JPH08102265A - Color picture tube device - Google Patents

Abstract

PURPOSE: To provide a color picture the having high resolution, an excellent withstand voltage with characteristic and high reliability by correcting astigmatism of a deflection magnetic field with a multi-pole lens formed of grids, which are respectively connected through a resistor so as to generate a potential difference. CONSTITUTION: Electron beam emitted from an electron beam generating unit GE of an electron gun 21 is focused by a main lens unit ML, which is formed of plural grids C3 -C7 , and a deflection yoke is scanned for deflection on a target. In this color picture tube, positive high voltage is applied to a seventh grid G7 of the main electron lens unit ML. Dynamic voltage is applied to a sixth grid G6 , and the grid G6 is connected to the adjacent fifth grid G5 through a resistor 22 so as to generate a potential difference, and a multi-pole lens QL for correcting deflection aberration is thereby formed. Furthermore, electrostatic capacity Ca, Cb between the grids G5 , G6 and G5 , G4 , and resistance value R of the resistor 22, frequency of dynamic voltage fH are set so as to satisfy π<2> .fH.Ca.R>=13 (1-γ), on condition that γ=Ca/(Ca+Cb).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color picture tube apparatus, and more particularly to a dynamic focus type color picture tube apparatus for correcting deflection aberration caused by a magnetic field generated by a deflection yoke.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 9, a color picture tube device has an envelope composed of a panel 1 and a funnel 2 integrally joined to the panel 1, and the inner surface of the panel 1 has an envelope. A phosphor screen 3 (target) is formed of a stripe-shaped or dot-shaped three-color phosphor layer that emits blue, green, and red, and a large number of apertures are formed inside the phosphor screen 3 so as to face the phosphor screen 3. The shadow mask 4 is attached. On the other hand, in the neck 5 of the funnel 2, an electron gun 7 that emits three electron beams 6B, 6G and 6R is arranged. A deflection yoke 8 is attached to the outside of the funnel 2. Then, the three electron beams 6B, 6G and 6R emitted from the electron gun 7 are deflected by the horizontal and vertical deflection magnetic fields generated by the deflection yoke 8, and the phosphor screen 3 is horizontally and vertically scanned through the shadow mask 4. As a result, a structure for displaying a color image is formed.

In such a color picture tube device, in particular, the electron gun 7 is arranged in a single row consisting of a center beam 6G passing through the same horizontal plane and a pair of side beams 6B and 6R.
An in-line type electron gun that emits electron beams 6B, 6G and 6R is used. On the other hand, the horizontal deflection magnetic field generated by the deflection yoke 8 is a pincushion type and the vertical deflection magnetic field is a barrel type.
A self-convergence type in-line type color picture tube device for self-focusing the three electron beams 6B, 6G and 6R arranged in a row has been widely put into practical use.

Usually, the electron gun 7 controls the electron emission from the cathode and focuses the emitted electrons to form three electron beams 6B, 6G and 6R, and a plurality of electrodes which are sequentially adjacent to the cathode. And a main electron lens unit composed of a plurality of electrodes for focusing the three electron beams 6B, 6G, 6R obtained from the electron beam generator on the phosphor screen 3.

In such a color picture tube device, in order to improve the image characteristics on the phosphor screen 3,
Three electron beams 6B, 6G, 6R emitted from the electron gun 7
Must be properly focused. However, like the self-convergence in-line type color picture tube device, the horizontal deflection magnetic field for deflecting the three electron beams 6B, 6G, 6R emitted from the electron gun 7 is pincushion type, and the vertical deflection magnetic field is barrel type. If a uniform magnetic field is applied, the electron beams 6B, 6G, and 6R will undergo astigmatism. For example, the pincushion type horizontal deflection magnetic field will be described. As shown in FIG.
B, 6G, 6R) is a pincushion type horizontal deflection magnetic field 1
The force in the direction of arrows 11H and 11V is received by 0, and (b)
As shown in, the beam spot 12 of the electron beam on the peripheral portion of the phosphor screen is significantly distorted due to the deflection aberration.
The deflection aberration received by the electron beam occurs because the electron beam is in a vertically overfocused state, and a large halo 13 (bleeding) occurs in the vertical direction. The deflection aberration received by the electron beam becomes larger as the tube becomes larger and the deflection angle becomes wider, and the resolution around the phosphor screen is significantly deteriorated.

Japanese Unexamined Patent Publication No. 61-99249 (USP
No. 4,814,670) discloses an electron gun that solves the deterioration of resolution due to the deflection aberration. The electron guns disclosed in these publications are basically shown in FIG.
It is formed in the structure shown in FIG. That is, each has first to fifth grids G1 to G5, and forms the electron beam generator GE, the quadrupole lens QL, and the final focusing lens EL along the traveling direction of the electron beam. The quadrupole lens QL of each electron gun has three non-circular electron beam passage holes 14a and 14b shown in (b) and (c) on the respective facing surfaces of the third and fourth grids G3 and G4.
, 14c, 15a, 15b, 15c.

