JPS5854777Y2 - In-line color cathode ray tube deflection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an in-line color cathode ray tube deflection device that emits red, green, and blue electron beams aligned in a horizontal line.

In this type of color cathode ray tube, the horizontal deflection coil is usually wound in a saddle shape, and the vertical deflection coil is wound in a toroidal shape. It is designed to create a magnetic field.

Figures 1 and 2 show this. Figure 1 shows the horizontal deflection coil and the resulting magnetic field, and Figure 2 shows the vertical deflection coil and the resulting magnetic field, both of which are along the tube axis 1. This is within the plane, and the left side of the figure is the screen side.

When an in-line color cathode ray tube is equipped with such a deflection device, as shown in FIG. 3, misconvergence occurs in which the arrival points of each beam become farther apart toward the left and right peripheries of the screen.

For this reason, conventionally, this misconvergence has been corrected using a horizontally periodic dispersion signal as shown in FIG.

In the case of a single electron gun, in which each beam is directed toward the center of a common main electron lens and diverged from this, and an electrostatic deflection plate for convergence is provided on the way to the divergence, this This convergence correction is performed by supplying a horizontally periodic variable voltage to the electrostatic deflection plate superimposed on the DC voltage.

The present invention prevents the above-mentioned misconvergence from occurring by devising the configuration of the deflection device itself without providing any special means for convergence correction.

In the conventional deflection device, as shown in FIG. 5, a horizontal deflection coil 2 wound in a saddle shape is attached to extend from the neck part of the tube to the funnel part, and a core 3 is wound in a toroidal shape on the outside of the horizontal deflection coil 2. A vertical deflection coil 4 is arranged,
The width of the vertical deflection coil 4 in the tube axis direction is equal to the beam emitting side bend portion 2a and the screen side bend portion 2b of the horizontal deflection coil 2.
The distance between them is approximately equal.

Therefore, as shown in Figure 6, the magnetic field distribution in the tube axis direction is such that the peak position PV of the vertical deflection magnetic field Hv is closer to the beam emission side than the peak position PH of the horizontal deflection magnetic field HH, and the horizontal deflection At the position PA inside the bend portion 2a on the beam emission side of the coil 2, the vertical deflection magnetic field Hv is larger than the horizontal deflection magnetic field HH, and at this position PA the deflection width in the vertical direction of the beam is larger than the deflection width in the horizontal direction. It's in a state where it's getting bigger.

On the other hand, in the deflection device according to the present invention, as shown in FIG. 13 is provided with a vertical deflection coil 14 wound in a toroidal shape, and the width of the vertical deflection coil 14 in the tube axis direction is the same as that of the horizontal deflection coil 12 at the beam emitting side bend portion 12a and the screen side bend portion 12a. This distance is made smaller than the distance between the horizontal deflection coils 12 and the bend portion 12b on the screen side of the horizontal deflection coil 12.
A sufficient gap 15 is formed between 2a and 2a, so that the magnetic field distribution in the tube axis direction is changed so that the peak position Pv of the vertical deflection magnetic field HV is the same as that of the horizontal deflection magnetic field H, as shown in FIG. Therefore, the vertical deflection magnetic field Hv should be moved closer to the peak position PIl side or even closer to the screen side than this.
As shown in FIG. 9, the electron beams are made to act closer to the screen where the distance between each electron beam becomes narrower, and at the inner position PA of the bend portion 12a on the beam emission side of the horizontal deflection coil 12. The horizontal deflection magnetic field HH is equal to or larger than the vertical deflection magnetic field Hv, and at this position PA, the beam deflection width in the horizontal direction is set to be equal to or larger than the deflection width in the vertical direction.

Furthermore, in this case, the horizontal deflection magnetic field HH caused by the horizontal deflection coil 12 has a stronger degree of bottle cushion than the conventional one, and the vertical deflection magnetic field HH caused by the vertical deflection coil 14 becomes stronger.
v is also made to have a stronger barrel than the conventional one.

