Abstract: In order to enhance the dissipation of heat, a metal structure is provided between an anode target layer and a support for the anode target layer in an X-ray tube. In the case of a target transmission tube, notably the dissipation of heat to the window wall is enhanced, whereas in the case of an anode target layer provided on a suitably thermally conductive anode body, the dissipation of heat to said body is enhanced.

Abstract: An X-ray collimator in an X-ray analysis apparatus, consisting of plates of X-ray absorbing material, for example tungsten, which are arranged transversely of the X-ray beam. The plates are identical and provided with a pattern of rows and columns of rectangular openings 40, 42 which have a vertical period p.sub.1 and a horizontal period p.sub.2. The openings take up an opening fraction t.sub.1 and t.sub.2 of the periods p.sub.1 and p.sub.2, respectively. The plates are arranged in the collimator in a series in which the ratio between two successive distances (d.sub.i, d.sub.i+1) between the plates of the series is equal to the given opening fractions t.sub.1 and t.sub.2 of the periods p.sub.1 and p.sub.2, respectively. It has been found that all directions in the X-ray beam are then intercepted except for the direction to be collimated. Moreover, this configuration also enables transverse collimation.

Abstract: An X-ray diffraction device comprises a water-cooled X-ray tube which exhibits a line focus as well as, after rotation through 90.degree., a point focus. Contrary to customary X-ray tubes, the cooling water is not supplied via the housing (12) in which the X-ray tube is mounted, but the cooling water connections (52, 54) are provided directly on the X-ray tube at the same side of the robe where the high-voltage connector (16) is provided. As a result, rotation of the robe upon changing over from a line focus to a point focus is not hampered by cooling water connections inside the housing of the tube. An additional advantage of this method of supplying the cooling water resides in the fact that the robe base (56) can also be cooled via these ducts. The base would otherwise become inadmissibly hot due to the loss heat from the filament (60).

Abstract: In order to enhance the dissipation of heat, a metal structure is provided between an anode target layer and a support for the anode target layer in an X-ray tube. In the case of a target transmission tube, notably the dissipation of heat to the window wall is enhanced, whereas in the case of an anode target layer provided on a suitably thermally conductive anode body, the dissipation of heat to said body is enhanced.

Abstract: An electron-optical system directs an electron beam which emanates, for example from a line-shaped or annular emissive cathode element, onto an anode target face in a collimated fashion so that a large part of reflected electrons is incident on the target face again, thus contributing to the generating of X-rays. The construction of the electron-optical system and the high degree of re-incidence of scattered electrons allows for a minimum distance between the anode target face and the exit window. A filament of the cathode may be constructed so as to achieve an optimally uniform operating temperature over a comparatively large part of its length.