Abstract: A shadow mask is formed by lapping a main mask and an auxiliary mask on each other. The auxiliary mask includes a porous portion having electron beam passage holes, nonporous portions situated individually at the opposite ends of the porous portion, a pair of skirt portions extending individually from the nonporous portions and lapped on the skirt portion of the main mask, and second beads formed individually on the skirt portions and overlapping first beads of the main mask. The height or width of the first beads and the second beads in a superposed portion in which the main mask and the auxiliary mask are lapped on each other is differentiated from that of the beads in non-superposed portions outside the superposed portion.

Abstract: A main lens is composed of a dynamic focus electrode, a first auxiliary electrode, a second auxiliary electrode and an anode, which are successively arranged in a direction of travel of electron beams. A sub-lens provided on a cathode side of the main lens is composed of a third grid, a fourth grid and a fifth grid. The first auxiliary electrode is connected to the fourth grid, and both are connected to a voltage supply terminal on a resistor near the fourth grid. A fixed focus voltage is applied to the third grid and fifth grid sandwiching the fourth grid.

Abstract: The present invention relates to a deflection yoke, and in particular, to an apparatus for correcting a mis-convergence and geometric distortion in a deflection yoke using a variable resistance, proving a more convenient way to adjust VCR by adjusting the current flowing in a comma-free coil using a variable resistance, instead of attaching a magnetic member as in the conventional method for the products associated with VCR (Vertial Green) properties.

Abstract: Horizontal line misconvergences produced at screen upper and lower portions, among rasters displayed by side electron beams are corrected without producing degradation in vertical deflection sensitivity so much and changing horizontal trapezoidal distortion. In a deflection yoke provided with a top-and-bottom pair of saddle-type horizontal deflection coils and a right-and-left pair of saddle-type deflection coils and mounted to and used in a color cathode ray tube having an in-line arranged electron gun, a pair of sub-cores is provided from side to side or above and below on the electron gun side of the deflection yoke. At least one pair of correction coils is wound around each of the pair of sub-cores.

Abstract: A color television display device comprising a deflection coil unit with a deflection coil for the vertical deflection which coil is divided into two coil halves. A balancing resistor by means of which the convergence can be corrected is in a parallel branch. A static convergence error introduced by this resistor owing to the non-zero inductance of the deflection coil is corrected by means for decreasing the voltage present across the balancing resistor during the trace period of the deflection current by a direct voltage in such a way that the voltage across the resistor is more decreased after the center instant of the trace period than before and that the correction current at and about said center instant is substantially zero. (FIG. 3).

Abstract: A line sweep magnetic deflection system is triggered to display ultrasonic echo impulses during line by line scanning of a body region. Each trigger impulse produces a nonlinear saw-tooth voltage waveform as a function of time which when converted to a corresponding current waveform in the deflection coil produces a constant line deflection velocity for accurate display of echo signals in spite of nonlinearities in the electron optics of the oscilloscope, for example. High gain differential amplifier means force the coil current to conform to the voltage waveform during active line trace, and deviations during retrace intervals cause the application of an overvoltage to the coil driver stage, blocking a normal operating supply voltage therefor, and rapidly driving the coil to its initial energy state, thereby enabling a higher line sweep frequency with consequent optimum display resolution.

Abstract: A high voltage regulating circuit has a cathode-ray tube, horizontal deflection means comprising a horizontal deflection output transistor and a horizontal deflection coil for generating a saw-tooth current therein, high voltage generating means connected with the anode of the cathode-ray tube for supplying a high D.C. voltage to the anode thereof and comprising a high voltage generating output transistor, a flyback transformer and a high voltage rectifier, a voltage source, a variable impedance means connected between the voltage source and the high voltage generating means, and a control signal supply means. The control signal is supplied to the impedance means to control the impedance thereof so as to control the voltage supplied to the high voltage generating means thereby maintaining constant the high D.C. voltage supplied to the anode of the cathode-ray tube.