Apparatus and method for computed tomography scanning using halfscan reconstruction with asymmetric detector system

A method of generating tomographic image data for an object, said method comprising:

• providing a radiation source for directing radiation through the object;
• providing an array of detectors for receiving the radiation from the object to acquire fan beam projection data used to generate the image data for the object, the array of detectors and the radiation source being rotatable about a center of rotation in the object through a plurality of projection angles to acquire the fan beam projection data, the ends of the array of detectors defining a fan angle having an apex defined by the radiation source, a line connecting the radiation source and the center of rotation dividing the fan angle into a first partial fan angle and a second partial fan angle, the first and second partial fan angles being unequal, wherein each line connecting each detector in the array of detectors and the radiation source defines a detector angle .phi. with the line connecting the radiation source and the center of rotation, the smaller of the first and second partial fan angles being .phi..sub.MIN and the larger of the first and second partial fan angles being .phi..sub.MAX ;
• and
• generating the slice of image data using a subset of a complete set of fan beam projection data for the slice, wherein the complete set of fan beam projection data for the slice comprises all of the fan beam projection data available from a complete revolution of the radiation source and the array of detectors about the center of rotation.