Filtered Backprojection in Compton Imaging using a Spherical Harmonic Wiener Filter with Pixelated CdZnTe

Journal Article · Fri Dec 18 00:00:00 EST 2020 · IEEE Transactions on Nuclear Science

DOI:https://doi.org/10.1109/tns.2020.3045878· OSTI ID:1763957

Shy, Daniel ^[1]; Chen, Zhuo ^[1]; Fessler, Jeffrey A. ^[1]; He, Zhong ^[1]

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1. Univ. of Michigan, Ann Arbor, MI (United States)

Filtered backprojection is an image reconstruction technique for Compton imaging that provides reasonably high resolution at much lower computational costs when compared to iterative methods. Here, this work applies a Wiener filter that has been derived for spherical harmonics on Compton imaging using the OrionUM pixelated CdZnTe imaging-spectrometer. To regularize the filter, an investigation is made into the power spectral density of the signal and noise to develop an appropriate spectral signal-to-noise ratio model for the restoration process. Experimental measurements were conducted with two 228Th sources placed 30° apart. The resulting filtered image of the two sources have an average full-width-at-half-maximum (FWHM) of 9.8° or 7.5° when using a mean squared error and structural similarity optimization approach respectively; an improvement from the 29.0° FWHM image when using simple backprojection.

• Research Organization: Univ. of Michigan, Ann Arbor, MI (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation
• Grant/Contract Number: NA0003920
• OSTI ID: 1763957
• Journal Information: IEEE Transactions on Nuclear Science, Vol. 68, Issue 2; ISSN 0018-9499
• Publisher: IEEE
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
Gamma-ray imaging
filtered backprojection
spherical harmonics
Wiener filter