Investigator of Coherence Imaging, Photon Migration, and Short-Pulse Image Processing

摘要

A theoretical investigation was made into the angular correlation that exists between two plane waves propagating through a scattering medium. Comparisons were made with the coherence existing between the angular correlation and the correlation of the exiting waves with a reference wave. Such studies are important to understanding how a wave field can be recovered after propagation through a scattering medium. A new concept, that of spatial filtering time gating, was investigated. This idea enables propagation through scattering media to be studied in a simple way unencumbered by the complexities of short coherence length interference. New concepts in confocal imaging were explored relating this process to volume holography and to synthetic aperture imaging. Confocal imaging theory was reformulated in the broadest possible way, giving rise to a basic theory of confocal imaging that encompasses all confocal imaging processes in their many diverse forms including the novel forms developed here. A new method of recording scattered light was developed. This method is based on up-conversion in non-linear crystals and records only the light component in which the propagation vector is aligned along some preferred axis. This method will further improve the capability for imaging of objects embedded in scattering media. Phase conjugation methods were employed in a novel way to detect objects embedded in scattering media.