| Pitch and Noise |
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| l | To reconstruct
image, projections must be |
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| collected
over 180 gantry rotation and fan angle of |
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| x-ray beam (45
), about 2/3 of spiral |
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| l | Since
reconstruction algorithms need fixed |
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| number of
projections to make image and since |
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| pitch only
affects how these projections are |
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| distributed in
spiral, not the number of projections, |
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| pitch does not
affect noise |
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| l | No difference
between SS and MS |
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