The correction of the deflection aberration by the electron gun is equivalently shown by an optical lens as shown in FIG. That is, the electron gun is a dynamic focus type electron gun that sequentially forms the quadrupole lens QL and the final focusing lens EL from the cathode K in the phosphor screen direction, and the electron beam 6 from the cathode K is directed to the phosphor screen 3. In the non-deflected landing in the center, the third grid and the fourth grid
The potentials of the grids are made almost the same, the quadrupole lens QL is hardly acted, and the electron beam 6
Are finally focused on the center of the phosphor screen 3 by the final focusing lens EL. On the other hand, at the time of deflection, the potential of the fourth grid is increased to form the quadrupole lens QL as shown by the broken line, and the divergence in the vertical direction and the focusing in the horizontal direction are performed, and at the same time, the vertical direction of the final focusing lens EL , Weakens the focusing action in both horizontal directions. As a result, the electron beam 6 is insufficiently focused in the vertical direction, but is properly focused by the focusing action due to the deflection aberration (astigmatism). On the other hand, in the horizontal direction, the focusing action of the quadrupole lens QL and the final focusing lens E
Due to the reduction of the focusing action of L, the total focusing in the horizontal direction hardly changes, and due to the magnetic field generated by the deflection yoke 8, the focusing becomes slightly insufficient. However, since the peripheral portion of the phosphor screen 3 which the electron beam 6 reaches is farther from the electron gun than the central portion, it is also properly focused in the horizontal direction.

[0008]

As described above, the color picture tube device which deflects the three electron beams arranged in a row emitted from the electron gun by the non-uniform magnetic field generated by the deflection yoke is not affected by the non-uniform magnetic field. The beam spot around the phosphor screen is distorted due to the point aberration. The deflection aberration received by the electron beam becomes larger as the tube becomes larger and the deflection angle becomes wider, and the resolution in the peripheral portion of the phosphor screen is significantly deteriorated. As an electron gun that solves this deterioration in resolution, a dynamic focus system in which electrodes are formed by first to fifth grids and an electron beam generator, a quadrupole lens, and a final focusing lens are sequentially formed in the phosphor screen direction from the cathode An electron gun has been proposed.

However, in such a dynamic focus type electron gun, since two kinds of medium voltages of about 5 to 10 kV have to be supplied to the third grid and the fourth grid from the outside of the tube, the voltage supply unit. Withstand voltage is a problem. In addition, the connection line for applying a predetermined voltage to each electrode becomes long, the withstand voltage inside the tube decreases, and the focusing characteristics of the electron beam due to discharge and leakage current deteriorate. There is a problem of impairing sex.

In view of this, in Japanese Unexamined Patent Publication No. 1-232643 (USP 4,945,284), two adjacent grids of a plurality of grids are connected by resistors arranged in a tube, and the final accelerating electrode of the two grids is connected. There is shown an electron gun in which a medium voltage supplied from the outside of the tube is set to one type by applying a dynamic voltage to one side close to, and applying the dynamic voltage to the other side via the resistor.

However, the resistance value of the resistor is 20.
It is shown to be about 0 kΩ, and sufficient consideration has not been given to the setting of this resistance value. That is, disclosed 2
When the resistance value is about 00 kΩ, even if a dynamic focus voltage is applied, a potential difference does not occur between two electrodes connected by a resistor, and a multipole lens that corrects the astigmatism of the deflection magnetic field is not formed. Therefore, it is difficult to correct astigmatism.

The present invention has been made in view of the above problems, and has an effect of a multipole lens for correcting an astigmatism of a deflection magnetic field by generating a potential difference between two electrodes connected by a resistor. The present invention aims to form a color picture tube device having a high resolution over the entire screen and having a high withstand voltage characteristic of the electron gun and having a high reliability, by correcting the astigmatism.

[0013]

SUMMARY OF THE INVENTION The present invention is an electron gun having a main electron lens portion formed of a plurality of grids for focusing at least one electron beam emitted from an electron beam generating portion on a target, and At least a deflection yoke that generates a magnetic field for deflecting and scanning an electron beam emitted from an electron gun on a target, the electron gun includes at least one cathode and a plurality of grids, and at least two adjacent grids among the plurality of grids. Are connected to each other by a resistor arranged in the tube, a non-circular electron beam passage hole is formed in the facing surface of the adjacent grid, and at least one of the adjacent grids has a dynamic change that is synchronized with the deflection of the electron beam. The present invention relates to a color picture tube device equipped with an electron gun for applying a voltage.

According to the present invention, the plurality of grids of the electron gun are at least first to fourth grids arranged in the target direction from the cathode side, and the first to third grids are adjacent to each other, and the fourth grid is adjacent to the fourth grid. A high voltage of the anode is applied to the grid, and a dynamic voltage in which a voltage that changes in synchronization with the deflection of the electron beam is superimposed on a DC voltage lower than the high voltage of the anode is applied to the third grid. The grid and the third grid are at least connected via a resistor arranged in the tube, and a voltage lower than the voltage of the second grid is applied to the first grid, and the grid of the second and third grids is applied. A multipole lens forming means for correcting a deflection aberration is provided between them, and a capacitance Ca between the third grid and the second grid and a capacitance between the second grid and the first grid are provided. Cb, Anti vessels of resistance R, the frequency fH of the dynamic voltage synchronized with the horizontal ^{deflection, π 2 · fH · Ca ·} R ≧ 13 · When the circular constant π (1-γ), however, γ = Ca / ( It has a relationship of Ca + Cb).

