Time-domain Polarity Coincidence Correlators (PCC) have been studied for the possible extension of these theories to the spatial-domain in the context of an optical PCC. The existing body of knowledge has been found to be inadequate for direct application to the spatial-domain. However, by remodeling the type of clipper or hardlimiter used in the development of the existing theory from a signum (bipolar) clipper to a binary (unipolar) clipper, a new expression for the output signal-to-noise ratio of an optical PCC is developed. This modification is necessary to account for the unipolar nature of light intensity. Both the existing time-domain and new spatial-domain PCC expressions are valid for the case of additive narrowband (bandwidth much less than the signal frequency) Gaussian-distributed noise at the inputs of the correlator. An optical experiment was constructed to evaluate a new type of binary spatial light modulator, the Litton Data Systems 128 x 128 Magneto-Optic Array. To accomplish this, a noiseless single frequency (fc) sinusoidal one-dimensional reference was correlated with a sinusoidal signal of equal frequency and phase to which gaussian-distributed noise was added. Both signals were hardlimited prior to correlation. Noise sources having bandwidths of 0.1 fc and0.5 fc were investigated to test the robustness of the narrowband constraints. The input data sets had signal-to-noise ratios of -10.0dB and -20.0dB. For both of these conditions the experimental data was found to be in excellent agreement with the new expression for the narrowband case. In the wideband case, the results were significantly different from the new expression, thereby corroborating the necessity of meeting the narrowband constraint. Both the time-domain and spatial-domain expressions are highly-dependent on the output filtering (after hardlimiting and multiplication) characteristics. The effect of filter insertion loss, at the signal frequency (fc), for the unipolar or optical case was examined as part of this research. It was found that the output signal-to-noise ratio increases as the carrier frequency components are attenuated. This affect, which is a direct result of the multiplication of the reference with the input signal within the PCC, is greater for input signal-to-noise ratios above -10dB. For input signal-to-noise ratios below -10dB the output signal-to-noise ratio asymptotically approaches a constant. This output signal-to-noise independence on input signal-to-noise is due to the combined effect limiting signal (which is mostly noise) amplitude information by the hardlimiter and the bounding of the spatial correlation by the low pass filter.

by Lee, Kai Kwong Dennis = 一激光束對在光折變晶體中之另一激光束的影響 / 李啓光. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 106-109). / Text in English; abstracts in English and Chinese. / by Lee, Kai Kwong Dennis = Yi ji guang shu dui zai guang zhe bian jing ti zhong zhi ling yi ji guang shu de ying xiang / Li Qiguang. / Acknowledgments --- p.i / Abstract --- p.ii / Table of Content --- p.iv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Theory --- p.4 / Chapter 2.1 --- Two-wave Coupling --- p.4 / Chapter 2.2 --- Four-wave Mixing --- p.10 / Chapter 2.3 --- Fanning --- p.13 / Chapter 2.4 --- Phase-conjugation --- p.16 / Chapter 2.5 --- Spatial Solitons --- p.19 / Chapter Chapter 3 --- "Experiments,Results and Discussion" --- p.26 / Chapter 3.1 --- Measurements of Optically Induced Refractive Index Change --- p.26 / Chapter 3.2 --- Optical Control Experiments --- p.65 / Chapter 3.3 --- Soliton Experiments --- p.80 / Chapter Chapter 4 --- Concluding Remarks and Suggested Further Studies --- p.99 / References --- p.105

