JP2716091B2 - In-line color picture tube device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an in-line type color picture tube device. (Prior Art) Generally, an in-line type color picture tube has a deflecting device, and this state is shown in FIG. The in-line type color picture tube 1 is configured as follows. That is, reference numeral 4 denotes a glass bulb. The glass bulb 4 is a panel 2, a funnel 3 joined to the panel 2, and a neck 5 joined to the funnel 3.
Is made up of And B (blue) on the inner surface of panel 2,
G (green) and R (red) light emitting phosphor screens are formed, and a shadow mask is provided to face the phosphor screens. Further, an in-line type electron gun 6 is sealed in the neck 5. In this case, the in-line type electron gun 6 moves in the horizontal direction (X
The shaft is enclosed inline. On the other hand, the deflecting device 7 includes a pair of saddle-type horizontal deflection coils 8 and a pair of saddle-type vertical deflection coils 10 wound in a toroidal shape around an outer core 9 thereof. It is mounted between the necks 5. The color picture tube 1 having the deflection device 7 is incorporated in a color picture tube device as shown in FIG. Many recent color picture tube devices, especially high-resolution color display devices, are compact, and a power supply unit and a video unit are often present near the deflection device 7. FIG. 4 shows a case where the power supply unit 11 is present near the deflection device 7. Power supply unit 11
Is covered with a metal cover 12 for the purpose of preventing unnecessary radiation and also functioning as a structural material of the device. As the metal cover 12, an iron plate or an aluminum plate is often used. In this case, an eddy current flows through the metal cover 12 due to the leakage magnetic field of the deflection device 7,
The magnetic field generated by the eddy current causes a problem that convergence is locally shifted on the screen. (Problems to be Solved by the Invention) As shown in FIGS. 5A and 5B, the toroidal vertical deflection coil 10 wound around the core 9 of the deflection device 7 has an effective deflection magnetic field due to its structure. Besides 13, there are many leakage magnetic fields 14. The leakage magnetic field 14 penetrates a part of the metal cover 12 that covers the power supply unit 11 located nearby. In normal cases, the vertical scanning frequency is as low as 40 to 100 Hz,
No eddy current flows through the metal cover 12. However, recent high-resolution color display devices tend to make the retrace time of vertical scanning extremely short, and the frequency during this period is 10
Corresponding to KHz and above. Therefore, an eddy current flows through the metal cover 12. 5 (a) and 5 (b), the metal cover 12 is present on the right side as viewed from the fluorescent screen side, and the arrangement of the electron guns is an arrangement of R, G, and B from the right side. If you are thinking. In this case, a demagnetizing field 16 is generated due to the eddy current 15. This demagnetizing field 16 affects the neck 5 of the deflection device 7 on the electron gun side, and acts in a direction to increase the deflection particularly for the right R beam. That is, as shown in FIG. 6, a misconvergence occurs such that the R beam is excessively deflected with respect to the B beam on the screen. This misconvergence is characterized in that it occurs locally only at the upper end of the screen affected by the retrace period.
This error is, for example, about 0.1 to 0.3 mm in a 14-inch 90 ° display tube, and occurs only within a range of about 5 mm from the upper end of the screen. Since the error is local, it is difficult to correct externally, and this is a serious problem in a high-resolution display tube that requires a convergence of 0.3 to 0.4 mm or less, and significantly deteriorates the convergence of the entire screen. The present invention has been made in view of the above problems, and has as its object to provide an in-line type color picture tube device in which local misconvergence is improved. [Constitution of the Invention] (Means for Solving the Problems) The present invention generates a panel, a funnel joined to the panel, and three electron beams joined to the funnel and arranged at the center and both outsides in-line. Consisting of a neck containing an electron gun to be mounted, an in-line type color picture tube having a deflection device mounted on the valve and comprising a pair of horizontal deflection coils and a vertical deflection coil, and a power supply unit arranged near the deflection device In the in-line type color picture tube device having the following, the widest surface of the metal plate on the side opposite to the position of the power supply unit of the picture tube and the core on the neck side of the picture tube in the tube axis direction from the core of the deflection coil does not exist. It is arranged so that it is located almost parallel to the tube axis over the region, and penetrates the leakage magnetic field in the direction perpendicular to the tube axis of the deflection device, resulting in a mismatch. An in-line type color cathode ray tube apparatus characterized by having a good conductivity metal plate nonmagnetic that generates a magnetic field that compensates for Jensu. (Operation) According to the present invention, during operation, the leakage magnetic field from the core side surface of the vertical deflection coil in the direction perpendicular to the tube axis penetrates the good conductive metal plate. Therefore, an eddy current flows through the metal plate, and a demagnetizing field is generated. This affects the electron beam near the neck of the color picture tube, and can correct local misconvergence caused by the metal cover of the display device. (Embodiment) Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In this embodiment, a metal cover that covers a power supply unit or a video unit of a display device is a fourth cover.
As shown in FIG. 5 and FIG. 5, the case where the electron beam exists on the right side when viewed from the phosphor screen side, the case where the screen is deflected to the upper side of the screen, and the case where the RGB electron gun array is arranged from the right side will be described. An in-line type color picture tube device according to the present invention is constructed as shown in FIG.
