced WDM system. The major limiting factors of utilizing fiber nonlinearities are also discussed.
Ph. D.

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35

Tomljenovic-Hanic, Snjezana. "Propagation effects in optical waveguides, fibres and devices /." View thesis entry in Australian Digital Theses Program, 2003. http://thesis.anu.edu.au/public/adt-ANU20040921.104741/index.html.

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Chadderdon, Spencer L. "Application Improvements of Slab-Coupled Optical Fiber Sensors." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/3976.

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This dissertation explores techniques for improving slab-coupled optical fiber sensor (SCOS) technology for use in specific applications and sensing configurations. SCOS are advantageous for their small size and all-dielectric composition which permit non-intrusive measurement of electric fields within compact environments; however, their small size also limits their sensitivity. This work performs a thorough analysis of the factors contributing to the performance of SCOS and demonstrates methods which improve SCOS, while maintaining its small dimensions and high level of directional sensitivity. These improvements include increasing the sensitivity by 9x, improving the frequency response to include sub 300 kHz frequencies, and developing a method to tune the resonances. The analysis shows that the best material for the slab waveguide is an electro-optic polymer because of its low RF permittivity combined with high electro-optic coefficient. Additional improvements are based on changing the crystal orientation to a transverse configuration, which enhances the sensitivity due to a combined increase in the effective electro-optic coefficient and electric field penetration into the slab. The transverse SCOS configuration not only improves the overall sensitivity but increases the directional sensitivity of the SCOS. Lithium niobate and electro-optic polymer are both experimentally shown to exhibit minimal frequency dependent sensitivity making them suitable for broad frequency applications. Simultaneous interrogation of multiple SCOS with a single tunable laser is achieved by tuning the resonant wavelengths of KTP SCOS so their resonances overlap.

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37

Wang, Yongxin. "High Speed Fiber Optic Spectrometer." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/30126.

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This dissertation presents the structure, operational principle and mathematical model of a novel high speed fiber optic spectrometer (HSFOS). In addition, the performance analysis is conducted and preliminary experimental results are listed and discussed. Such a spectrometer is highly desired by the ever-increasing applications of fiber optic sensors. In the recent decades, a variety of fiber optic sensors have been proposed, built and tested. Compared to their electronic counterparts, fiber optic sensors although still under development, are preferred more by certain industrial and medical applications which benefit from their unique properties such as immunity to electromagnetic interference, ability to withstand harsh environments and composition of purely dielectric materials. In recent years, new fiber optic sensors have been designed for applications where high response frequency up to a few hundred KHz is required while advantages of high accuracy and large dynamic range must be maintained. The bottle neck then emerged in the signal demodulation part of the sensor system. The quadrature phase detection could achieve high demodulation speed but with small dynamic range, medium accuracy and measurement ambiguity. The white light interferometry could provide a solution for high accuracy and large dynamic range measurement without ambiguity because of its absolute measurement nature. However the signal demodulation speed is limited due to the low spectrum acquisition rate of the existing spectrometers. The new HSFOS utilizes time domain dispersion of the sampled incoming light by dispersive fiber rather than the spatial dispersion employed by traditional spectrometers. In addition the signal that represents the spectrum of the light is naturally a serial signal which can be detected by a single detector and recorded by a high speed data acquisition device. Theoretical study of the operation principle is made and a mathematical model for the spectrometer is developed based on Marcuse's previous work. One major difference of the new derivation is that the propagation constant is expanded about the center circular frequency of each monochromatic light pulse instead of the center frequency of the chromatic light pulse which makes the physical picture of the chromatic light pulse evolution in a dispersive fiber clearer and facilitates both the analytical and numerical analysis. The profile of the dispersed chromatic light pulse could be treated as the superposition of all the dispersed monochromatic light pulses. Another major difference is the Taylor's series of the propagation constant is not truncated as it is in those previous work, which improves the accuracy of the model. Moreover, an approximate model is made which could further reduce the computation tasks in numerical simulations. Performance analysis for accuracy, resolution, speed and noise are conducted through numerical simulations based on the model and the experimental results. The sources of two different errors and their effects on accuracy are discussed respectively. The effects on spectral resolution by the properties of the modulation pulse and the fiber dispersion are studied. The results indicate that by using a rectangle modulation pulse under certain conditions, the resolution can be improved. The speed analysis gives that the spectrum acquisition rate can reach 1 million frames per second when the spectral width is less than 100 nm. In the noise analysis, the erbium-doped fiber amplifier (EDFA) is determined to be the dominant noise source. But by using two EDFAs, the overall signal to noise ratio is improved by 9.2 dB. The preliminary experimental results for FP sensor and FBG sensor signal demodulation are presented. The HSFOS for FP sensor signal demodulation achieves 15 nm resolution. By using the oversampling method, the HSFOS for FBG sensor signal demodulation achieves 0.05 nm spectral positioning resolution.
Ph. D.