by Han Dejun. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves [117]-[129]). / Abstract --- p.ii / Acknowledgment --- p.iv / Table of Contents --- p.v / Chapter 1. --- Introduction --- p.1-1 / Chapter 1.1 --- The Current Situation of Space-division Optical Switches --- p.1-1 / Chapter 1.1.1 --- Digital Optical switches (DOS) --- p.1-2 / Chapter 1.1.2 --- Twin-guide amplifier (TGA) --- p.1-3 / Chapter 1.1.3 --- Direction coupler with amplifiers --- p.1-4 / Chapter 1.1.4 --- Total internal reflection type switch with amplifier --- p.1-5 / Chapter 1.1.5 --- Semiconductor optical amplifier gate switches --- p.1-6 / Chapter 1.2 --- Existing Problems --- p.1-9 / Chapter 1.3 --- New Proposals --- p.1-10 / Chapter 1.3.1 --- New features --- p.1-11 / Chapter 1.3.2 --- New technology for OEIC --- p.1-13 / Chapter 1.3.3 --- Expected improvement in performance --- p.1-14 / Chapter 1.4 --- Organization of thesis --- p.1-17 / Chapter 2. --- Band Lineup And Optical Gain Calculation --- p.2-1 / Chapter 2.1 --- Introduction --- p.2-1 / Chapter 2.2 --- Band Lineup for InGaAsP MQW Structures --- p.2-3 / Chapter 2.2.1 --- Derivation According to Ishikawa et al.'s Scheme --- p.2-3 / Chapter 2.2.2 --- Derivation According to Krijn's scheme --- p.2-5 / Chapter 2.2.3 --- Improved band lineup calculation scheme --- p.2-7 / Chapter 2.3 --- Gain and Spontaneous Emission Rate Expressions --- p.2-13 / Chapter 2.3.1 --- Optical gain expressions --- p.2-13 / Chapter 2.3.2 --- Spontaneous Emission Rate Expressions --- p.2-16 / Chapter 2.3.3 --- Polarization characteristics --- p.2-17 / Chapter 2.4 --- Optical Absorption and Its Polarization Sensitivity --- p.2-18 / Chapter 2.4.1 --- Absorption in an intermixed QW Structure --- p.2-18 / Chapter 2.4.2 --- Electro-optical Absorption --- p.2-19 / Chapter 3. --- Design of the Optical Switches --- p.3-1 / Chapter 3.1 --- Design of Material Layer Structure --- p.3-2 / Chapter 3.2 --- Design of Device Geometrical Structure --- p.3-7 / Chapter 3.3 --- Optical Gain in Polarization Insensitive Gain Medium-- An Example --- p.3-8 / Chapter 3.4 --- Optical Absorption in Polarization Insensitive Gain Medium-- An Example --- p.3-15 / Chapter 4. --- Fabrication Technology --- p.4-1 / Chapter 4.1 --- Passive Waveguide Formation --- p.4-2 / Chapter 4.1.1 --- Impurity-free vacancies diffusion technology --- p.4-3 / Chapter 4.1.2 --- High energy ion implantation enhanced intermixing technology --- p.4-4 / Chapter 4.1.3 --- Elevated temperature O+ HE-IIEI of MQWs --- p.4-6 / Chapter 4.2 --- Oxygen Implant Isolation --- p.4-6 / Chapter 4.3 --- Self Aligned Ridged Waveguide Technology --- p.4-7 / Chapter 4.4 --- Reduction of Effective Facet Reflectivity --- p.4-11 / Chapter 4.5 --- Fabrication Process Flow --- p.4-12 / Chapter 4.5.1 --- Layer structure of the material --- p.4-12 / Chapter 4.5.2 --- Fabrication process flow for the Y-junction optical switches --- p.4-14 / Chapter 4.6 --- Schematic Structure of the Fabricated Switches --- p.4-19 / Chapter 5. --- Experimental Results --- p.5-1 / Chapter 5.1 --- High Energy Ion Implantation Enhanced Intermixing of Quantum Wells --- p.5-2 / Chapter 5.1.1 --- High energy ion implantation --- p.5-2 / Chapter 5.1.2 --- Rapid thermal annealing --- p.5-4 / Chapter 5.2 --- Photoluminescence --- p.5-6 / Chapter 5.3 --- Electroluminescence --- p.5-9 / Chapter 5.4 --- Current-Voltage characteristics --- p.5-12 / Chapter 5.5 --- Guided-Wave Optoelectronic Measurement --- p.5-14 / Chapter 5.5.1 --- Setup of the measurement --- p.5-14 / Chapter 5.5.2 --- Measurement of absorption loss for the blue-shifted QW structure --- p.5-16 / Chapter 5.5.3 --- Optical losses measurement by Fabry-Perot interference method --- p.5-18 / Chapter 5.5.4 --- Electroabsorption peak shift in IIEI wafer --- p.5-21 / Chapter 5.6 --- Oxygen Implant Isolation --- p.5-21 / Chapter 5.7 --- Characteristics of Optical Switches --- p.5-23 / Chapter 5.7.1 --- Current-voltage characteristics --- p.5-23 / Chapter 5.7.2 --- Optical mode and transmission characteristics --- p.5-24 / Chapter 5.7.3 --- Switch characteristics --- p.5-29 / Chapter 5.7.4 --- Discussion --- p.5-32 / Chapter 6. --- Conclusion and Future Studies --- p.6-1 / Chapter 6.1 --- Conclusion --- p.6-1 / Chapter 6.1.1 --- The major contributions to the Y-JOS --- p.6-1 / Chapter 6.1.2 --- The major contribution to the bandgap engineering for InGaAs(p)/InP heterostructure --- p.6-3 / Chapter 6.1.3 --- The major contributions to the HE-IIEI technology --- p.6-4 / Chapter 6.2 --- Topics for Future Studies --- p.6-5 / Chapter 6.2.1 --- Band lineup and optical gain calculation --- p.6-5 / Chapter 6.2.2 --- Optimization of HE-IIEI technology --- p.6-6 / Chapter 6.2.3 --- Optimization of the Fabrication of Y-JOS --- p.6-7 / Reference --- p.R1 / Appendix A Characteristics Of Strained Quantum Wells --- p.A1 / Appendix B Effective Index Change Induced by Quantum Well Intermixing --- p.A3 / Appendix C Abbreviation --- p.A13 / Appendix D List of Publications --- p.A14

