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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Mutual coupling in a three-element, parallel-plate waveguide array by wedge diffraction and surface integration techniques /

Mikuteit, Siegfried January 1967 (has links)
No description available.
62

Waveguide applications of impedance surfaces /

Dybdal, Robert B. January 1968 (has links)
No description available.
63

Analysis and modeling of lossy planar optical waveguides and application to silicon-based structures

Remley, Catherine A. 20 June 1995 (has links)
This work is concerned with the modeling and analysis of lossy planar dielectric optical waveguides. Loss mechanisms which affect propagation characteristics are reviewed, and various representations of the propagation constant in the lossy case are defined. Waveguide structures which are susceptable to absorption and/or to leakage loss, in particular silicon-based structures, are discussed. The modeling and analysis of these waveguides by various computational techniques is considered. Two computational methods, the commonly used transfer matrix method and the recently developed impedance boundary method of moments (IBMOM), are reviewed and extended to the complex domain. A third computational method, which offers improved convergence of the IBMOM for structures with large stepwise changes in refractive index, is formulated. In this approach, the regions containing refractive index discontinuities are replaced by equivalent extended impedance boundary conditions, and expansion of the transverse field in the remaining region of continuous refractive index profile is carried out. A significant increase in the rate of convergence is demonstrated for various waveguide structures, including an anti-resonant reflecting optical waveguide (ARROW) structure. Two applications of the IBMOM with extended impedance boundary conditions are presented. In the first, the method is applied to the design of a chemical sensor. The sensor, a silicon-based ARROW structure, is designed to measure the refractive index of certain chemical substances with a high degree of accuracy. In a second application, graded index SiON waveguides fabricated at Oregon State University are characterized and compared to the theoretical model. Excellent agreement between the theoretical and measured coupling angles is shown. / Graduation date: 1996
64

Classical and quantum dynamics of atomic systems in the proximity of dielectric waveguides

Modoran, Andrei V., January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 197-200).
65

A theoretical study of the propagation characteristics of some optical waveguides by the beam propagation method /

Osborne, Robert. January 1986 (has links)
No description available.
66

Design and fabrication of silicon on insulator optical waveguide devices /

Harvey, Eric J. January 2006 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2006. / Typescript. Includes bibliographical references (leaves 171-181).
67

A theoretical study of the propagation characteristics of some optical waveguides by the beam propagation method /

Osborne, Robert. January 1986 (has links)
No description available.
68

Theoretical evaluation, analysis and design of surface-mounted waveguide (SMW) components for on-substrate integrated microwave applications

Schorer, Jan 07 April 2016 (has links)
This dissertation presents the research on a novel combination of well proven concepts for passive electromagnetic wave-guiding components. The goal of this work is to overcome and minimize losses occurring in frequency-selective structures. The work aims to contribute to an improvement in the application of conventional and Substrate Integrated Waveguide (SIW). It is proposed to mount conventional waveguide structures on the surface of printed circuit boards containing substrate integrated waveguides. The crossover technology is referred to as Surface Mounted Waveguide (SMW). Theoretical investigations are performed, proving the validity and superiority of the proposed structure focusing on the elimination of losses, while maintaining low space consumption and printed circuit board technology compatible manufacturing processes. Additionally, a mode matching technique is developed and successfully applied to prototype such components. The validation of this method reveals superior computational speed when compared to commercial available electromagnetic field solvers. The proposed structures are validated by measurements of several prototypes, including coupled SMW resonator filters, combined SMW and SIW resonator filters, a SMW triple-layer diplexer and single individual SMW resonator filters. The experimental verification shows good agreement between theory and measurements. Moreover, the comparison to other technologies proves the superiority of the proposed structures. / Graduate
69

Optical branching and coupling devices.

January 1988 (has links)
by Hung Wing-yiu. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1988. / Bibliography: leaves 98-103.
70

Optical waveguides and devices in lithium niobate by the Proton exchange process.

