Fast high-resolution micro-CT with exact reconstruction methods

We have constructed a helical trajectory X-ray micro-CT system which enables high-resolution tomography within practical acquisition times. In the quest for ever-increasing resolution, lab-based X-ray micro-CT systems are limited by the spot size of the X-ray source. Unfortunately, decreasing the spot size reduces the X-ray flux, and therefore the signal-to-noise ratio (SNR). The reduced source flux can be offset by moving the detector closer to the source, thereby capturing a larger solid angle of the X-ray beam. We employ a helical scanning trajectory, accompanied by an exact reconstruction method to avoid the artifacts resulting from the use of large cone-angles with circular trajectories. In this paper, we present some challenges which arise when adopting this approach in a high-resolution cone-beam micro-CT system.