Guo Bin = 光折變摻銅鉀鈉鈮酸鍶鋇和摻鐵鈮酸鋰晶體中的二波耦合及摻鐵鈮酸鋰晶體中的亮光伏空間孤子 / 郭斌. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / Guo Bin = Guang zhe bian shan tong jia na ni suan si bei he shan tie ni suan li jing ti zhong de er bo ou he ji shan tie ni suan li jing ti zhong de liang guang fu kong jian gu zi / Guo Bin. / Acknowledgements --- p.i / Abstract --- p.ii / Table of Contents --- p.v / Chapter Chapter 1 --- Introduction --- p.1 / References --- p.6 / Chapter Chapter 2 --- Background --- p.7 / Chapter 2.1 --- Photorefractive Effect Based on Band Transport Model --- p.7 / Chapter 2.2 --- Photovoltaic Effect --- p.15 / Chapter 2.3 --- Surface Charge Recombination in Fe:LiNb〇3 Crystals --- p.17 / References --- p.19 / Chapter Chapter 3 --- Noise of Two-Wave Mixing in Cu:KNSBN Crystal --- p.20 / Chapter 3.1 --- Introduction --- p.20 / Chapter 3.2 --- Experimental Setup --- p.22 / Chapter 3.3 --- Results and Discussion --- p.23 / Chapter 3.4 --- Conclusion --- p.29 / References --- p.30 / Chapter Chapter 4 --- Bright Photovoltaic Spatial Soliton in Fe:LiNb03 Crystals / Chapter 4.1 --- Introduction --- p.32 / Chapter 4.2 --- Theory --- p.33 / Chapter 4.3 --- Experimental Setup --- p.36 / Chapter 4.4 --- Results and Discussion --- p.39 / Chapter 4.5 --- Conclusion --- p.58 / References --- p.59 / Chapter Chapter 5 --- Two-Wave Mixing of Narrow Laser Beams in a Fe:LiNbO3 Crystal --- p.60 / Chapter 5.1 --- Introduction --- p.60 / Chapter 5.2 --- Theory of Two-Wave Mixing --- p.62 / Chapter 5.3 --- A Simplified Analysis of Two-Wave Mixing of Narrow Beams --- p.66 / Chapter 5.4 --- Experimental Setup --- p.70 / Chapter 5.5 --- Results and Discussion --- p.71 / Chapter 5.6 --- Conclusion --- p.86 / References --- p.87 / Chapter Chapter 6 --- Two-Wave Mixing of Narrow Laser Beams with an Incoherent Background Beam --- p.89 / Chapter 6.1 --- Theory --- p.89 / Chapter 6.2 --- Experimental Setup --- p.93 / Chapter 6.3 --- Results and Discussion --- p.94 / Chapter 6.4 --- Conclusion --- p.105 / References --- p.106 / Chapter Chapter 7 --- Conclusion and Future Outlook --- p.107

