Physics Faculty Seminar: Correlation Structure in Scattered Light: Opportunities for Imaging, Instrument Design, and Material Characterization

April 28, -
Speaker(s): Michael Gehm (Duke ECE)
"Correlation Structure in Scattered Light: Opportunities for Imaging, Instrument Design, and Material Characterization"

As light is scattered by a random medium, the necessarily finite complexity of the scattering material induces correlations in how light incident from points lying within a given angular neighborhood is redirected by the scattering. As a result, the scattered light---although appearing scrambled---retains a 'memory' of some details of the incident light. This is known as the 'angular memory effect' and is of both fundamental interest and great utility.

First developed by astronomers in the era prior to adaptive optics, 'angular memory effect imaging' is a technique that makes use of the effect to form images of objects obscured by thin scattering layers (such as the turbulent atmosphere in astronomy) and which has seen continued refinement and development in recent years to take advantage of detector technology advancements and to extend the applicability to new areas: including imaging through layers of cells or even around a corner using the scattering properties of the paint on the wall.

This angular memory effect imaging method, however, has a number of highly specific constraints that limit its range of applicability. We can interpret many of these limitations as arising from an apparent loss of coherence in the field. For the majority of my talk I will discuss... Please see the Physics website for complete description.
Sponsor

Physics

Contact

Ryman, Cristin
919-660-2491