The registration of a certain slice width depends on:
a/ selective activation and combination of detector signals into 4 channels.
b/ precise collimation which sometimes covers parts of the detectors.
Example A/ For 4X5 mm collimation the incoming radiation from the three innermost detectors on each side are summed up into slice B and slice C.
Example B/ For 4X1 mm collimation the next but innermost detectors on each side are partially covered by the collimators thus allowing only a 1 mm wide x-ray beam to hit the 1.5 mm wide detectors.
ct scan machines of detector