Abstract: A high-speed current switch has complementary switching stages for collectively producing a square-wave output current. Spurious currents and charging delays caused by intrinsic capacitances in one stage substantially cancel those in the other stage.

Abstract: A circuit arrangement for operating a semiconductor light source, includes input terminals for connecting a supply voltage, an input filter, a converter having a control circuit, and output terminals for connecting the semiconductor light source. The circuit arrangement is provided with a voltage detector for detecting the output voltage at the output terminals.

Abstract: A cathode ray tube having a deflection unit, the play between the deflection unit (11) and the envelope (4) being different for two perpendicular (x and y) directions. This enables the tilt of the deflection unit relative to the envelope to be greater in a direction than in a direction at right angles to said direction. By virtue thereof, the distance between the deflection unit and the electron beams can be reduced, so that the deflection requires less energy and can be improved.

Abstract: In order to find the position of the boundary between transmitted codewords, in a receiver a reliability measure for two possible positions are compared. If a relative difference measure of these reliability measure exceeds a predetermined threshold value, the reliability measure indicating the largest reliability corresponds to the correct position of the boundary between the codewords.

Abstract: The device comprises a Wheatstone bridge with at least four magnetoresistive elements (1a, 1b, 1c, 1d) on a substrate (15), each magnetoresistive element comprising at least one sensitive portion (13) comprising successively a first ferromagnetic layer (19) having a magnetic easy axis (27) extending in a first direction, a non-magnetic layer (21) and a second ferromagnetic layer (23) having a magnetic easy axis (29) extending in a second direction that is different from the first direction. The sensitive portions (13) have mutually parallel sensitive directions that are parallel to a third direction (X). Each magnetoresistive element (1a, 1b, 1c, 1d) is associated with a current conductor (35a, 35b, 35c, 35d) provided in the immediate vicinity of that magnetoresistive element. The first direction (27) is canted through an acute angle with respect to the third direction (X), and the second direction (29) is canted in the opposite sense through an acute angle with respect to the third direction.

Abstract: A color display device having a color display tube with a display screen, comprising an electron gun for generating three co-planar electron beams, and a deflection system which, in operation, generates deflection fields for scanning the display screen, and an element influencing the landing angle of the outermost beams, for example an element generating, in operation, a 45.degree. magnetic 4-pole field, and comprising a correction device which supplies a signal to the element influencing the landing angle, which signal is derived from the video information (for example a signal which is proportional to the strength of the instantaneous beam current) in order to remedy landing errors caused by space-charge repellence between beams.

Abstract: A vacuum device has an envelope and a getter assembly mounted within the envelope. The getter assembly includes a reservoir for containing getter material and a deflector having a surface located opposite the getter material and is oriented to deflect the getter material in a predetermined direction within the vacuum device. The deflector surface has raised and/or depressed portions, such as ribs or undulations, in the direction of diffusion of the getter material. These portions reduce the accumulation of getter material on the deflector during getterfiring, resulting in a much reduced likelihood that getter material particles may break loose from the deflector. By preventing loose particles within the vacuum device, the possibility of a short-circuit in the vacuum device is reduced.

Abstract: In Deformed Helix Ferro-electric liquid crystal display devices (DHFLCDs) the memory effect in video applications is interrupted by adapting the data voltages of matrix displays based on MIMs or TFTs, dependent on the data in a previous frame, so that the polarization within a cell always switches to a fixed value (zero). In other types of displays (based on diodes) or for less rapid applications, the polarization can also be readily set at this value.

Abstract: Semiconductor device with a semiconductor cathode having an emissive part (pn junction) separated from a contact part which has locations at which a controlled breakdown occurs on a contact part metallization at excessive voltages, so that, during manufacture and operation, the emissive part in an election tube is protected from damage.

Abstract: A circuit arrangement for driving a light source includes input terminals (T1, T2) for deriving a supply current from a supply source; a circuit I for generating a control signal S; a circuit II, provided with a converter which is fitted with at least one switching element (13) and with a control circuit (17) which triggers the switching element with high frequency in a manner which is dependent on the value of the control signal S; a circuit III for generating a voltage Sc which is a measure for an instantaneous value of a supply voltage delivered by the supply source, the voltage Sc acting as a reference signal which causes the circuit I to generate a control signal S which lies alternately in a first range and in a second range, and the circuit II causing the drawing of a comparatively strong supply current (Iv1) at a value of the control signal S which lies in the first range, and the drawing of a comparatively weak supply current (Iv2) at a value of the control signal S which lies in the second range; an

Abstract: An electric field measurement system for precisely measuring low frequency electric fields includes a capacitive antenna having two parallel conductive plates (11, 12). The potential between the plates is a measure of the electric field present. A high impedance element (13) supplies the potential between the plates to an electro-optical converter (14) which converts the potential into an optical signal. The optical signal is coupled into an optical fiber (20) which transports the optical system to an optical-electrical converter (30), where the optical signal is converted into an electric signal, which is measured by a measurement device (31), e.g. a spectrum analyzer. The use of an optical fiber avoids disturbances of the field to be measured. The dimensions of the plates of the capacitive antenna, preferably, are only a few centimeters, thereby minimizing the influence of the antenna on the field to be measured.