According to the present invention, the plurality of grids of the electron gun are at least first to seventh grids arranged in the target direction from the cathode, the first to sixth grids are adjacent to each other, and the seventh grid is An anode high voltage is applied, and a dynamic voltage in which a DC voltage lower than the anode high voltage and a voltage that changes in synchronization with the deflection of the electron beam are applied is applied to the sixth grid, and the fifth grid is the sixth grid. At least they are connected via a resistor arranged in the tube, and a multipole lens forming means for correcting the deflection aberration is provided between the fifth and sixth grids, and the fourth grid is connected to the voltage of the sixth grid. Lower voltage is applied, the fourth grid and the second grid are connected in the tube, the first grid is applied with a lower voltage than the fourth grid, and the sixth grid and the fifth grid are applied. And a capacitance Ca between the fifth grid and the fourth grid, a resistance value R of the resistor, a frequency fH of a dynamic voltage synchronized with horizontal deflection, and a pi of π. When π ² · fH · Ca · R ≧ 13 · (1-γ) However, γ = Ca / (Ca + Cb).

Further, according to the present invention, the plurality of grids of the electron gun are at least first to fourth grids arranged in the target direction from the cathode, the first to third grids are adjacent to each other, and the second and third grids are adjacent to each other. The third grid is connected by the first resistor, the third and fourth grids are connected by the second resistor connected to the first resistor, and a predetermined voltage is applied to the first grid. Then, an anode high voltage is applied to the fourth grid, a voltage supply means is connected to the third grid outside the tube, and a dynamic voltage that changes in synchronization with the deflection of the electron beam is applied. A multipole lens forming means for correcting deflection aberration is provided between the third grids, and electrostatic capacitance Ca between the third grid and the second grid and between the second grid and the first grid are provided. Capacitance Cb of the Resistor of resistance value R, and the frequency fH of the dynamic voltage synchronized with the horizontal deflection, the circular constant π
Where π ² · fH · Ca · R ≧ 13 · (1-γ) However, there is a relation of γ = Ca / (Ca + Cb).

Further, according to the present invention, the plurality of grids of the electron gun are at least first to fifth grids arranged in the target direction from the cathode, the first to third grids are adjacent to each other, and the second, The third grid is connected by the first resistor, the third and fourth grids are connected by the second resistor, and the fourth and fifth grids are connected by the third resistor. Dynamic voltage which is applied to the third grid, an anode high voltage is applied to the fifth grid, a voltage supply means is connected to the third grid outside the tube, and which changes in synchronization with the deflection of the electron beam. Is provided, and a multipole lens forming means for correcting the deflection aberration is provided between the second and third grids, and the electrostatic capacitance Ca between the third grid and the second grid and the second grid are With the first grid Capacitance Cb between the resistance value of the first resistor R, and a frequency fH of the dynamic voltage synchronized with the horizontal ^{deflection, π 2 · fH · Ca ·} R ≧ 13 · (1 when the circular constant [pi -Γ) However, there is a relation of γ = Ca / (Ca + Cb).

[0018]

With the above configuration, for example, in the case of the inventions of claims 1 and 2 (the same applies to the inventions of claims 3 and 4),
During the period in which the electron beam is horizontally deflected, the relationship of 2π · fH · Ca · R >> 1 is satisfied, and the capacitance Ca between the second grid and the third grid and the first grid and the second grid are satisfied. It is possible to divide and reduce the dynamic voltage through the electrostatic capacitance Cb between the grids and apply the AC voltage to the second grid in an alternating manner. As a result, the potential difference between the second grid and the third grid increases with horizontal deflection of the electron beam, and the multipole lens formed by the second and third grids strengthens with horizontal deflection of the electron beam. At the same time, the focusing action of the final focusing lens is weakened. Therefore, it is possible to correct the astigmatism of the horizontal deflection magnetic field.

As a result, it becomes possible to correct the astigmatism of the deflection magnetic field only by supplying one medium voltage from the outside of the tube to the electron gun, and the resolution is high over the entire screen and the withstand voltage is excellent. It is possible to provide a high-performance color picture tube device having characteristics and being highly reliable. In addition to this, in the case of the present invention as defined in claims 3 and 4, the circuit cost of the color picture tube device can be significantly reduced by supplying the intermediate voltage via a resistor provided outside the tube. it can.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the drawings. FIG. 3 shows a color picture tube device as one embodiment of the invention. This color picture tube device has an envelope composed of a panel 1 and a funnel 2 integrally joined to the panel 1, and an inner surface of the panel 1 has three stripe-shaped colors that emit light of blue, green and red. A phosphor screen 3 (target) composed of a phosphor layer is formed, and a shadow mask 4 having a large number of apertures formed therein is mounted facing the phosphor screen 3 and inside thereof. On the other hand, in the neck 5 of the funnel 2, an electron gun 21 for emitting the three electron beams 20B, 20G, 20R arranged in a line passing through the same horizontal plane is arranged. A deflection yoke 8 is attached to the outside of the funnel 2. Then, the electron gun 21
The three electron beams 20B, 20G, 20R emitted from the deflector are deflected by the horizontal and vertical deflection magnetic fields generated by the deflection yoke 8, and the phosphor screen 3 is horizontally and vertically scanned through the shadow mask 4 to form a color image. It is formed in a display structure.

As shown in FIG. 1 (corresponding to claims 1 and 2), the electron gun 21 includes three cathodes K arranged in a line in the horizontal direction (H-axis direction), and these cathodes K are heated separately. The heater H has first to seventh grids G1 to G7 arranged in the phosphor screen direction at a predetermined distance from the cathode. The fifth grid G5 (second
Grid) and the sixth grid G6 (third grid) are electrically connected via a resistor 22 arranged in the tube.

