The invention relates to a
computed tomography scanner comprising a static radiator-
detector ring (10) which is composed of an odd number (n) of radiator-
detector elements (11, 12, 13, 14, 26), one unique radiator-
detector element (26) of which is movable relative to the remaining, jointly describing C-shaped radiator-detector elements (11, 12, 13, 14) such that the radiator-detector ring (10) is opened, wherein each radiator-detector element (11, 12, 13, 14, 26) has an
anode system (9) arranged for emitting X-rays which extends over an angle a of at least 0.9 x 360° / n on the circumference of the radiator-detector ring (10) and a detector (4) arranged for detecting X-rays which extends over an angle β of at least 0.95 x 360° / n within the same radiator-detector element (11, 12, 13, 14, 26), and each
anode system (9) is part of a radiator
system (18) comprising a plurality of
electron emitters (5, 25), each of which is designed to produce a focal point (BF ‑ , BF, BF + ) on the
anode system (9) in one of at least three selectable positions in cooperation with an
electrode system (21).