Abstract: In an X-ray tube for an X-ray analysis apparatus an optimized minimum working distance is achieved, together with an adequately high radiation yield, by integrated optimization of the radiation end of the tube, the position and the mounting of the exit window, and the electron-optical configuration in the tube. This results in an X-ray tube having a conical end, an angle of cone of approximately 45.degree. and the use of the cone as such in the electron-optical system of the tube. Exact determination of the anode position relative to a reference face outside the tube enables exact positioning of each individual tube in an analysis apparatus.

Abstract: The electron-emissive element in an X-ray tube is constructed so as to be loop-shaped so that an electron target which is also loop-shaped can be formed on an anode. Notably for target transmission tubes having an integrated window-anode element, a substantial reduction of the window temperature can thus be achieved. Inter alia because of the lower temperature gradients, the window can be constructed to be thinner; however, its service life is substantially prolonged and the radiation efficiency of the tube is increased.

Abstract: The anode connections in a gas-filled X-ray detector are mounted so as to extend transversely of the anode wire so that a substantial saving as regards space is achieved. In order to reduce field inhomogeneities in the ionization space, there may be provided a field profile bush which partly encloses the anode wire and field bushes may be arranged around the anode connection pins.