Matsushita Electric Industrial Co., Ltd.

Matsushita Toshiba Picture Display Co., Ltd.

Matsushita Electric Ind. Co., Ltd.

Etsuji Tagami

Hiroshi Sakurai

Katsuyo Iwasaki

Akitsugu Ishii

Shunichi Miyazaki

Kazuo Nakano

Kenichiro Taniwa

Hiromi Wakasono

Toshihiko Shichijyo

In the vicinity of an end on the side of a large diameter portion of a deflection device, a pair of first permanent magnets for converging three electron beams in an X-axis direction and a pair of second permanent magnets for diverging them in the X-axis direction are provided. Inclination coefficients Kand Kof the distribution curve near the Z axis on the X axis of the Y-axis direction magnetic flux density of the magnetic fields respectively formed by the pair of first permanent magnets and the pair of second permanent magnets satisfy K/K&#x3c;10 in at least one location within a range of 3 to 13 mm on the side of the phosphor screen with respect to a reference line in the Z-axis direction. An inclination coefficient Kof the distribution curve near the Z axis on the X axis of the Y-axis direction magnetic flux density of a combination magnetic field formed by the pair of first permanent magnets and the pair of second permanent magnets and an inclination coefficient Kof the distribution curve near the Z axis on the Y axis of the X-axis direction magnetic flux density of the combination magnetic field are both larger than 1.5 (Gauss/cm) in at least one location within the above-noted range. This achieves excellent spot shapes, thus making it possible to reduce change in convergence characteristics due to temperature variation and pincushion distortion of right and left rasters.

Color cathode ray tube apparatus

A deflection yoke includes ferrite core, horizontal deflection coil, vertical deflection coil, and insulating frame for insulating the horizontal and vertical deflection coils. The deflection yoke has a cross section that satisfies the following A to C. A: A plurality of magnetic substance convex portions projecting toward the tube axis are provided in the vicinity of a position of an inner surface of the ferrite core where a vertical axis crosses. B: Assuming that a minimum value among distances between the respective magnetic substance convex portions and a funnel is D, the distance between the ferrite core excluding the plurality of magnetic substance convex portions and the funnel is larger than the distance Dat any point of the ferrite core. C: A part of the vertical deflection coil is wound in a groove between the plurality of magnetic substance convex portions.

Color picture tube apparatus with particular deflection yoke structure

A ferrite core constituting a deflection yoke has a plurality of ridge-shaped convex portions on an inner circumferential surface. In a cross-section orthogonal to a center axis, the cross-sectional shape of an outer circumferential surface of the ferrite core is substantially circular, and the cross-sectional shape of an inner circumferential surface of the ferrite core excluding the convex portions is substantially circular in the vicinity of an end on a large diameter side of the ferrite core and is substantially rectangular in a portion between the vicinity of an end on a small diameter side and the vicinity of the end on the large diameter side. This can provide a low-cost color picture tube apparatus with a reduced deflection power and satisfactory productivity.

Ferrite core, deflection yoke, and color picture tube apparatus

A ferrite core constituting a deflection yoke includes a plurality of convex portions in a ridge shape on an inner surface thereof. Among the plurality of convex portions, assuming that the convex portions in a range excluding a range of &#x2212;20&#xb0; to +20&#xb0; with respect to a horizontal axis and a range of &#x2212;20&#xb0; to +20&#xb0; with respect to a vertical axis are diagonal convex portions, the lengths in a tube axis direction of at least horizontal axial convex portions on a horizontal axis or vertical axial convex portions on a vertical axis are larger than those of the diagonal convex portions. Because of this, a color picture tube apparatus with a deflection power reduced can be provided while the degree of freedom in a winding arrangement of deflection coils is secured.

Color picture tube apparatus

A color picture tube apparatus having a system for increasing an upper and lower pincushion distortion in the peripheral portion in the vertical direction by making the preliminary vertical deflection force when an electron beam is deflected toward the peripheral portion in the vertical direction of a phosphor screen relatively smaller than the preliminary vertical deflection force when an electron beam is deflected toward the middle portion in the vertical direction of the phosphor screen. With the color picture tube apparatus using an S-shaped distortion correction circuit, an upper and lower inner pincushion distortion can be optimized while correcting the upper and lower pincushion distortion.

Color picture tube apparatus with pincushion distortion correction

A color picture tube device that can adjust convergence without causing increases in cost and in power consumption is provided. One pair of magnetic flux generation means for generating a static quadrupole magnetic field are positioned above and below an area where a plurality of electron beams pass through. The static quadrupole magnetic field has an effect of adjusting convergence in a horizontal direction. In this construction, a magnetic flux generated by one of the two magnetic flux generation means that is closer to the plurality of electron beams is reduced, in sync with deflection of the plurality of electron beams in a vertical direction.