In the conventional deflection device having the configuration shown in FIG. 5, when the horizontal deflection magnetic field is made to have a stronger bottle cushioning degree, that is, the horizontal deflection magnetic field is When the beams R, G and B scan the left half of the screen, the state shown by the broken line in FIG. 10 changes to the state shown by the solid line, and when the beams R, G and B scan the right half of the screen, the state shown by the broken line in FIG. 11 changes from the state shown by the solid line. When changed to the states shown in , the vertical component of the magnetic field for beams R and B on both sides decreases, and the horizontal component increases, so
As shown in FIG. 12, the horizontal misconvergence shown in FIG. 3 is corrected, but the vertical cross misconvergence occurs.

In this conventional device, when the vertical deflection magnetic field is made to have a stronger barrel degree, that is, the vertical deflection magnetic field is changed so that the beams R, G, and B are on the screen with the front side of the paper as the screen side in FIGS. 13 and 14. When scanning the upper half of the screen, the state shown by the broken line in Figure 13 can be changed to the state shown by the solid line, and when scanning the lower half of the screen, the state can be changed from the state shown by the broken line in Figure 14 to the state shown by the solid line. As for the magnetic field for the beams R and B on both sides, the horizontal component decreases and the vertical component increases, so as shown in Figure 15,
Although the vertical cross misconvergence shown in FIG. 12 is corrected, a different type of horizontal misconvergence than that shown in FIG. 3 occurs.

That is, in the conventional deflection device, when the horizontal deflection magnetic field is made to have a stronger bottle cushion effect and the vertical deflection magnetic field is made to have a stronger barrel effect, as shown in FIG.
A horizontal arcuate misconvergence occurs in which the arrival point of the red beam R shifts to the right and the blue beam B shifts to the left as you move up and down the screen.

In this way, in the deflection device according to the present invention, the horizontal deflection magnetic field is made to have a stronger bottle-cushion degree, the vertical deflection magnetic field is made to have a stronger barrel-like degree, and the seventh
As shown in the figure, the width of the vertical deflection coil 14 in the tube axis direction is made smaller than the distance between the bend portions 12a and 12b of the horizontal deflection coil 12, and this is moved toward the bent portion 12b side, so that the width is spaced between the bend portion 12a and the vertical deflection coil 14. A certain gap 15 is formed, and as shown in FIG. 9, the vertical deflection magnetic field acts closer to the screen where the distance between each electron beam is narrower as a whole, so that the vertical deflection magnetic field itself Even though the size remains the same, the deflection force acting on the beam decreases, and as a result, the vertical deflection magnetic field becomes more barrel-like as described above, causing the left and right beams R and The force that deflects B in opposite directions in the horizontal direction decreases as you move up and down the screen, and the magnetic field distribution in the tube axis direction of the vertical deflection magnetic field is appropriately shifted, resulting in the misconvergence shown in Figure 15. Correct convergence is achieved as shown in FIG.

According to experiments, the width of the vertical deflection coil 14 in the tube axis direction is about 55 to 70% of the distance between the bend parts 12a and 12b, and therefore the width of the gap 15 in the tube axis direction is about 55 to 70% of the distance between the bend parts 12a and 12b. If it is about 30 to 45% of the distance, the deflection width in the horizontal direction of the beam at the inner position PA of the bend portion 12 a becomes greater than the deflection width in the vertical direction as described above, and in this way, the deflection width of the beam in the vertical direction is It was found that misconvergence does not occur as shown in FIG. 4 if the deflection width in the horizontal direction of the beam at the inner position PA is greater than the deflection width in the vertical direction.

FIG. 16 shows the state of the deflection width of the beam, and in the conventional deflection device, at the inner position PA of the bend part 2a on the beam emission side of the horizontal deflection coil, and at the vicinity positions before and after the bend part 2a of the horizontal deflection coil,
As shown as a vertically elongated rectangle in the figure, the deflection width of the beam in the vertical direction is larger than the deflection width in the horizontal direction.

On the other hand, in the deflection device according to the present invention, at the inner position PA of the bend portion 12a on the beam emission side of the horizontal deflection coil, the deflection width in the horizontal direction of the beam is equal to the deflection width in the vertical direction, as shown by the arrow. or larger than this.

Of course, the aspect ratio of the screen is 3:4, which is the same as when using a conventional deflection device.