Coplanar microstrip structures placed on dielectric substrates are used as high frequency electro-optic modulators. The method of lines, a mathematical technique for solving partial differential equations, has been applied to solve for the propagation characteristics of such a configuration. It has been determined that simple transmission line models are adequate to describe this system. The propagation characteristics are expressed in terms of the equivalent impedance and the phase velocity of the signal on the microstrip. In order to maximize the effective bandwidth of the modulator, the impedance is matched to that of the surrounding dielectric substrate, and the difference in the phase velocities of the two signals is minimized. The numerical technique developed here allows for the analysis of inhomogeneous dielectric substrates, so that trench structures for tuning the propagation characteristics to their desired values can be modelled. The numerical results for typical structures are presented, and suggest that the method of lines is a viable one for analyzing these modulator structures. / Graduation date: 1991

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 220-229). Available also in a digital version from Dissertation Abstracts.

Polymer based photovoltaic cells are being intensively investigated. In such cells three key processes need to occur; namely light absorption, charge separation of the exciton, and transport of the separated charges to the electrodes. Light absorption is reliant on the optical density of the polymer. In general charge separation is achieved by blending an electron acceptor with the polymer film. However, blending materials gives rise to potentially unreliable manufacturing and lifetime issues. This thesis describes the preparation of poly(l,4-phenylenevinylene) derivatives containing dipoles in which the process of charge separation can be achieved intramolecularly. The dipole was created with the use of electron donating alkoxy groups attached to the polymer backbone, and electron withdrawing nitro group attached to the fluorenyl side chains. These groups are believed to facilitate the dissociation of the photogenerated exciton, and potentially stabilise the holes and electrons that are formed when the exciton is separated. The fluorenyl side chains were attached to the polymer backbone via biphenyl or vinyl linkages. The polymers were primarily formed using the Gilch method and the conjugated polymers were obtained either via a soluble precursor route or directly from the monomer. The photophysical properties were studied for polymers with the fluorenyl side-chains as they were found to be more easily formed and stable. For poly[2-(7-nitro-9,9-dipropylfluorenyl)-5-(2'- ethylhexyloxy)-l,4-phenylenevinylene] it was found that the photoluminescence quantum yield dropped by a factor of eight relative to the polymer without the nitro group. It was further elucidated that this was due to the exciton being separated. Solar cells containing the polymers from this study showed modest performance.

This thesis is concerned with the experimental determination of surface displacements of material foils by means of an automatic evaluation of the holographic interferograms obtained in testing. The experimental work utilizes a newly developed method referred to as the "holographic-electro-optical" technique that employs a specially designed microcomputer unit. The experimental procedure and the microcomputer organization are fully described. The application of this technique is illustrated by the evaluation of strain field and thickness changes at a large number of points on both sides of a commercial newsprint paper sample subjected to uniaxial loads. Furthermore, a new quantity called the "volumetric mass density" is introduced for this material for the first time that is experimentally evaluated and correlated to the obtained strain field. In the conclusion of this thesis general remarks concerning the holographic-electro-optical technique are given and the obtained results for the newsprint sample and future research are indicated.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 111-116).