Abstract: To test a cathode ray tube or an apparatus comprising a cathode ray tube, a part of the electron gun is heated by means of high-frequency electromagnetic radiation. By virtue thereof, the warm-up period, that is the time which, after turning on the cathode ray tube, must elapse before the testing operation can be carried out, can be reduced, for example, from approximately 30 minutes to approximately 2 minutes.

Abstract: A color display device including a shadow mask and a correction deflection system for correcting landing-errors. The correction deflection system comprises first and second correction deflection devices which are arranged one behind the other in the direction of the electron beams and are energizable in opposite senses so that the first correction deflection device generates a dipole field deflecting the three electron beams away from the longitudinal tube axis, and the second correction deflection device generates a dipole field deflecting the three electron beams towards the longitudinal tube axis, or conversely.

Abstract: A data storage unit comprises a housing, an information disc which is centrically rotatable about an axis of rotation, and an electrical drive unit for driving the information disc. A bearing supports the information disc and the rotor relative to the housing and a scanning unit is provided for cooperation with the information disc. The housing includes two plane-parallel main walls which are oriented transversely of the axis of rotation, which each have a contour at least substantially similar to that of the information disc, and which are interconnected by smaller side walls. The housing forms a cartridge accommodating the information disc, the electrical drive unit and the scanning unit. The information disc is disposed in a plane intersecting the electrical drive unit and the scanning unit is situated between the information disc and one of the main walls.

Abstract: A switched bridge circuit includes a low voltage to high voltage interface which selectively controls an input to a high side switch. A controller compares the voltage across the interface, the state of the high side switch, and the output of the circuit. If hard switching is detected by the controller, it latches the voltage across the interface thus keeping the high side switch on to allow the hard switching to occur. If soft switching is detected, the high side switch is kept off. A source follower is used to drive the high side switch so that the circuit output follows the interface output thereby avoiding oscillation. A falling edge detector for the output of the circuit uses the inherent parasitic capacitance of a high voltage device which also forms a bootstrap diode. When the output drops, the parasitic capacitance feeds a resistance which causes a driver to actuate. A second falling edge detector uses the inherent parasitic capacitance of the level shifter switch which is another high voltage device.

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: A method of printing a pattern on plates for flat display devices, in which method, in succession, a raised pattern is provided, which is then subjected to a printing process by means of an unpatterned screen-printing screen. For example, a pattern of phosphor dots or electrodes can be provided in this manner. It is also possible to make partitions, which form channels or cells on a plate for a plasma display device or PALC display device.

Abstract: A description is given of a method of providing an adhesive silver layer on a glass substrate, in which method the glass surface is activated, whereafter a first silver layer is provided from an electroless silver bath and reinforced by means of a second silver layer which is electrodeposited thereon from a cyanide-free bath comprising ammonia as the complexing agent for silver ions. The method can very suitably be used for silver-plating glass plates, as used in thin gas-discharge displays or thin electron displays, for example selection plates or control plates.

Abstract: A deflection unit having a hollow synthetic material coil support within which a line deflection coil system is arranged, which line deflection coils are connected in an electric circuit to a line balance coil arrangement comprising a cylinder which is provided with two sub-coils and within which a magnet core is movably arranged. The coil cylinder is secured to the coil support and is provided with an arrangement of metal (connection) strips which ensure a direct connection between the balance coil lead-outs, the line deflection coils and a tap.

Abstract: The display device includes a vacuum-tight envelope having a transparent front wall which is provided with a display screen. The display device comprises an internal selection structure (67) which is provided with holes and with a plurality of electrodes for addressing desired pixels on the display screen. The display device is provided with connection elements (71, 72) which each comprise a springy end portion (73, 74), which contacts an electrode (61, 62) on the selection structure (10), and which connection elements further comprise a feed-through portion (75, 76) to make an electric connection, through a wall of the envelope, between the electrodes (61, 62) and a voltage source situated outside the envelope. Preferably, the springy end portion (73, 74) includes a material which retains its springiness up to temperatures of at least 450.degree. C. for example a spring steel, and the material of the feed-through portion (75, 76) is adapted to the expansion of the material of the envelope.