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38

Blackmon, Richard Leious Jr. "Thulium Fiber Laser lithotripsy." Thesis, The University of North Carolina at Charlotte, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3563125.

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The Thulium Fiber Laser (TFL) has been studied as a potential alternative to the conventional Holmium:YAG laser (Ho:YAG) for the treatment of kidney stones. The TFL is more ideally suited for laser lithotripsy because of the higher absorption coefficient of the emitted wavelength in water, the superior Gaussian profile of the laser beam, and the ability to operate at arbitrary temporal pulse profiles. The higher absorption of the TFL by water helps translate into higher ablation of urinary stones using less energy. The Gaussian spatial beam profile allows the TFL to couple into fibers much smaller than those currently being used for Ho:YAG lithotripsy. Lastly, the ability of arbitrary pulse operation by the TFL allows energy to be delivered to the stone efficiently so as to avoid negative effects (such as burning or bouncing of the stone) while maximizing ablation. Along with these improvements, the unique properties of the TFL have led to more novel techniques that have currently not been used in the clinic, such as the ability to control the movement of stones based on the manner in which the laser energy is delivered. Lastly, the TFL has led to the development of novel fibers, such as the tapered fiber and removable tip fiber, to be used for lithotripsy which can lead to safer and less expensive treatment of urinary stones. Overall, the TFL has been demonstrated as a viable alternative to the conventional Ho:YAG laser and has the potential to advance methods and tools for treatment of kidney stones.

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39

Hart, Darlene Louise. "Nonlinear dynamics of multiwave mixing in an optical fiber." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/30047.

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40

Liang, Yu, and 梁羽. "Versatile photonic processor based on fiber optical parametric amplifiers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43085362.

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Liang, Yu. "Versatile photonic processor based on fiber optical parametric amplifiers." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43085362.

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42

Sloanes, Trefor J. "Measurement and application of optical nonlinearities in indium phosphide, cadmium mercury telluride and photonic crystal fibres." Thesis, University of St Andrews, 2009. http://hdl.handle.net/10023/723.

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The two-photon absorption (TPA) coefficient is measured in indium phosphide (InP) using femtosecond pulses to be 45cm/GW at 1.32μm. Nanosecond pulses are subsequently used to find the free-carrier refractive index cross-section, σ_r, and the free-carrier absorption coefficient, σ_fca. The quantity βσ_r is measured to be -113x10⁻²ºcm⁴/GW at 1.064μm and -84x10⁻²ºcm⁴/GW at 1.534μm. At 1.064μm, with β assumed to be 22cm/GW, the value suggested by theory, σ_r is -5.1x10⁻²ºcm³. Similarly, at 1.534μm, assuming β to be 20cm/GW gives a σ_r value of -4.1x10⁻²ºcm³. Due to refraction affecting the measurements of σ_fca, only an upper limit of 1x10⁻¹⁵cm² can be put on its value. The free-carrier experiments are repeated on two samples of cadmium mercury telluride (CMT) having bandgaps of 0.89eV and 0.82eV. For the first sample, β_σr is measured to be -148x10⁻²ºcm⁴/GW. Assuming β to be 89cm/GW gives a σ_r value of -1.7x10⁻²ºcm³ whilst σ_fca is found to be at most 3x10⁻¹⁵cm². Significant linear absorption occurs in the second sample which generates a large free-carrier population. It is shown that this significantly enhances the nonlinearities. Finally, the results of the work are tested by modelling a nonlinear transmission experiment, and the results found in this work give a closer fit to experimental results than the result of theory. Four-wave mixing (FWM) in a photonic crystal fibre is exploited to create a high output power optical parametric amplifier (OPA). To optimise the OPA conversion efficiency, the fibre length has to be increased to 150m, well beyond the walk-off distance between the pump and signal/idler. In this regime, the Raman process can take over from the FWM process and lead to supercontinuum generation. The OPA exhibits up to 40% conversion efficiency, with the idler (0.9μm) and the signal (1.3μm) having a combined output power of over 1.5W.

