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Filters for three-dimensional limited-angle tomography.

B Schorr·D Townsend
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Abstract

One approach to the three-dimensional, tomographic reconstruction of data from a planar dual-detector stationary positron camera necessitates frequency-space filtering of the image obtained from back-projection. It is therefore useful to have a closed-form expression for the appropriate filter, but the derivation is complicated by the fact that the camera measures only a limited angular range of projections. Nevertheless, suitable expressions can be obtained and are here derived for detectors of rectangular and circular cross-section.

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B Schorr, D Townsend. 1981. Filters for three-dimensional limited-angle tomography.. https://doi.org/10.1088/0031-9155%2F26%2F2%2F009

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