PhD Final Dissertation Defense - Ke Chen

12:00 pm on Wednesday, March 26, 2014
2:00 pm on Wednesday, March 26, 2014
8 Saint Mary's Street, Room 339
In conventional Computed Tomography (CT) systems, a single X-ray source spectrum is used to radiate object and the total transmitted intensity is measured to construct spatial linear attenuation coefficient (LAC) distribution. Such scalar information is adequate for visualization of interior physical structures, but additional dimensions would be useful to characterize the nature of the structures. By imaging using broadband radiation and collecting energy-sensitive measurement information, one can generate images of additional energy-dependent properties that can be used to characterize the nature of specific areas in the volume of interest.

In this thesis, we explore novel imaging modalities that use broadband sources and energy-sensitive detection to generate images of energy-dependent properties of a region, with the objective of proving high quality information for material component identification. We explore two classes of imaging problems: 1) excitation using broad spectrum sub-millimeter radiation in the Terahertz regime that uses the diffracted Terahertz (THz) filed to construct the spatial distribution of complex refractive indices at multiple frequencies; 2) excitation using broad spectrum X-ray sources and measurement of coherent scatter radiation to image the coherent-scatter form factors spatial distribution.