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Boiyo, Duncan Kiboi, and Romeo Gamatham. "Optimization of flexible spectrum in optical transport networks." Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/14609.

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The ever-increasing demand for broadband services by end-user devices utilising 3G/4G/LTE and the projected 5G in the last mile will require sustaining broadband supply from fibre-linked terminals. The eventual outcome of the high demand for broadband is strained optical and electronic devices. The backbone optical fibre transport systems and techniques such as dense wavelength division multiplexing (DWDM), higher modulation formats, coherent detection and signal amplification have increased both fibre capacity and spectrum efficiency. A major challenge to fibre capacity and spectrum efficiency is fibre-faults and optical impairments, network management, routing and wavelength assignment (RWA). In this study, DWDM and flexible spectrum techniques such as wavelength assignment and adjustment, wavelength conversion and switching, optical add and drop multiplexing (OADM) and bitrate variable transmission have been experimentally optimized in a laboratory testbed for short- and long-haul optical fibre networks. This work starts by experimentally optimising different transmitters, fibre-types and receivers suitable for implementing cost effective and energy efficient flexible spectrum networks. Vertical cavity surface-emitting lasers (VCSELs) and distributed feedback (DFB) lasers have been studied to provide up to 10 Gb/s per channel in 1310 nm and 1550 nm transmission windows. VCSELs provide wavelength assignment and adjustment. This work utilises the non-return-to-zero (NRZ) on-off keying (OOK) modulation technique and direct detection due to their cost and simplicity. By using positive intrinsic negative (PIN) photo-receivers with error-free BER sensitivity of -18±1 dBm at the acceptable 10-9-bit error rate (BER) threshold level, unamplified transmission distances between 6 km and 76 km have been demonstrated using G.652 and G.655 single mode fibres (SMFs). For the first time, an all optical VCSEL to VCSEL wavelength conversion, switching, transmission at the 1550 nm window and BER evaluation of a NRZ data signal is experimentally demonstrated. With VCSEL wavelength conversion and switching, wavelength adjustments to a spectrum width of 4.8 nm (600 GHz) can be achieved to provide alternative routes to signals when fibre-cuts and wavelength collision occurs therefore enhancing signal continuity. This work also demonstrates a technique of removing and adding a wavelength in a bundle of DWDM and flexible channels using an OADM. This has been implemented using a VCSEL and a fibre Bragg grating (FBG) providing a wavelength isolation ratio of 31.4 dB and ~0.3 𝑑𝐵 add/drop penalty of 8.5 Gb/s signal. As a result, an OADM improves spectrum efficiency by offering wavelength re-use. Optical impairments such as crosstalk, chromatic dispersion (CD) and effects of polarization mode dispersion (PMD) have been experimentally investigated and mitigated. This work showed that crosstalk penalty increased with fibre-length, bitrate, interfering signal power and reduced channel spacing and as a result, a crosstalk-penalty trade-off is required. Effects of CD on a transmitted 10 Gb/s signal were also investigated and its mitigation techniques used to increase the fibre-reach. This work uses the negative dispersion fibres to mitigate the accumulated dispersion over the distance of transmission. A 5 dB sensitivity improvement is reported for an unamplified 76 km using DFB transmitters and combination of NZDSF true-wave reduced slope (TW-RS) and submarine reduced slope (TW-SRS) with + and – dispersion coefficients respectively. We have also demonstrated up to 52 km 10 Gb/s per channel VCSEL-based transmission and reduced net dispersion. Experimental demonstration of forward Raman amplification has achieved a 4.7 dB on-off gain distributed over a 4.8 nm spectral width and a 1.7 dB improvement of receiver sensitivity in Raman-aided 10 Gb/s per wavelength VCSEL transmission. Finally, 4.25-10 Gb/s PON-based point to point (P2P) and point to multipoint (P2MP) broadcast transmission have been experimentally demonstrated. A 10 Gb/s with a 1:8 passive splitter incurred a 3.7 dB penalty for a 24.7 km fibre-link. In summary, this work has demonstrated cost effective and energy efficient potential flexible spectrum techniques for high speed signal transmission. With the optimized network parameters, flexible spectrum is therefore relevant in short-reach, metro-access and long-haul applications for national broadband networks and the Square Kilometre Array (SKA) fibre-based signal and data transmission.

