Abstract: A color selection means is described in which the mask (50) is stretched under tension and connected to a support frame. The support frame accurately determines the mask contour, while the mask is connected to this frame in a flexible way by mechanical means so that differences in expansion behavior of the mask and the frame can be handled. These connection means can be either lugs or resilient elements (59). Such a color selection means may be used in a color display tube having an at least substantially flat display screen.

Abstract: Method of providing a pattern of apertures and/or cavities in a plate of material which is suitable for powder blasting, or of cutting pieces from a plate (2) of such a material by means of powder blasting, using a non-metal layer of blast-resistant material (3) as a mask which is patterned while or after it is fixedly provided on the surface of the plate.

Abstract: A blast system for processing components by means of abrasive particles, comprising a hopper (1) for abrasive particles (2), a mixing device (3) formed by a mixing chamber (9) into which an HP-air pipe (10) issues and which in its turn issues into a blast pipe (11), a transport line (5) between the hopper and the mixing chamber, through which line the abrasive particles are transported from the hopper to the mixing chamber, means (6) for generating HP-air (P) which is supplied to the mixing chamber through the HP-air pipe for obtaining a mixture of air and abrasive particles issuing from the blast pipe, and a transport mechanism (4) for transporting the abrasive particles through the transport line. To obtain an energy-efficient system suitable for mass manufacture, the invention is characterized in that the system operates at an absolute pressure (P) of the HP-air of between 2 and 4.5 bar, while a ratio d.sub.1 /d.sub.2 of a smallest diameter d.sub.

Abstract: The invention relates to a magnetic clamping device with a clamping body (1) comprising a cylinder plate (2) of non-magnetizable material provided with cylinders (5), a clamping plate (3) of non-magnetizable material situated at one side of the cylinder plate, a closing plate (4) situated at the other side of the cylinder plate, and pistons (9) made at least partly from magnetic material which are movable in the respective cylinders, which clamping body is further provided with channels (13, 14) to which a fluidic pressure source can be connected for the simultaneous movement of the pistons in the cylinders towards and away from the clamping plate. To improve the magnetic clamping action, all magnetic pistons (9) are fastened to a common piston plate (8). This ensures that all magnetic pistons, when energized, will exert their magnetic influence on the object to be clamped.

Abstract: A display device includes: a rear wall (4); a display panel (3) spaced from the rear wall (4) and a display screen (7) having a pattern of phosphor pixels; an addressing structure (100) disposed intermediate the rear wall (4) and the display panel (3) for addressing the display screen (7); and an aperture spacer plate (101); wherein, the spacer plate (101) includes a glass material having an electrical resistance of log R at 250.degree. C..gtoreq.8. The spacer plate (101) including a glass material having an electrical resistance of log R at 250.degree. C..gtoreq.8 reduces the charging of the spacer plate walls and improves uniformity of phosphor brightness. The spacer plate may further comprise a glass having a lower alkali mobility less than sodium lime glass.

Abstract: A method of providing a plurality of cavities and/or apertures in a plate or layer wherein, after the plate or layer has been provided with a mask having a plurality of apertures arranged in a pattern, at least one jet of abrasive powder particles is moved relative to the plate. On its exposed surface, the mask is provided with a coating which prevents substantial mechanical stresses from being generated in the mask during the process by the jet of powder particles.

Abstract: A method of providing a plurality of cavities and/or apertures in a plate or layer wherein, after the plate or layer has been provided with a mask having a plurality of apertures arranged in a pattern, at least one jet of abrasive powder particles is moved relative to the plate. On its exposed surface, the mask is provided with a coating which prevents substantial mechanical stresses from being generated in the mask during the process by the jet of powder particles.

Abstract: Picture display device includes a display unit having a vacuum envelope which is provided with a transparent face plate with a luminescent screen and a rear plate. The display unit includes a plurality of juxtaposed sources for emitting electrons, a plurality of electron transport ducts cooperating with the sources and extending substantially parallel to the face plate for transporting the electrons in the form of electron currents, and an active selection structure for withdrawing each electron current at predetermined locations from its transport duct and for directing the current towards desired pixels of the luminescent screen.The picture display device further includes a video signal processing circuit for receiving an incoming video signal having a given line number, for processing the video signal to a video signal which is suitable for the luminescent screen, and for applying the processed video signal to a video drive circuit coupled to the sources.

Abstract: A low-energetic charged particle beam, involving only a slight space charge effect, can be obtained by high-frequency deflection of a charged particle beam before deceleration. Using a deceleration element provided with curved surfaces and a slit-shaped aperture, a focusing effect is obtained so that the charged particle beam is imaged along a linear path on a target surface. For implantation of a semiconductor substrate, a uniform and shallow implantation can be achieved at adequate speed by means of a low-energetic ion beam obtained in the above manner.