A color display apparatus for displaying a color video format signal comprising a two-dimensional screen on which light-beam sensitive three-primary-color luminous bodies are arrayed regularly in a predetermined direction, a generator for generating horizontal and vertical synchronizing signals from the video format signal, a light-beam deflector for scanning the two-dimensional screen with a signal light beam in synchronism with the horizontal and vertical synchronizing signals, and a modulator for modulating the intensity of the light beam in accordance with the color video format signal in synchronism with the scanning of the light beam in the predetermined direction.

Color display apparatus

A color display tube system comprising an electron gun for producing three co-planar electron beams, and including a main deflection system which in operation generates deflection fields of the self-convergent type, and an auxiliary deflection system which in operation generates a 45° magnetic 4-pole field facing the electron gun and moving the outer electron beams away from each other, and a 45° magnetic 4-pole field facing the display screen and moving the outer beams towards each other.

Color display tube system with reduced spot growth

A color TV display system with a circuit for generating in the line deflection coil halves a line-frequency sawtooth correction current whose amplitude varies at the frame frequency. The line deflection current in the line deflection coil halves is supplied by two line generators which are connected in series for direct current across the terminals of a supply source of DC voltage. The junction point of the generators is decoupled for line-frequency signals. A direct voltage which is substantially one-half of the supply voltage and a sawtooth modulation voltage at the frame frequency are both applied to the junction point.

Circuit arrangement in a display device for producing a line-frequency sawtooth current having an amplitude which varies at the frame frequency

Colour television display apparatus in which for correction of astigmatic deflection errors a correction current flows through the coil halves of at least one deflection coil unit, which current induces a second correction current in the other deflection coils so that two correction quadripolar fields are produced. The voltage produced by the induced current across each deflection coil half is zero and the deflection coil parts are toroidally wound on the core. The apparatus may be provided with phase-shifting networks.

Colour television display apparatus provided with a cathode-ray tube

A deflection apparatus comprising a cathode ray tube includes a pair of quadrupole arrangements (324, 424) for producing a pair of quadrupole fields in a beam path of an electron beam at different distances from a display screen (22'). In an embodiment of the invention, the first and second quadrupole arrangements and a main deflection field producing arrangement (55') cooperate to converge three electron beams, R, G and B, with one another, said quadrupoles being quadrupole doublets.

A deflection system with a pair of quadrupole arrangements

A color television display device provided with two systems of deflection coils formed with symmetrical coil halves and with a correction circuit for correcting the deflection errors caused by the anisotropic astigmatism of the systems of coils. The coil halves of at least one system of deflection coils are provided with at least one tapping which form part of the correction circuit in which in parallel with the number of turns located between one tapping and one end and a different tapping of a coil half a line and field frequency controlled current source or impedance and an impedance only controlled at the line frequency, respectively, are connected.

Versluis Johannes Willem

Papers

Color television display device