The first and second grids G1 and G2 are
It is composed of a plate-shaped electrode, and on the plate surface, corresponding to the three cathodes K, three relatively small substantially circular electron beam passage holes are provided in a line arrangement.

Each of the third to sixth grids G3 to G6 is formed of a tubular electrode, and the surface of the third grid G3 facing the second grid G2 faces the second grid corresponding to the three cathodes K. 3 larger than the electron beam passage hole of G2
A plurality of substantially circular electron beam passage holes are arranged in a line. Also, the fourth grid G of this third grid G3
4 (first grid) facing surface, fourth grid G4 and fifth grid G5 facing fourth grid G4, and sixth grid G6 seventh grid G7 (fourth grid)
In the surface facing each other, there are three substantially circular electron beam passage holes corresponding to the three cathodes K, which are larger than the electron beam passage holes in the surface facing the second grid G2 of the third grid G3. They are arranged in a line. Further, on the surface of the fifth grid G5 facing the sixth grid G6, as shown in FIG.
As shown in (a), three vertically elongated electron beam passage holes 24a, 24b, 24c corresponding to the three cathodes and having a major axis in the vertical direction (V-axis direction) are provided in a row. ing. On the other hand, on the surface of the sixth grid G6 facing the fifth grid G5, as shown in (b), three substantially horizontally long electrodes having the major axis in the horizontal direction corresponding to the three cathodes K are provided. The electron beam passage holes 25a, 25b and 25c are provided in a line. The seventh grid G7 is composed of a cup-shaped electrode, and the surface of the sixth grid G6 facing the sixth grid G6 passes through the electron beam of the surface of the sixth grid G6 facing the seventh grid G7 corresponding to the three cathodes. Three substantially circular electron beam passage holes of the same size as the holes are arranged in a line.

In this electron gun 21, the cathode K and the first
The third grids G1 to G3 form an electron beam generator GE that controls electron emission from the cathode K and accelerates and concentrates the emitted electrons to form an electron beam.
Main electron lens unit ML for focusing the electron beam on the phosphor screen by the third to seventh grids G3 to G7.
Is formed. In the main electron lens portion ML, a fifth grid G5 in which substantially vertically long electron beam passage holes 24a, 24b and 24c are formed and substantially horizontally long electron beam passage holes 25a, 25b and 25c are formed. A multipole lens QL is formed between the sixth grid G6 and the final focusing lens EL between the sixth grid G6 and the seventh grid G7.
Is formed.

In such an electron gun 21, the seventh grid G7 has an anode terminal 27 provided on the funnel.
25-35 kV from the high voltage power supply 28 (see FIG. 3)
Anode high voltage Eb is applied. Also the 6th grid G6
And the third grid G3 are connected in a pipe, these third,
The 6 grids G3 and G6 have anode positive voltage Eb of 20 to 3 supplied from the electron gun power source 31 through a stem pin 30 (see FIG. 3) that hermetically penetrates the stem 29 at the neck end.
A voltage of about 5% is used as a reference voltage Vf (DC voltage), and a dynamic focus voltage in which a parabolic voltage Vd that changes in synchronization with the deflection of the electron beam is superimposed is applied to this reference voltage Vf. A voltage to be described later is applied to the fifth grid G5 connected to the sixth grid G6 via the resistor 22. Further, the second grid G2 and the fourth grid G4 are connected in a pipe, and the second and fourth grids G2 and G4 are connected to the electron gun power source 31 to 500 to 1000 V through a stem pin 29 that hermetically penetrates the stem 28.
Of the electron gun power source 31 to 100-2.
A voltage obtained by superimposing a video signal on a DC voltage of 00V is supplied.

With respect to the voltage applied to the fifth grid G5, at least a DC voltage component of the dynamic focus voltage applied to the sixth grid G6 is supplied via the resistor 22 to the fifth grid G5 and the fifth grid G5. The capacitance Ca between the surfaces facing the 6th grid G6 is electrostatically coupled to the 6th grid G6, and a voltage on which the AC component of the dynamic focus voltage induced by the capacitance Ca is superimposed is applied. To be done.

The AC component ed of the voltage applied to the fifth grid G5 has a resistance value R of the resistor 22 and a fifth grid G5 and a fourth grid G5, as shown in the electrical equivalent circuit of FIG.
Cb is the capacitance between the surfaces facing the grid G4 and V is the dynamic focus voltage applied to the sixth grid G6.
d, its frequency is f, the phase difference is φ, the circular constant is π, and ω = 2πf j ² = −1.

[0028]

[Equation 1]

However, τ = R · Ca γ = Ca / (Ca + Cb) The phase difference φ is expressed by the equation 2.

[0030]

[Equation 2]

The sizes of the capacitances Ca and Cb are determined by the distance between the facing grids G4, G5 and G6 and the facing area, respectively. Each of these grids G4, G
If the facing areas of 5 and G6 are substantially the same, the fifth grid G
5 and 6th grid G6 adjustment is ga, 4th grid G4
By setting the adjustment of the fifth grid G5 to gb, γ = gb / (ga + gb) can be expressed.

In the above equation, ω · Ca · R, that is, 2π · f
Since the value of Ca · R changes at the frequency f of the dynamic focus voltage, the capacitance Ca and the resistance value R are appropriately selected and the horizontal deflection frequency fH is used to determine the fifth grid G5.
The voltage ed induced in the voltage can be set appropriately.
That is, it is possible to correct the astigmatism of the deflection magnetic field by generating a potential difference between the fifth grid G5 and the sixth grid G6 and forming a multipole lens between the fifth and sixth grids G5 and G6. is there.

