The X-ray tube includes a cathode in a vacuum housing. The housing includes at least one metallic region and two current conductors. The conductors are lead into the vacuum housing through ceramic members designed as an electrical insulator. The ceramic insulators are connected to the metallic region so that heat is conducted from the current conductors to the ceramic insulators. The ceramics have a thermal conductivity greater than 20 W per mK. The ceramics may be made of a material from the group aluminium oxide, silicon nitride, aluminium nitride, or beryllium oxide.