Color picture tube device having improved horizontal convergence

A color picture tube device has a funnel glass, a pair of horizontal deflection coils, an insulating frame, and a pair of vertical deflection coils. The pair of horizontal deflection coils are opposed to each other in a vertical direction around the outer surface of the funnel glass, and each have a window at the center. The insulating frame covers the horizontal deflection coils, resembles in shape a part of the funnel glass where the horizontal deflection coils are provided, and has openings in areas corresponding to windows of the horizontal deflection coils. The pair of vertical deflection coils are opposed to each other in a horizontal direction around the outer surface of the insulating frame, without overlapping the openings. A pair of correction coils are provided so as to be each at least partially inserted in a different one of the openings.

Color picture tube device with distortion correction coils

A color picture tube device that can suppress the deformation of the electron beam spot shape and improve the horizontal resolution using a simple construction is provided. A horizontal deflection coil generates a horizontal deflection magnetic field that is substantially uniform. A plurality of electron beams are substantially parallel with the tube axis when passing one end of a core of a deflection yoke facing an electron gun. A lens forming unit forms a lens through which the plurality of electron beams pass, between the electron gun end of the core and a phosphor screen. The lens has an effect of causing the plurality of electron beams to approach each other in a horizontal direction, irrespective of which part of the phosphor screen the plurality of electron beams reach.

Color picture tube device with improved horizontal resolution

The invention provides a deflection yoke comprising: a funnel-shaped core (ii) being made of a magnetic material, (iii) having, on its inner wall, ridges each of which starts from the narrower end and extends toward the wider end for a part of the length of the core, the ridges being arranged circumferentially at intervals and thereby forming core slots, and (iv) in which the remaining inner wall near the wider end is smooth; a first deflection coil wound as partially guided by the core slots; second deflection coil positioned more inward than the first deflection coil; and an insulating frame that (i) is sandwiched between the first and second deflection coils, and (ii) has, in an area corresponding to the core's smooth area, guiding slots extending along the CRT axis direction and being arranged circumferentially, wherein the second deflection coil is wound as partially guided by the guiding slots.

Deflection yoke and CRT device

A group of an upper coma correction coil and an upper four-pole coil is positioned in opposition to a group of a lower coma correction coil and a lower four-pole coil, with respect to an electron beam. A first circuit is composed of a circuit in which the lower four-pole coil and a first diode are connected in series is connected in parallel to the upper coma correction coil. A second circuit is composed of a circuit in which the upper four-pole coil and a second diode are connected in series is connected in parallel to the lower coma correction coil. The first circuit and the second circuit connected in series compose a YH correction circuit. The first diode and the second diode are positioned so as to have opposite polarities. Vertical deflection current is diverted to the YH correction circuit.

Color picture tube device in which YH misconvergence is corrected

Cathode ray tube having a deflection yoke with heat radiator

To realize an energy-efficient color cathode-ray tube, deflection power requirement is reduced for a deflection yoke that includes one or more bend-up-less saddle type coils in at least one of a horizontal deflection coil and a vertical deflection coil, without changing a basic setting. To do so, a protruding part is provided which protrudes towards an electron gun at an electron gun-side bend part of a horizontal deflection coil of a bend-up-less saddle shape. Each side of the protruding part, in a direction perpendicular to the tube axis, is located at a point so that a vertical line drawn from the point to a tube axis forms an angle &agr; of 10&deg; to 50&deg; inclusive with a vertical plane.

Deflection yoke with a low power consumption

A color cathode ray tube using a self-convergence method is provided with magnets for correcting top/bottom pincushion distortion, and includes a vertical deflection coil and a four-pole coil. The vertical deflection coil generates a first correction field distorted in a barrel shape. The four-pole coil is arranged on the side of a deflection yoke nearer to an electron gun, and corrects YH barrel pattern misconvergence by generating a second correction field. The strength of the second correction field varies according to the amount of vertical deflection applied to electron beams emitted by the electron gun.

Color cathode ray tube having a convergence correction apparatus

In a color display tube including an envelope including a front panel and a funnel, and an electron gun provided in a neck portion of the funnel, a horizontal outer diameter of the neck portion in a region on a rear end side is greater than a vertical outer diameter thereof in this region and a horizontal outer diameter thereof in a region on the front panel side, and a main lens of the electron gun is formed in the region on the rear end side. With this configuration, it is possible to achieve both an electric power saving and a high resolution in a display screen in a color display tube device, as well as to mount a deflection yoke in the color display tube easily.

Color display tube having a non-circular neck portion

In a color CRT apparatus in which three electron beams are not superimposed on one point on the screen at a time, a time difference is applied to modulating signals corresponding to the respective electron beams to adjust phase, thus achieving convergence of images, the screen is flat, both a horizontal magnetic deflection field and a vertical magnetic deflection field have uniform magnetic field distribution, paths of both side electron beams and a path of the center electron beam of the three electron beams emitted from electron sources are approximately parallel, and the time difference applied to the modulating signals is set to be approximately constant throughout the screen. Thus, images formed of imaging spots of the three electron beams can be superimposed on the screen with high precision to be matched without causing increased cost.

Growing community of inventors

Takatsuki, Japan

Etsuji Tagami