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Digital X-ray laminography is a technique for generating sectional images of an object, using an X-ray source and detector that move in opposite directions in planes above and below the object. However, motion of the X-ray source and detector during acquisition causes blurring in the projection images, which in turn leads to blurred reconstructions. To prevent these motion artifacts, both the source and detector need to be still during the X-ray pulse which leads to longer acquisition times. In this paper, we consider a system for continuous digital laminography in which the X-ray source is continuously moving and emitting, which would allow for a higher rotation speed. The inherent motion related blurring in the projections is modeled in the reconstruction algorithm. A preliminary simulation experiment comparing the classical digital laminography with the proposed continuous technique indicates that a higher reconstruction quality can be achieved near the rotation center and less streak artifacts are present, at the cost of a decreasing tangential resolution with increasing distance from the rotation center.

In medical imaging, Chest Tomosynthesis (TS) is a form of limited angle tomography that allows to compute section images of a patient, in planes parallel to a flat panel detector placed behind the patient. Projection images are acquired using an X-ray tube that moves on a linear path with respect to the stationary detector. An important cause of artifacts in TS images are errors in the assumed geometrical setup of the system, especially the orientation of the X-ray tube path with respect to the detector. In this paper, we present a method for correcting errors in the acquisition geometry without the need for a calibration phantom. The method is evaluated on simulation data and experimental acquisitions and proves to substantially reduce reconstruction artifacts caused by geometry mismatches.

An important design aspect in tomographic image reconstruction is the choice between a step-and-shoot protocol versus continuous X-ray tube movement for image acquisition. A step-and-shoot protocol implies a perfectly still tube during X-ray exposure, and hence involves moving the tube to its next position only in between exposures. In a continuous movement protocol, the tube is in a constant motion. The angular integration of the rays inherently produces blurred projections. Conventional reconstruction from such projections leads to blurred reconstructed images, and therefore the projection angles are kept small. Important advantages of a continuous scanning protocol are shorter acquisition times and less demands on modality construction from a mechanical point of view. In this work, the continuous protocol is extended with continuous projections, in which the X-ray source is continuously emitting X-rays over larger angles. The focal spot motion can no longer be ignored and is modeled in the reconstruction. The reconstruction quality is compared with the equivalent step-and-shoot counterpart showing improved results for region of interest tomography.