That is, when 2π · fH · Ca · R >> 1, about γ (= Ca / (Ca + Cb)) times the AC component Vd of the dynamic focus voltage applied to the fifth grid G5 and the sixth grid G6. Can be superimposed. For example, when Ca = Cb, as shown in FIG.
50% (50% Vd) of the parabolic voltage Vd which changes in synchronization with the deflection of the electron beam can be superposed on the electrodes of the fifth grid G5, and the voltage of the fifth grid G5 is shown by the curve 33. And the sixth grid G indicated by the curve 34
The potential difference between the fifth grid G5 and the sixth grid G6 can be increased in accordance with the deflection of the electron beam by changing the voltage in synchronization with the dynamic focus voltage applied to the sixth grid G5.

Therefore, the resistance value R, the capacitance between the electrodes, and the frequency f of the dynamic voltage are selected as described above, and the opposing beam passage holes of the fifth and sixth grids G5 and G6 are respectively shown in FIG. By configuring as shown in a) and (b), the action of converging the multipole lens formed between the fifth and sixth grids G5 and G6 in the horizontal direction and diverging in the vertical direction is deflected by the electron beam. Accordingly, the focusing action of the final focusing lens EL can be weakened at the same time, and astigmatism of the horizontal deflection magnetic field can be corrected. Note that TH is one cycle of horizontal deflection.

Here, in an actual color picture tube, a range that is 4% to 8% wider in the horizontal direction than the image output range of the screen is overscanned, so a phase difference of about 4π / 104 rad is allowed. Therefore, considering this, π ² · fH · Ca · R ≧ 13 · (1-γ), and the condition of R ≧ 13 · (1-γ) / (π ² · fH · Ca) should be satisfied. become.

Since the capacitance between the electrodes is about 2 pF, Ca = Cb = 2 pF and the horizontal deflection frequency fH.
Is set to 15.75 kHZ, R ≧ 20.9 MΩ, and by setting the resistance value R of the resistor 22 connecting the fifth grid G5 and the sixth grid G6 to 20.9 MΩ or more, a practical high rank is obtained. It is possible to induce about 50% of the dynamic focus voltage applied to the sixth grid G6 to the fifth grid G5 without the problem of phase difference.

Although Ca = Cb is set in the above embodiment, the present invention is not limited to this, and can be applied to the case where Ca and Cb are adjusted within a practical range and the ratio of the superimposed voltage is set.

Next, another embodiment of the present invention will be described. In this embodiment, as shown in FIG. 6 (corresponding to claim 3), the electron gun 21 has three cathodes K arranged in a line in the horizontal direction (H-axis direction), and heaters for heating the cathodes K respectively. H, first to third electrodes arranged in the direction of the phosphor screen in the order of a predetermined distance from the cathode.
Grids G1 to G3, fourth grid G4 (first grid), fifth grid G5 (second grid), sixth grid G6 (third grid), seventh grid G7 (fourth grid)
Grid). The fifth grid G5 and the sixth grid G6 are electrically connected to each other via a first resistor 221 arranged inside the tube, close to the electron gun. The sixth grid G6 and the seventh grid G7 are electrically connected to each other through a second resistor 222 which is disposed in the tube close to the electron gun and is connected in series to the first resistor 221. ing. Further, the sixth grid G6 is connected to one end of a variable resistor 50 arranged outside the tube via a stem pin 20 that hermetically penetrates the stem 29 (see FIG. 3) at the neck end. The other end of the variable resistor 50 is grounded.

The first and second grids G1 and G2 are
It is composed of a plate-shaped electrode, and on the plate surface, corresponding to the three cathodes K, three relatively small substantially circular electron beam passage holes are provided in a line arrangement.

Each of the third to seventh grids G3 to G7 is composed of a cylindrical electrode, and the surface of the third grid G3 facing the second grid G2 faces the second grid corresponding to the three cathodes K. 3 larger than the electron beam passage hole of G2
A plurality of substantially circular electron beam passage holes are arranged in a line. Also, this third grid G3, the fourth grid G4
The third grid G3 and the second grid G2 facing the second grid G2 are provided with three substantially circular shapes which are larger than the electron beam passing holes corresponding to the three cathodes K, respectively. The electron beam passage holes are arranged in a line. The fifth grid G5 faces the fourth grid G4, the sixth grid G6 faces the seventh grid G7, and the seventh grid G7 corresponds to the four cathodes G4, respectively. The three substantially circular electron beam passage holes, which are larger than the electron beam passage holes in FIG. Further, on the surface of the fifth grid G5 facing the sixth grid G6, as shown in FIG. 2 (a), the vertical direction (V-axis direction) corresponding to the three cathodes is provided.
Of three vertically long electron beam passage holes 2 each having a long diameter
4a, 24b and 24c are arranged in a line. On the other hand, on the surface of the sixth grid G6 facing the fifth grid G5, as shown in (b), three substantially horizontally long electrodes having the major axis in the horizontal direction corresponding to the three cathodes K are provided. The electron beam passage holes 25a, 25b and 25c are provided in a line.

