Both the speed of acquisition and the spatial resolution of X-ray microbeam-based first-generation tomography depend on the size of the microbeam and on the steps that are employed during the step wise movement along the x-axis, as well as on the number of angular orientations that are employed in the scanning experiment.
The conversion of sinograms to tomograms can be performed analytically by means of the filtered back projection method (FBP), iteratively by different algebraic reconstruction techniques (ART, SIRT, etc.)[16] or by statistical algorithms such as the maximum-likelihood expectation maximization (MLEM) algorithm. In what follows, we compare the (dis) advantages of using the MLEM and FBP methods.