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44

Battiato, James Michael 1966. "Diffractive microlenses for fiber optic array interconnects." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278187.

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The design, fabrication, and testing of diffractive microlens arrays for use in fiber optic interconnects is presented. Advantages of using diffractive microlenses for fiber interconnects instead of refractive microlenses are discussed. A theoretical discussion of diffractive lens operation including the effects of chromatic aberration on fiber coupling is given, along with equations for mask generation. From these equations, a set of masks to fabricate an array of four phase level diffractive microlenses was produced. Experimental procedures for the fabrication of diffractive microlenses from this mask set are presented. Arrays of binary lenses in photoresist with depth errors of less than 4% were fabricated and test results are given. A novel fiber optic tap utilizing both surface relief microlenses and a volume holographic element is demonstrated. In addition, a fiber array coupler using silicon V-grooves and an array of diffractive lenses is also demonstrated.

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45

Silva, Muñoz Rodrigo. "Structural Health Monitoring Using Embedded Fiber Optic Strain Sensors." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/SilvaMunozR2008.pdf.

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46

Bechter, Andrew, Jonathan Crass, Ryan Ketterer, Justin R. Crepp, Robert O. Reynolds, Eric Bechter, Philip Hinz, et al. "On-sky single-mode fiber coupling measurements at the Large Binocular Telescope." SPIE-INT SOC OPTICAL ENGINEERING, 2016. http://hdl.handle.net/10150/622009.

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The demonstration of efficient single-mode fiber (SMF) coupling is a key requirement for the development of a compact, ultra-precise radial velocity (RV) spectrograph. iLocater is a next generation instrument for the Large Binocular Telescope (LBT) that uses adaptive optics (AO) to inject starlight into a SMF. In preparation for commissioning iLocater, a prototype SMF injection system was installed and tested at the LBT in the Y-band (0.970-1.065 mu m). This system was designed to verify the capability of the LBT AO system as well as characterize on-sky SMF coupling efficiencies. SMF coupling was measured on stars with variable airmasses, apparent magnitudes, and seeing conditions for six half-nights using the Large Binocular Telescope Interferometer. We present the overall optical and mechanical performance of the SMF injection system, including details of the installation and alignment procedure. A particular emphasis is placed on analyzing the instrument's performance as a function of telescope elevation to inform the final design of the fiber injection system for iLocater.

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47

Grimsley, Jonathan Scot. "Light Loss In Single Mode Fiber Optical Switches." Master's thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/37142.

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Light loss in single mode fiber optical switches is investigated. Loss due to reflection, aberration and fiber misalignment are evaluated. A simple model of image to fiber end face overlap for the fiber/lens system is developed. The intensity distribution of light in the fiber and imaging system is assumed to be gaussian. It was found that aberration is a major cause of loss and that fiber misalignment did not cause as much loss as expected. Loss due to reflection is assumed to be minimal due to the presence of anti-reflection coatings on the optical components.
Master of Science

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48

Abobaker, Abdosllam M. "Analytical design of dispersion-managed optical fibre transmission systems." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2008. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=24668.

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Dods, Sarah D. "Homodyne crosstalk in wavelength-division multiplexed ring and cus networks /." Connect to thesis, 2000. http://eprints.unimelb.edu.au/archive/00000597.

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Ulmer, Todd G. "Resonant-cavity-enhanced surface-emitted second-harmonic generation for optical time-division demultiplexing." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/13323.

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Dissertations / Theses on the topic 'Fiber optics'

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