In this electron gun 21, the cathode K and the first
The third grids G1 to G3 form an electron beam generator GE that controls electron emission from the cathode K and accelerates and concentrates the emitted electrons to form an electron beam.
Main electron lens unit ML for focusing the electron beam on the phosphor screen by the third to seventh grids G3 to G7.
Is formed. In the main electron lens portion ML, a fifth grid G5 in which substantially vertically long electron beam passage holes 24a, 24b and 24c are formed and substantially horizontally long electron beam passage holes 25a, 25b and 25c are formed. A multipole lens QL is formed between the sixth grid G6 and the final focusing lens EL between the sixth grid G6 and the seventh grid G7.
Is formed.

In the electron gun 21 as described above, the seventh grid G7 has an anode terminal 27 provided on the funnel.
25-35 kV from the high voltage power supply 28 (see FIG. 3)
Anode high voltage Eb is applied. Also the 6th grid G6
And the third grid G3 are connected in a pipe, these third,
The sixth grid G3, G6 has a second resistor 222 connected to the sixth grid G6 and the seventh grid G7 and an anode high voltage supplied to the seventh grid G7 by a variable resistor 50 arranged outside the tube. Eb is resistance-divided and anode high voltage E
A voltage of about 20 to 35% of b is supplied as a reference voltage Vf (DC voltage), and a parabolic voltage Vd that changes in synchronization with the deflection of the electron beam is superposed on the reference voltage Vf from the electron gun power source 31. A dynamic focus voltage is applied. The first resistor 22 is connected to the sixth grid G6.
A voltage to be described later is applied to the fifth grid G5 connected through 1. Further, the fourth grid G4 and the second grid G4 are connected in a tube, and the second and fourth grids G2 and G4 are connected to the electron gun power source 31 through the stem pin 30 that hermetically penetrates the stem 29 to 500 to 1000 V.
The cutoff voltage of is supplied. The first grid G1 is grounded, and the cathode K has 100 to 100
A voltage obtained by superimposing a video signal on a DC voltage of 200V is supplied.

Regarding the voltage applied to the fifth grid G5, the sixth grid G5 is supplied through the first resistor 221.
At least a direct-current voltage component of the dynamic focus voltage applied to 6 is supplied, and is electrostatically coupled to the sixth grid G6 by the capacitance Ca between the facing surfaces of the fifth grid G5 and the sixth grid G6. , This capacitance Ca
A voltage in which the AC component of the dynamic focus voltage induced via the voltage is superimposed is applied.

The AC component ed of the voltage applied to the fifth grid G5 has a resistance value R of the first resistor 221 and a fifth grid G, as shown in the electrical equivalent circuit of FIG.
The capacitance between the opposing surfaces of 5 and the fourth grid G4 is Cb,
The dynamic focus voltage applied to the sixth grid G6 is Vd, its frequency is f, phase difference is φ, and pi is π.
And ω = 2πf j ² = −1, it is expressed by Expression 1, and the phase difference φ is expressed by Expression ² .

The sizes of the capacitances Ca and Cb are determined by the distance between the facing grids G4, G5 and G6 and the facing area, respectively. Each of these grids G4, G
If the facing areas of 5 and G6 are substantially the same, the fifth grid G
5 and 6th grid G6 adjustment is ga, 4th grid G4
By setting the adjustment of the fifth grid G5 to gb, γ = gb / (ga + gb) can be expressed.

In the above equation, ω · Ca · R, that is, 2π · f
Since the value of Ca · R changes at the frequency f of the dynamic focus voltage, the capacitance Ca and the resistance value R are appropriately selected and the horizontal deflection frequency fH is used to determine the fifth grid G5.
The voltage ed induced in the voltage can be set appropriately.
That is, it is possible to correct the astigmatism of the deflection magnetic field by generating a potential difference between the fifth grid G5 and the sixth grid G6 and forming a multipole lens between the fifth and sixth grids G5 and G6. is there.

That is, if 2πfHCaR >> 1, then approximately γ (= Ca / (Ca + Cb)) times the AC component Vd of the dynamic focus voltage applied to the fifth grid G5 and the sixth grid G6. Can be superimposed. For example, when Ca = Cb, as shown in FIG.
50% (50% Vd) of the parabolic voltage Vd which changes in synchronization with the deflection of the electron beam can be superposed on the electrodes of the fifth grid G5, and the voltage of the fifth grid G5 is shown by the curve 33. And the sixth grid G indicated by the curve 34
The potential difference between the fifth grid G5 and the sixth grid G6 can be increased in accordance with the deflection of the electron beam by changing the voltage in synchronization with the dynamic focus voltage applied to the sixth grid G5.

Therefore, the resistance value R, the capacitance between the electrodes, and the frequency f of the dynamic voltage are selected as described above, and the opposing beam passage holes of the fifth and sixth grids G5 and G6 are shown in FIG. By configuring as shown in a) and (b), the action of converging the multipole lens formed between the fifth and sixth grids G5 and G6 in the horizontal direction and diverging in the vertical direction is deflected by the electron beam. Accordingly, the focusing action of the final focusing lens EL can be weakened at the same time, and astigmatism of the horizontal deflection magnetic field can be corrected. Note that TH is one cycle of horizontal deflection.

That is, assuming that 2π · fH · Ca · R >> 1, the fifth and sixth grids G are formed as in the previous embodiment.
The action of focusing and diverging in the horizontal direction of the multipole lens formed between 5 and G6 can be increased in accordance with the deflection of the electron beam, and at the same time, the focusing action of the final focusing lens EL can be weakened to reduce the horizontal deflection magnetic field. The astigmatism can be corrected.

