| The more rays cast per cycle (i.e., the smaller angle by which the scanner source rotates each time), the better image (the left column) reconstructed from the projection data, as demonstrated by the sinogram (the right column) in frequency domain. The symmetry property indicates that a 180-degree data collection cycle (half-scan) is sufficient to achieve full image reconstruction while an associated half-scan resonctruction algorithm is needed. Below used is the ellipsoidal Phantom model. |
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(1) 8 rays are cast per cycle.
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(2) 16 rays are cast per cycle.
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(3) 32 rays are cast per cycle.
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(4) 64 rays are cast per cycle.
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(5) 128 rays are cast per cycle.
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(6) 256 rays are cast per cycle.
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