An x-ray tube has a stationary vacuum housing, in which are arranged an electron-emitting
cathode and a ring anode with an impact surface on which the electron beam, accelerated
by an electrical field, is incident, as well as a deflection system to focus and
deflect the electron beam. The ray exit window of the x-ray tube is round, lies
in the plane perpendicular to the central axis of the x-ray tube, and terminates
one side at the vacuum housing. The impact surface of the ring anode is beveled
and is aligned to the ray exit window. A diaphragm is provided in front of the
ray exit window that defines a circular opening for the x-ray radiation. The ring
anode is surrounded by an annular anode cooling arrangement.