Therefore, by setting the same as in the previous embodiment, R ≧ 20.9 MΩ and the resistance value R of the first resistor 221 connecting the fifth grid G5 and the sixth grid G6 is set to 20.9. By setting it to MΩ or more, it is possible to induce about 50% of the dynamic focus voltage applied to the sixth grid G6 to the fifth grid G5 without practically causing the problem of phase difference.

Next, still another embodiment of the present invention will be described. FIG. 8 (corresponding to claim 4) shows the electron gun. This electron gun is the sixth electron gun of the embodiment shown in FIG.
A cylindrical intermediate electrode Gm is arranged between the grid and the seventh grid. The three cathodes K are arranged in a line in the horizontal direction (H-axis direction), and the heaters H for individually heating these cathodes K. The first to third grids G1 to G3, the fourth grid G4 (first grid), the fifth grid G5 (second grid), the fifth grid G5, the second grid, which are sequentially arranged in the phosphor screen direction at a predetermined distance from the cathode. 6 grid G6
It has a (third grid), an intermediate electrode Gm (fourth grid), and a seventh grid G7 (fifth grid).
In this electron gun, the fifth grid G5 and the sixth grid G6 are electrically connected to each other via a first resistor 221 arranged inside the tube, close to the electron gun.
And the intermediate electrode Gm are electrically connected to each other through the second resistor 222, and the intermediate electrode Gm and the seventh grid G7 are the third
It is connected through the resistor 223.
The other structure is the same as that of the electron gun of the embodiment shown in FIG. 6, and therefore the same parts are designated by the same reference numerals and the description thereof is omitted.

In this electron gun 21, an anode high voltage Eb of 25 to 35 kV is applied to the seventh grid G7 from a high voltage power source through an anode terminal 31 provided on the funnel. Intermediate electrode Gm and sixth and third grids G connected in the tube
6 and G3 have a sixth grid G6 and an intermediate electrode G, respectively.
The second resistor 222 connected to m, the third electrode 223 connected to the intermediate electrode Gm and the seventh grid G7, and the variable resistor 50 arranged outside the tube form the seventh grid G.
The anode high voltage Eb supplied to 7 is resistance-divided, and 50 to 80% of the anode high voltage Eb is applied to the intermediate electrode Gm, and about 20 to 35% of the voltage is applied to the sixth and third grids G6 and G3. . In particular, the sixth and third grids G6 and G3 have a reference voltage Vf of about 20 to 35% of the anode high voltage Eb.
(DC voltage), a dynamic focus voltage in which a parabolic voltage Vd that changes in synchronization with the deflection of the electron beam supplied from the electron gun power source is superimposed is applied to this reference voltage Vf. The fifth, second and first grids G5
, G2, G1 and the cathode K are applied with the same voltage as that of the electron gun of the embodiment shown in FIG.

As a result, in the electron gun 21, the electron emission from the cathode K is controlled by the cathode K and the first to third grids G1 to G3, and the emitted electrons are accelerated and focused to form an electron beam. Electron beam generator GE
Are formed by the third to seventh grids G3 to G7,
A main electron lens unit ML that focuses the electron beam on the phosphor screen is formed. In the main electron lens portion ML, substantially vertical electron beam passage holes 24a, 24b,
A multipole lens QL is formed between the fifth grid G5 formed with 24c and the sixth grid G6 formed with substantially horizontally long electron beam passage holes 25a, 25b, 25c, and the sixth pole G6 and the sixth grid G6 are formed. The final focusing lens EL is formed between the 7th grid G7 and the 7th grid G7. This final focusing lens EL
The intermediate electrode Gm is interposed between the sixth grid G6 and the seventh grid G7, thereby forming a large aperture electron lens in which the electric field is substantially expanded.

When the electron gun is constructed as described above, the multipole lens formed between the fifth grid G5 and the sixth grid G6 operates in the same manner as the electron gun of the embodiment shown in FIG. Corrects the astigmatism of the deflection magnetic field. Furthermore, this multipole lens can be made to have a selecting action according to the deflection frequency. Moreover, by connecting the sixth grid G6 to the variable resistor 26 provided outside the tube, a medium voltage can be easily supplied, and the circuit cost of the color picture tube device can be greatly reduced. Furthermore, since the final focusing lens is a large-diameter electron lens, spherical aberration is reduced, and the electron beam can be well focused on the phosphor screen. As a result, it is possible to obtain a highly reliable color picture tube device having a high resolution over the entire screen, excellent withstanding voltage characteristics.

In the above-described embodiments, the electron beam gun having the axially symmetric BPF type electron gun and the extended electric field type electron lens as the final focusing lens has been described, but the present invention is limited to these electron guns. However, the present invention can also be applied to a color picture tube device equipped with other symmetric electron lenses, asymmetric electron lenses, and an electron gun including an electron lens combining these electron lenses.

[0056]

According to the present invention, an electron gun having a main electron lens portion formed of a plurality of grids for focusing at least one electron beam emitted from an electron beam generating portion on a target, and an electron gun emitted from this electron gun. At least one cathode and a plurality of grids, and at least two adjacent grids of the plurality of grids are arranged in the tube. Connected by a resistor, a non-circular electron beam passage hole is formed in the facing surface of the adjacent grid, and a dynamic voltage that changes in synchronization with the deflection of the electron beam is applied to at least one of the adjacent grids. For a color picture tube device equipped with an electron gun, the capacitance between grids connected by resistors and the resistance of the resistors By setting the value and the frequency of the dynamic voltage synchronized with the horizontal deflection so as to satisfy a predetermined relationship, it is possible to reduce the astigmatism of the deflection magnetic field by only supplying one medium voltage from the outside of the tube to the electron gun. It becomes possible to correct. Furthermore, the multipole lens that corrects the astigmatism can be made to have a selective action according to the deflection frequency, and the resolution is high over the entire screen, and it has excellent withstand voltage characteristics and is highly reliable and high performance. It can be a color picture tube device.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an electron gun according to an embodiment of the present invention.

