Novel approaches for the use of Coded Apertures in high-energy high-resolution imaging systems

X-ray imaging with a camera is most commonly performed with a pinhole aperture; a single perforation within some opaque medium. Both the attainable resolution and the flux are limited by the perforation size, leading to an inherent compromise between the two in single-perforation apertures. Multi-perforation apertures, dubbed "coded apertures", overcome this compromise using a large number of small-sized perforations in a coded geometry. However, as sources decrease in scale and increase in energy (e.g. laser wakefield acceleration x-ray sources and neutrons generated during internal confinement fusion) the application of any form of pinhole aperture becomes less common. This is due to the large substrate thickness required for optical opacity coupled with the necessity for small perforations causing aspect ratio, manufacture, and implementation complications.

This project aims to increase the scope of use for coded aperture based imaging systems for high-energy high-resolution applications. This will be achieved by utilising secondary properties of existing coded aperture theory in novel approaches to reduce previous constraints such as substrate opacity, large detector area, and spectrally selective cameras. This will then be expanded to include the changes necessary to allow multi-MeV imaging of micron-scale objects and sources. During the project, the imaging system will be applied to x-ray radiography, tomography, and backscatter of objects, as well as imaging neutron implosions during fusion reactions. However, the possible applications could reach as far as medical imaging, laboratory astrophysics experiments, and scanning for port security.