Hitachi, Ltd.

Hitachi Media Electronics Co., Ltd.

Hitachi Mizusawa Electronics Co.

Kooji Fukuma

Soichi Sakurai

Nobutaka Okuyama

Yoshio Satoh

Hiroshi Yoshioka

Masao Obara

Naoki Ito

Atsushi Takeyama

Yoshihiro Obara

A color cathode-ray tube which includes a deflection yoke having a convergence correcting device and an electron gun provided to the deflection yoke for generating a multiplicity of electron beams. In the deflection yoke, a vertical deflection coil is made up of at least a pair of saddle type coil halves each divided into at least first and second coil parts, the first coil parts of the coil halves and the second coil parts thereof are connected respectively mutually in series or parallel, a subcore having a vertical auxiliary deflection coil is provided on a side of the electron gun, the vertical auxiliary deflection coil is made up of first and second correction coils for generating 4 polar magnetic field components which are directed at least opposite to each other, a series circuit of a first resistor and the first correction coil is connected in parallel to a series circuit of a second resistor and the second correction coil to form a parallel circuit, the parallel circuit is connected in series with the vertical deflection coil, a shunt circuit is provided for shunting a current flowing through the second coil part to supply the shunted current into the first and second correction coils to thereby cause a predetermined imbalance between the currents flowing through the first and second correction coils, when an area of a display screen other than a predetermined range in a vertical direction is subjected to a vertical deflection. Thereby horizontal and vertical line misconvergences can be corrected.

Deflection yoke and cathode-ray tube apparatus comprising the same

A deflection yoke attached to a color cathode ray tube forming multiple electron beams arranged in line, and in particular a deflection yoke having convergence correction apparatus. Circuit components such as a plurality of resistors, variable resistors, and diodes are connected in parallel with vertical deflection coils. A part of a vertical deflection current flowing through the vertical deflection coils is diverted to the circuit components. Furthermore, the amount of the diverted current is made adjustable so that it will differ between a former part of a vertical deflection period and a latter part thereof. As a result, horizontal line misconvergence at upper and lower ends of the screen can be completely corrected.

Deflection yoke and cathode ray tube having the same

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Yokohama, Japan

Kooji Fukuma