Abstract: A focal spot having an annular shape is often formed on the an (4) of an X-ray tube for analytic purposes. For the cooling of an anode it is known to force the cooling water to impinge on the anode with a flow profile having the same shape as the focal spot. In order to achieve this effect in the case of an annular focal spot, a circular delivery opening (36) is provided. In order to break up the steady boundary layer on the surface to be cooled, the impinging cooling water is forcibly split so as to flow into two directions. This is achieved by making the water flow via a distribution member 30 in which the circular delivery opening 36 is provided and by discharging the water via a discharge opening 40 which is situated within the circular delivery opening 40 and also via a return opening which is defined by the outer surface 42 of the distribution member 30 and the inner side of the discharge tube 16.

Abstract: The inner surface of a cathode ray tube is roughened by blasting the surface with a suspension which comprises radiation particles, the inner surface being irradiated in such a manner that it satisfies the inequalities 0.05 .mu.m<R.sub.a <0.5 .mu.m and R.sub.z <4 .mu.m and, preferably, 0.1 .mu.m<R.sub.a <0.2 .mu.m. The reflection at such a surface is comparable to the reflection at an etched surface. The method in accordance with the invention is safer and less harmful to the environment.

Abstract: In a flat display device, for example, a luminescent display a spacer structure (5) is provided between two substrates (1, 3). To this end a mask (9, 15) consisting, if necessary, of a plurality of layers is incorporated in a photosensitive material (8, 13). After exposure, development and removal of the mask, the desired spacer structure is obtained.

Abstract: In a flat display device, for example, a luminescent display a spacer structure (5) is provided between two substrates (1, 3). To this end a mask (9, 15) consisting, if necessary, of a plurality of layers is incorporated in a photosensitive material (8, 13). After exposure, development and removal of the mask, the desired spacer structure is obtained.

Abstract: A semiconductor device is provided with a polyimide film 21 between the encapsulating synthetic resin 16 and the passivating film 20. If a material having a high hardness (E-modulus.gtoreq.1.0.multidot.10.sup.10 Pa) is selected as the polyimide, the number of defects caused by variations in temperature is reduced.

Abstract: The master disc contains a substrate plate which is preferably provided with an optically detectable guide track and a recording layer of polysulphone such as poly(1-butene sulphone) to which, preferably, a colorant is added and in which an optically readable information track is provided by patterned exposure, a pit or groove being formed in the polysulphone layer. A matrix is formed by applying a metal layer to the polysulphone layer by means of an electroless deposition process and then, applying a further metal layer by means of an electrodeposition process or applying a curable synthetic resin layer together with a metal disc, after which the synthetic resin is made to cure.