Disclosed herein are a high-voltage generator for an x-ray source, an x-ray gun, an electron beam apparatus, a rotary vacuum seal, a target assembly for an x-ray source, a rotary x-ray emission target, and an x-ray source. These various aspects may separately and/or together enable the construction of an x-ray source which can operate at energies of up to 500 kV and beyond, which is suitable for use in commercial and research x-ray applications such as computerised tomography. In particular, the high-voltage generator includes a shield electrode electrically connected intermediate of a first voltage multiplier and a second voltage multiplier. The electron beam apparatus includes control photodetectors and photo emitters having a transparent conductive shield arranged therebetween. The rotary vacuum seal includes a pumpable chamber at a position intermediate between high-pressure and low-pressure ends of a bore for a rotating shaft. The rotary target assembly is configured such that when a torque between a bearing housing and a vacuum housing exceeds a predetermined torque, the bearing housing rotates relative to the vacuum housing. The rotary x-ray emission target has a plurality of target plates supported on a hub, the plates being arranged on the hub to provide an annular target region about an axis rotation of the hub. The x-ray gun is provided with a shield electrode maintained at a potential difference relative to the x-ray target different to the electron beam emission cathode.

The disclosure relates, inter alia, to a rotary anode bearing assembly for an X-ray tube comprising at least one bearing outer ring and rolling elements arranged within the at least one bearing outer ring, which rolling elements roll on the at least one bearing outer ring and enclose a radially inner receiving space for receiving a rotor of an X-ray tube; comprising a bearing housing in which the at least one bearing outer ring is mounted, wherein the bearing housing circumferentially surrounds the at least one bearing outer ring. The rotary anode bearing assembly according to the disclosure includes an end face of at least one bearing outer ring or of a caulking ring axially adjoining the bearing outer ring is caulked to an end face of the bearing housing by plastic deformation of material of the bearing housing and/or of the bearing outer ring and/or of the caulking ring.

An X-ray tube bearing assembly may include a bearing housing including an accommodating cavity; and a bearing core accommodated in the accommodating cavity. The bearing housing may include first and second portions. The second portion surrounds and forms a portion of the accommodating cavity to accommodate the bearing core. The first portion extends out of the second portion and surrounds and forms another portion of the accommodating cavity, and the other portion of the accommodating cavity forms an accommodating hollow cavity. The first portion may have a different structural rigidity to that of the second portion.