Use of an array of three off-axis zone plates for large field of view gamma ray imaging


Journal Article

A coded aperture consisting of a planar array of three off-axis zone plates oriented at 120° with respect to each other has been used to image gamma-ray sources up to ten inches in diameter. The zone plates do not have a common axis, and the high frequency zones of each zone plate are located in the central region. The maximum radius and fringe spacing are chosen so that the spatial frequency bandpasses for the individual zone plates do not overlap, and a hexagonal array of holes is used as a sampling screen (half-tone) to shift the object spectrum into the bandpass of the three zone plates. The aperture configuration permits more uniform sampling of a large object as compared with a system consisting of a single large off-axis zone plate. Design parameters are discussed, particularly those related to the imaging of bar phantoms and the generation of coherent artifacts. Reconstructed images of gamma-ray sources using the three zone plate system are presented. © 1974 SPIE.

Full Text

Duke Authors

Cited Authors

  • Whitehead, FR

Published Date

  • May 1, 1974

Published In

Volume / Issue

  • 43 /

Start / End Page

  • 3 - 10

Electronic International Standard Serial Number (EISSN)

  • 1996-756X

International Standard Serial Number (ISSN)

  • 0277-786X

Digital Object Identifier (DOI)

  • 10.1117/12.953883

Citation Source

  • Scopus