(FOV) The field of view is the maximum diameter of the area of the scanned object that is represented in the reconstructed image. It can also be the surface of the used detector.

(SFOV) The scan field of view is the area being scanned. This selectable scan factor is measured from a CT system isocenter to the most distant located edge of the patient.

See also Reconstruction Field Of View.

(DFOV / RFOV) The display field of view is a selectable scan factor measured from the center of the patient to the most distant located edge of the patient.

(RFOV) The reconstruction field of view is the size of the scan field of view (SFOV) that is reconstructed to form a CT image.

A calibration is a correction procedure that determines the relationship between the measured output of a system and the reference standard. Calibration procedures include scanning air or an appropriate test phantom.
The calibration of a CT system takes account of variations in beam intensity or detector efficiency in order to achieve best homogeneity within the field of view and the accuracy of CT numbers.

See also Calibration Factor and Acceptance Checking.