If the same parts as those in FIG. 1 are denoted by the same reference numerals, they have a pair of horizontal deflection coils 8 and a pair of vertical deflection coils 10. That is, a toroidal vertical deflection coil wound around the core 9
On the side of the electron gun 10, a good conductive metal plate 17 made of a non-magnetic material is provided on both sides of the core 9 and the neck side of the color picture tube on the side of the deflection device on the left side when viewed from the phosphor screen side. Has been established. In this case, the good conductive metal plate 17 is provided such that its widest surface faces the left side surface of the deflecting device and is substantially parallel to the tube axis. The good conductive metal plate 17 is made of, for example, an aluminum plate, and its size is
1.0mm, size is 50mm × 40mm. As described in the prior art, the metal cover 12
And the demagnetizing field 16 due to the stray magnetic field 14 causes misconvergence at the upper end of the screen as if the R beam and B beam were deflected unnecessarily. Can be corrected. As described above, when the good conductive metal plate 17 is added, the leakage magnetic field of the toroidal vertical deflection coil 10 shown in FIG.
14 penetrates the good conductive metal plate 17 and causes a magnetic field 20 due to an eddy current 19 in a direction to hinder the eddy current from leaking to the neck side. As a result, the R beam and the B beam as shown in FIG.
This makes it possible to correct the beam displacement on the screen so as to match the displacement. Also, the good conductive metal plate 17 has a core 9 portion,
It is desirable that both sides of the neck 9 have no core 9. For example, when the good conductive metal plate 17 exists only facing the core 9, the leakage magnetic field 14 penetrates the good conductive metal plate 17, The demagnetizing field 20 is cut off by the core 9, the influence on the beam is reduced, and the correction effect is slightly reduced. Conversely, when the good conductive metal plate 17 is added so as to be located only on the neck side, the amount of the good conductive metal plate 17 receiving the leakage magnetic field 14 is reduced, so that the correction effect is still slightly reduced. However, the correction amount can be freely controlled by the size of the good conductive metal plate 17 and the distance from the deflection device. In this embodiment, the misconvergence as shown in FIG.
What happened could be reduced to almost zero. (Modification) The good conductive metal plate 17 may not be an aluminum plate.
Any non-magnetic metal sheet may be used. For example,
It is a stainless steel plate or the like. However, in the case of a thin metal plate made of a magnetic material, the object of the present invention cannot be achieved because the effective deflection magnetic field is greatly affected and the convergence of the entire screen is changed. On the other hand, if the thickness of the non-magnetic metal sheet is too small, the eddy current hardly flows and the effect is small. Generally, a thickness of 0.3 to 0.5 mm or more is required. Further, in the above embodiment, the metal cover 12 covering the power supply unit or the video unit of the display device is used.
However, although the case where the metal cover 12 exists on the right side when viewed from the fluorescent screen side has been described, it goes without saying that the metal plate 17 of the present invention is provided on the right side when the metal cover 12 is present on the left side. In the above embodiment, the deflection device having a toroidal vertical deflection coil having a particularly large leakage magnetic field has been described. However, the present invention can be applied to a deflection device having a saddle type vertical deflection coil. [Effects of the Invention] According to the present invention, a good conductive metal plate made of a non-magnetic material is opposed to a side opposite to a power supply unit of a picture tube, and the widest surface of the metal plate becomes substantially parallel to the tube axis. Thus, local convergence caused by the metal cover of the display device, particularly, misconvergence occurring at the beginning of vertical scanning can be effectively corrected.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a deflecting device used in an in-line type color picture tube device according to an embodiment of the present invention, and FIG. 2 is a relation between the deflecting device and a metal cover of a display device. FIG. 3 is a cross-sectional view as viewed from the phosphor screen side, FIG. 3 is a plan view showing an in-line type color picture tube equipped with a conventional deflection device, and FIG. 4 is a display device using the in-line type color picture tube of FIG. 5 (a) and 5 (b) are perspective views and explanatory views showing the relationship between a conventional deflection device and a metal cover of a display device, and FIG. 6 is an upper end of a screen. FIG. 4 is a plan view showing misconvergence in FIG. 8 ... horizontal deflection coil, 9 ... core, 10 ... vertical deflection coil, 17 ... good conductive metal plate.

Claims (1)

(57) [Claims] A bulb comprising a panel, a funnel joined to the panel, and a neck containing an electron gun for generating three electron beams which are arranged in-line at the center and both outsides joined to the funnel, and a pair of valves mounted on the bulb. An in-line color picture tube having a deflection device comprising a horizontal deflection coil and a vertical deflection coil, and a power supply unit arranged near the deflection device, wherein the power supply unit of the picture tube is On the side opposite to the position, and the widest surface of the metal plate is arranged so as to be located substantially parallel to the tube axis from the core of the deflection coil to the region where the core on the neck side of the picture tube in the tube axis direction does not exist, Non-magnetic that generates a magnetic field that compensates for misconvergence by penetrating the leakage magnetic field in the direction perpendicular to the tube axis of the deflection device Line type color cathode ray tube apparatus characterized by having a good conductivity metal plate.