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| A new transform pair has been introduced for the fan-beam image reconstruction[10]. This new integral transform plays the same role as the Hankel ( Fourier Bessel) transform in the parallel beam case and includes the Hankel transform as a special case. In this paper we develop this method for the equal-angle fan beam geometry. We call this new pair the General Hankel transform which gives transform and inverse transform from an object function f(r,beta) to fan beam projections R_beta(gamma). One member of the pair can be used to calculate projection data for simulation; the other can be used as an algorithm for fan beam reconstruction without interpolation in polar coordinates. Compared with other algorithms for fan beam reconstruction the general Hankel transform method is especially useful when f(r,beta) the image to be reconstructed, has only low frequencies in the theta angle direction and only few projections are available. |
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| Keywords:Image reconstruction, fan beam, tomography, Hankel |
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