Sub-Diffraction Imaging using Superoscillatory Electromagnetic Waves

This thesis presents an investigation on imaging beyond the diffraction limit with superoscillatory electromagnetic waves. It begins with a survey on sub-diffraction imaging, which motivates the need for a new sub-diffraction imaging device which is free from drawbacks in devices which have heretofore been proposed. This work addresses this need through the design and demonstration of superoscillatory wave-based focusing and imaging devices. Through establishing a relationship between superoscillation and superdirectivity, a design procedure is formulated whereby antenna array theory is leveraged to design 1D and 2D superoscillatory waves. These waves are then physically synthesized or implemented as a filter in focusing and imaging systems at frequencies ranging from microwave to optical. Experimental characterization of these systems has led to successful demonstrations of sub-diffraction focusing and imaging, with working distances orders of magnitude farther than most other electromagnetic wave-based sub-diffraction imaging devices. In particular, the Optical Super-Microscope which achieves far-field sub-diffraction focusing has attractive merits to become a tool for general-purpose sub-diffraction optical microscopy. An investigation has also been conducted on superoscillatory waves in the time domain, which has resulted in the first reported demonstration of a superoscillatory temporal waveform, as well as a demonstrated improvement of radar range resolution beyond the Fourier transform limit.

Department dc:contributor.department

Electrical and Computer Engineering

Year dc:date.issued

2014

Author dc:creator

• Wong, Man Hon Alex

Advisor dc:contributor.advisor

• Eleftheriades, V. George

• Antenna Arrays
• Electromagnetics
• Imaging
• Microscopy
• Superoscillation
• Superresolution

Handle dc:identifier.uri

http://hdl.handle.net/1807/68356

OAI identifier oai:identifier

oai:utoronto.scholaris.ca:1807/68356