As in the deflection device according to the present invention, if the deflection width in the vertical direction of the beam is smaller than the deflection width in the horizontal direction at the inner position PA of the bend portion 12a on the beam emission side of the horizontal deflection coil 12, the influence of the bend portion may also be reduced. It becomes less.

That is, FIG. 17 shows the inner position P of the bend portion 2a on the beam emission side of the horizontal deflection coil 2 when using the conventional deflection device.
, A shows the state of the horizontal deflection magnetic field as seen from the screen side.The main magnetic field HHM in the vertical direction is generated by the current flowing in the part connecting the upper and lower bend parts 2a, and this causes the beam to be deflected in the horizontal direction. However, a magnetic field surrounding the bend portion 2a is generated by the current ① flowing through the bend portion 2a, and this becomes a magnetic field HHA −HHゎ which is directed toward the tube axis or radiates from the tube axis at the position PA.

These magnetic fields H5 (4 to HHD) cancel each other out and have almost no influence on the central beam G, but
As shown in the figure, large deflection widths in the vertical direction affect the beams R and B on both sides.

That is, these magnetic fields HHA-HHD are divided into a vertical component and a horizontal component, of which the vertical component is absorbed by the main magnetic field HHM, but the horizontal component is, as is clear from the figure, , forces are applied to beams R and B in opposite directions when scanning the upper half of the screen and when scanning the lower half of the screen, and in addition, forces are applied in opposite directions to each beam R and B. This acts to cause vertical cross-misconvergence as shown in FIG.

However, in the deflection device according to the present invention, since the deflection width in the vertical direction of the beam is small at the inner position PA of the bend portion 12a on the beam emission side, there is almost no influence from this horizontal magnetic field component, and this It rarely acts to cause misconvergence.

As described above, the deflection device according to the present invention has the extremely great advantage that a state without misconvergence can be obtained without performing convergence correction using disparate signals as in the conventional case.

[Brief explanation of drawings]

1 and 2 are diagrams showing the state of horizontal deflection magnetic field and vertical deflection magnetic field by a conventional deflection device, FIG. 3 is a diagram showing the state of misconvergence by a conventional deflection device, and FIG.
The figure shows the state in which misconvergence has been corrected.
Fig. 5 is a sectional view showing a conventional deflection device, Fig. 6 is a view showing the distribution state of the deflection magnetic field in the tube axis direction, Fig. 7 is a sectional view showing the deflection device according to the present invention, and Fig. 8 is a sectional view thereof. A diagram showing an example of the distribution state of the deflection magnetic field in the tube axis direction, No. 9
Figures 10 to 15 are diagrams showing that the position where the vertical deflection magnetic field acts is shifted by the deflection device according to the present invention.
The figure is a diagram for explaining that the deflection device according to the present invention eliminates misalignment and invergence, and FIG. 16 is a diagram showing the difference in beam deflection width between the conventional deflection device and the deflection device according to the present invention. FIG. 17 is a diagram for explaining the influence of the bend portion of the horizontal deflection coil in the case of a conventional deflection device. 12 is a horizontal deflection coil, 12a is a bend portion on the beam emission side, 12b is a bend portion on the screen side, 13 is a core, 14 is a vertical deflection coil, and 15 is a gap.

Claims (1)

[Scope of utility model registration request] The horizontal deflection coil is wound in a saddle shape, and the resulting horizontal deflection magnetic field is turned into a bottle cushion magnetic field, and the vertical deflection coil is wound in a toroidal shape, and the resulting vertical deflection magnetic field is turned into a barrel magnetic field. The length of the coil in the tube axis direction is selected to be 55 to 70% of the distance between the front and rear bend portions of the horizontal deflection coil, and the length between the bend portion of the horizontal deflection coil on the electron beam emission side and the vertical deflection coil is selected. Convergence is achieved by forming a sufficient gap so that the deflection width in the horizontal direction of the electron beam at the inner position of the bend portion on the electron beam emission side of the horizontal deflection coil is equal to or larger than the deflection width in the vertical direction. An in-line color cathode ray tube deflection device that compensates for