January 1992 (has links)
by Loi Kwok Kwong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 197-222). / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- An Overview of Integrated Optics --- p.1 / Chapter 1.2 --- Application of Lithium Niobate Integrated Optical Circuit --- p.4 / Chapter 1.3 --- Summary --- p.5 / Chapter Chapter 2 --- Optical Waveguide Theory --- p.7 / Chapter 2.1 --- Introduction --- p.7 / Chapter 2.2 --- Ray Optics Treatment of Planar Waveguide --- p.7 / Chapter 2.2.1 --- Step-index Waveguide --- p.8 / Chapter 2.2.2 --- Graded-index Waveguide --- p.13 / Chapter 2.3 --- Optical Channel Waveguide --- p.20 / Chapter 2.3.1 --- Marcatili's Method --- p.22 / Chapter 2.3.2 --- Effective Index Method --- p.26 / Chapter 2.4 --- Summary --- p.30 / Chapter Chapter 3 --- Waveguide Fabrication Technology --- p.32 / Chapter 3.1 --- Properties of Substrate Materials --- p.32 / Chapter 3.1.1 --- Glass --- p.32 / Chapter 3.1.2 --- Semiconductor --- p.34 / Chapter 3.1.3 --- Ferroelectric Material --- p.35 / Chapter 3.2 --- Waveguide Fabrication Techniques --- p.40 / Chapter 3.2.1 --- Ion Implantation --- p.40 / Chapter 3.2.2 --- Titanium Indiffusion --- p.41 / Chapter 3.2.3 --- Proton Exchange --- p.44 / Chapter 3.3 --- Summary --- p.48 / Chapter Chapter 4 --- Fabrication and Measurement of Optical Waveguides --- p.49 / Chapter 4.1 --- Fabrication of Optical Waveguides --- p.49 / Chapter 4.1.1 --- Planar Waveguides --- p.49 / Chapter 4.1.1.1 --- Substrate Cutting --- p.49 / Chapter 4.1.1.2 --- Substrate Cleaning --- p.49 / Chapter 4.1.1.3 --- Proton Exchange --- p.50 / Chapter 4.1.1.4 --- Post-exchange Annealing --- p.51 / Chapter 4.1.2 --- Channel Waveguides --- p.51 / Chapter 4.1.2.1 --- Patterning Technique: Photolithography and Lift-off --- p.51 / Chapter 4.1.2.2 --- Proton Exchange and Annealing --- p.56 / Chapter 4.1.2.3 --- Lapping and Polishing --- p.56 / Chapter 4.2 --- Measurement of Waveguide Parameters --- p.57 / Chapter 4.2.1 --- Coupling of Light into Optical Waveguide --- p.57 / Chapter 4.2.1.1 --- Prism Coupling --- p.58 / Chapter 4.2.1.2 --- End-fire Coupling --- p.60 / Chapter 4.2.2 --- Effective Index --- p.63 / Chapter 4.2.3 --- Refractive Index Profile --- p.63 / Chapter 4.2.4 --- Waveguide Depth --- p.67 / Chapter 4.2.5 --- Propagation Loss --- p.67 / Chapter 4.2.6 --- Near-field Intensity Profile --- p.69 / Chapter 4.3 --- Summary --- p.74 / Chapter Chapter 5 --- Results and Discussions --- p.75 / Chapter 5.1 --- Proton-exchanged Waveguides Using Phosphoric Acid --- p.75 / Chapter 5.2 --- Proton-exchanged LiNb03 Waveguides Using Toluic Acid --- p.112 / Chapter 5.3 --- Proton-exchanged LiNb03 Waveguides Using Stearic Acid --- p.127 / Chapter 5.4 --- Proton-exchanged LiNb03 Waveguides Using Cinnamic Acid --- p.148 / Chapter 5.5 --- Structural Characteristics of Proton-exchanged Waveguides --- p.174 / Chapter 5.5.1 --- Thermogravimetric Analysis --- p.174 / Chapter 5.5.2 --- Raman Spectroscopy --- p.174 / Chapter 5.5.3 --- Infrared Spectrometry --- p.179 / Chapter 5.5.4 --- Double Crystal X-ray Diffractometry --- p.185 / Chapter 5.6 --- Summary --- p.190 / Chapter Chapter 6 --- Conclusions --- p.192 / References --- p.197 / Chapter Appendix 1 --- Error Estimations --- p.219 / Chapter Appendix 2 --- List of Publications --- p.221

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