Method and device for determining images from X-ray projections

A device for determining attenuation coefficients for an object using a movable X-ray source and a detector, which is provided for recording projections, the device comprising:

• a hardware computing unit configured to:
• specify a trajectory path for the movable X-ray source;
• specify positions on the trajectory path for determining a derivative of projections recorded by the detector;
• specify a plurality of scanning positions for each of the specified positions;
• numerically calculate a projection derivative in relation to the trajectory path for each of the positions using the projections recorded for the associated plurality of scanning positions;
• and
• determine attenuation coefficients for the object from the calculated projection derivatives using a theoretically exact or approximate rule for a reconstruction;
• the X-ray source operable to follow the specified trajectory path;
• and
• the detector operable to record a projection for each scanning position,
• wherein an interval between adjacent scanning positions that belong to the same plurality of scanning positions is smaller than an interval between adjacent scanning positions that belong to different pluralities of scanning positions.

In a non-transitory computer-readable storage medium that stores instructions executable by a computing unit to determine attenuation coefficients for an object using a movable X-ray source and a detector, which is provided for recording projections, the instructions comprising:

• specifying a trajectory path for the movable X-ray source;
• specifying positions on the trajectory path for determining a derivative of projections recorded by the detector;
• specifying a plurality of scanning positions for each of the specified positions;
• following the trajectory path with the X-ray source and recording a projection for each scanning position of the pluralities of scanning positions;
• numerically calculating a projection derivative in relation to the trajectory path for each of the specified positions using the associated recorded projection for each scanning position of the pluralities of scanning positions;
• and
• determining attenuation coefficients for the object from the calculated projection derivatives using a theoretically exact or approximate rule for a reconstruction,
• wherein an interval between adjacent scanning positions that belong to the same plurality of scanning positions is smaller than an interval between adjacent scanning positions that belong to different pluralities of scanning positions.