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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.
21

Polymeric beam-steering 1xN fiber-optic switch

Jang, Chiou-hung 28 August 2008 (has links)
Not available / text
22

Design, analysis, and implementation of multi-port refraction based electro-optic switches

Zuo, Yiying, 1974- January 2006 (has links)
Electro-optic (EO) beam deflectors are voltage-controlled devices widely used for scanning and switching applications. For example, high-speed, low-loss optical switches aimed at future optical networks can be built on EO deflectors. Novel EO deflectors distinguish themselves with a much-improved steering performance, high-speed response and simple fabrication requirements. Patterned ferroelectric crystals such as LiTaO3 are first poled to provide the required prism shaped domain structures. The application of an electrical field across the entire crystal can then be used to drive the trajectory of the beam as it travels through the poled wafer. The electric field induces an index change of opposite magnitude on the adjacent domain regions in the EO device, causing the optical beam to refract at the interfaces. / Although rectangular geometry is extensively employed in EO devices, nonrectangular scanners have demonstrated better deflection performance. Two new nonrectangular geometries capable of further enhancing the deflection performance of EO beam scanners, proposed in this dissertation, were constructed. Their parabola and half-horn geometries provide 2-3 degrees of steering, which is 2-3 times greater than the steering provided by rectangular deflectors. / EO deflectors based on the parabola and the half-horn geometries, which can provide larger deflection angles, were built. These devices demonstrated a deflection angle of 3.1°, less than 5 dB of insertion loss from fiber to fiber, and -40 dB of crosstalk. / Two packaged optical switches using rectangular EO deflectors were demonstrated. By combining these EO deflectors with fiber collimators and high voltage packaging, high speed optical switches were built and characterized. The switch design was based on a 500mum z-cut LiTaO3 single crystal wafer fabricated using the domain inversion method. The 1x2 switch had a maximum deflection angle of 1.22° with an applied voltage of 1.1 kV and the 1x4 switch had a maximum deviation angle of 2.14°, with an applied voltage of 1 kV. The average insertion loss and crosstalk figures were 2.36 dB and -36 dB, respectively. The worst case switching time was 86 ns.
23

Fabrication and packaging of carbon-dioxide-laser-induced long-period fiber grating devices

Braiwish, Mohammad I. 05 1900 (has links)
No description available.
24

Optical two-wave mixing in iron-doped indium phosphide.

Peereboom, Nick C. (Nicolaas Christopher), Carleton University. Dissertation. Engineering, Electrical. January 1992 (has links)
Thesis (M. Eng.)--Carleton University, 1992. / Also available in electronic format on the Internet.
25

Novel concepts in the design and synthesis of organic nonlinear optical and electro-optic materials /

Bhattacharjee, Sanchali. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 169-180).
26

Design, analysis, and implementation of multi-port refraction based electro-optic switches

Zuo, Yiying, 1974- January 2006 (has links)
No description available.
27

HYBRID OPTICAL/DIGITAL PROCESSING APPROACH FOR INTERFRAME IMAGE DATA COMPRESSION.

ITO, HIROYASU NICOLAS. January 1982 (has links)
Image data compression is an active topic of research in image processing. Traditionally, most image data compression schemes have been dominated by digital processing due to the fact that digital systems are inherently flexible and reliable. However, it has been demonstrated that optical processing can be used for spatial image data compression, using a method called interpolated differential pulse code modulation (IDPCM). This is a compression scheme which functions analogously with conventional digital DPCH compression, except that the specific compression steps are implemented by incoherent optical processing. The main objective of this research is to extend IDPCM to interframe compression, design such systems, and evaluate the compression performance limitation under no channel errors, given the subjectively acceptable image quality by means of digital simulation. We start with a review of digital spatial and interframe compression techniques and their implications for optical implementation. Then, the technological background of electro-optical devices which has made possible hybrid optical/digital processing for image data compression will be briefly discussed. Also, a detailed description of IDPCM coding is given, along with the ways that IDPCM can be extended to interframe compression. Finally, two architectures of hybrid and optical/digital interframe compression are proposed, simulated, and evaluated in order to discover potential performances of optically implemented interframe compression systems. Excellent reconstructed image quality is obtained by the proposed adaptive hybrid (O/D) IDPCM/frame replenishment technique at an overall transmission rate of 3 Mbits/sec, average bit rate of 1.5 bits/pixel, and the average compression ratio of 5.2:1.
28

An optical switch.

Vlannes, Nickolas Peppino January 1975 (has links)
Thesis. 1975. B.S.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / Includes bibliographical references. / B.S.
29

Design and synthesis of organic chiroptical switches

Li, Jie 08 1900 (has links)
No description available.
30

Optoelectronic device simulation optical modeling for semiconductor optical amplifiers and solid state lighting /

Wang, Dongxue Michael. January 2006 (has links)
Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2006. / Buck, John, Committee Co-Chair ; Ferguson, Ian, Committee Chair ; Krishnamurthy,Vikram, Committee Member ; Chang, Gee-Kung, Committee Member ; Callen, W. Russell Jr., Committee Member ; Summers, Christopher, Committee Member.

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