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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.
11

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.
12

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
13

Optical analogue of interacting quantum and mechanical systems: spin and plane pendulum. / 以光學模擬量子自旋和機械鐘擺的相互作用 / CUHK electronic theses & dissertations collection / Optical analogue of interacting quantum and mechanical systems: spin and plane pendulum. / Yi guang xue mo ni liang zi zi xuan he ji xie zhong bai de xiang hu zuo yong

January 2013 (has links)
Au-Yeung, Kin Chung = 以光學模擬量子自旋和機械鐘擺的相互作用 / 歐陽健聰. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 80-81). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Au-Yeung, Kin Chung = Yi guang xue mo ni liang zi zi xuan he ji xie zhong bai de xiang hu zuo yong / Ouyang Jiancong.
14

Experimental and theoretical studies of distributed feedback waveguide lasers. / 分佈反饋波導激光器的實驗與理論研究 / CUHK electronic theses & dissertations collection / Experimental and theoretical studies of distributed feedback waveguide lasers. / Fen bu fan kui bo dao ji guang qi de shi yan yu li lun yan jiu

January 2006 (has links)
As an effective compact coherent light source, distributed feedback (DFB) waveguide laser has attracted much attention recently. Sol-gel Mass synthesized at low temperatures is a very useful optical material. DFB waveguide lasers based on sol-gel glasses were experimentally and theoretically investigated in this thesis. In addition, microring lasers based on a conjugated polymer, which is emerging as an important class of laser material, were also studied in this thesis. / DFB lasing characteristics of various dyes in zirconia waveguides and in solutions were investigated. Intensity modulation and polarization modulation were used to generate the laser action. The laser output showed different polarization characteristics and threshold energy variation when the feedback mechanism was changed from intensity modulation to polarization modulation. In addition, near infrared (NIR) wide-band tuning DFB lasing operation was achieved in NIR dve-doped sol-gel waveguides by using intensity modulation. / Microring cavities were fabricated by depositing poly(2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylene vinylene) (MEH-PPV) on glass fibers by a dip coating method. Laser emissions in whispering gallery modes using microring cavities were observed by pumping with a frequency-doubled Nd:YAG laser. The threshold energy of the MEH-PPV microring laser was as low as 10 nJ per pulse. The polarization characteristics of the microring lasers were studied and a polarization model was developed to explain the observed phenomena. / Theoretical expressions for the angle-dependent coupling coefficients of DFB lasers were derived to explain the polarization properties of the DFB lasers. The coupling and gain coefficients of the two orthogonal polarization components of DFB lasers are strongly dependent on the intersection angle and the polarization states of the two crossing pump heams. The experimental results of DFB lasing in dye solutions have verified our theoretical predictions. / Titania zirconia organically modified silicate (TiO2-ZrO 2-ORMOSIL) DFB waveguide lasers were demonstrated. The output polarization and output wavelength of TiO2-ZrO2-ORMOSIL DFB waveguide lasers were found to be dependent on the polarization of the crossing pump beams from a frequency-doubled Nd:YAG laser. Up to sixteen Output wavelengths corresponding to eight pairs of polarized output from eight propagation modes were observed simultaneously for a planar waveguide with a thickness of 6.7 mum. / Two-photon-pumped DFB lasing action with a narrow linewidth output was demonstrated in zirconia waveguides doped with trans-4-[p-( N-hydroxyethyl-N-methylamino)styryl]-N-methylpyridinium p-toluene sulfonate a compound that shows strong two-photon upconverted emission around 620 nm. Transient gratings for coherent scattering were generated in the waveguides by crossing two 1.06 mum beams. DFB laser emission with the linewidth as narrow as 60 pm was observed. Operating at the third-order Bragg condition, tunable TE mode laser emission was achieved from 618 to 640 nm. TM output modes from the DFB laser were observed when the crossing beams were changed from s-polarized to p-polarized. / Wang Jun = 分佈反饋波導激光器的實驗與理論研究 / 王俊. / "September 2006." / Adviser: King Young Wong. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1702. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 165-183). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307. / Wang Jun = Fen bu fan kui bo dao ji guang qi de shi yan yu li lun yan jiu / Wang Jun.
15

Electro-optic polymer-based monolithic waveguide devices with multi-functions of amplification switching and modulation

An, Dechang. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.
16

Optical waveguides for control of antenna arrays

Howley, Brie 28 August 2008 (has links)
Not available / text
17

Electro-optic polymer-based monolithic waveguide devices with multi-functions of amplification switching and modulation

An, Dechang 14 March 2011 (has links)
Not available / text
18

Interferometric optical phase measurement techniques

Koliopoulos, Chris L. January 1981 (has links)
No description available.
19

Computer programs for the optical analysis and design of thin film planar waveguides

Reinbolt, Bruce James, 1950- January 1975 (has links)
No description available.
20

Theoretical and experimental studies on active and passive 3-branch waveguides and their derivatives

Bélanger, Michel, 1956- January 1986 (has links)
In this thesis, passive and active 3-branch Ti:LiNbO$ sb3$ waveguide devices were investigated. A multimode field-matching technique was employed to predict the power division in a passive 3-branch waveguide power divider. The limitation and range of validity of this method were pointed out. An alternative method was also employed to predict the power division when coupling between two neighbouring branches is not negligible, as is the case when the branching angle becomes small. The multimode field-matching method was also employed to predict the power division in an active 3-branch waveguide switch, where switching is achieved through the electrooptic effect of LiNbO$ sb3$. The edge effect of the electrodes on the beam steering was also considered. A linear mode-confinement modulator was then proposed and investigated as a derivative of the 3-branch waveguide switch. / Fabrication and experimental characterization of the three devices were also carried out. Key functional parameters were measured and compared with theoretical predictions. In general experimental results have borne out theoretical prediction. / Some calibration of the fabrication techniques employed, were also performed. An outline of the various experimental techniques used is also given. / Finally, some possible improvements are suggested for further work.

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