FIG. 2 (a) is a sixth view of the fifth grid of the electron gun.
The figure which shows the shape of the electron beam passage hole of the surface which opposes a grid, and FIG.2 (b) is a figure which shows the shape of the electron beam passage hole of the surface which opposes the 5th grid of 6th grid.

FIG. 3 is a diagram showing a configuration of a color picture tube device in one embodiment of the present invention.

FIG. 4 is an electrical equivalent circuit diagram of fourth, fifth and sixth grids of the electron gun.

FIG. 5 is a diagram for explaining voltage waveforms applied to fifth and sixth grids of the electron gun.

FIG. 6 is a diagram showing a structure of an electron gun according to another embodiment of the present invention.

FIG. 7 is an electrical equivalent circuit diagram of fourth, fifth and sixth grids of the electron gun.

FIG. 8 is a diagram showing a structure of an electron gun in still another embodiment of the present invention.

FIG. 9 is a diagram showing a configuration of a conventional color picture tube device.

10A is a diagram for explaining the action of a pincushion-type horizontal deflection magnetic field on an electron beam, FIG.
0 (b) is a diagram showing the shape of the resulting beam spot on the phosphor screen.

FIG. 11 (a) is a diagram showing a structure of a conventional improved electron gun, and FIG. 11 (b) shows a shape of an electron beam passage hole on a surface of the third grid opposed to the fourth grid. Figure,
FIG. 11C is a diagram showing the shape of the electron beam passage holes on the surface of the fourth grid facing the third grid.

FIG. 12 is a view for explaining the operation of the main electron lens unit of the improved electron gun.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Panel 3 ... Phosphor screen 8 ... Deflection yoke 20B, 20G, 20R ... 3 Electron beam 21 ... Electron gun 22 ... Resistor 24a, 24b, 24c ... Electron beam passage hole 25a, 25b, 25c ... Electron beam passage hole 27 ... Anode terminal 29 ... Stem 30 ... Stem pin EL ... Final focusing lens K ... Cathode G1 ... First grid G2 ... Second grid G3 ... Third grid G4 ... Fourth grid G5 ... Fifth grid G6 ... Sixth grid G7 ... 7-grid GE ... Electron beam generating section ML ... Main electron lens section QL ... Multipole lens 221 ... First resistor 222 ... Second resistor 223 ... Third resistor 50 ... Variable resistor EL ... Final focusing lens K ... Cathode Gm ... Intermediate electrode GE ... Electron beam generation part ML ... Main electron lens part QL ... Multipole lens

Claims (5)

[Claims] 1. An electron gun having a main electron lens section formed of a plurality of grids for focusing at least one electron beam emitted from an electron beam generating section on a target, and an electron beam emitted from this electron gun. At least a deflection yoke that generates a magnetic field for deflection scanning on a target, the electron gun includes at least one cathode and a plurality of grids, and at least two adjacent grids of the plurality of grids are arranged in a tube. And an electron beam passing hole having a non-circular shape is formed in the facing surface of the adjacent grids, and a dynamic voltage that changes in synchronization with the deflection of the electron beam is applied to at least one of the adjacent grids. In a color picture tube device including a gun, the plurality of grids of the electron gun are arranged from the cathode side. At least consists of first to fourth grids arranged in Getto direction, the first to third grids are adjacent to said fourth grid is applied with an anode high voltage,
A dynamic voltage in which a voltage that changes in synchronization with the deflection of the electron beam is superimposed on a DC voltage that is lower than the anode high voltage is applied to the third grid, and the second grid and the third grid are A voltage lower than the voltage of the second grid is applied to at least the first grid connected via a resistor arranged in the tube, and a deflection aberration is generated between the second and third grids. Compensating multipole lens forming means is provided, and electrostatic capacitance Ca between the third grid and the second grid and electrostatic capacitance Cb between the second grid and the first grid. , Where R is the resistance value of the resistor, fH is the frequency of the dynamic voltage synchronized with horizontal deflection, and pi is π ² · fH · Ca · R ≧ 13 · (1-γ) where γ = Ca In the relationship of / (Ca + Cb) Color picture tube apparatus according to claim Rukoto. 2. An electron gun having a main electron lens portion formed of a plurality of grids for focusing at least one electron beam emitted from an electron beam generating portion on a target, and an electron beam emitted from this electron gun. At least a deflection yoke that generates a magnetic field for deflection scanning on a target, the electron gun includes at least one cathode and a plurality of grids, and at least two adjacent grids of the plurality of grids are arranged in a tube. And an electron beam passing hole having a non-circular shape is formed in the facing surface of the adjacent grids, and a dynamic voltage that changes in synchronization with the deflection of the electron beam is applied to at least one of the adjacent grids. In a color picture tube device including a gun, the plurality of grids of the electron gun are connected to the cathode through the cathode. At least first to seventh grids arranged in the get direction, the first to sixth grids are adjacent to each other, an anode high voltage is applied to the seventh grid, and a sixth grid is higher than the anode high voltage. Also, a low DC voltage is applied with a dynamic voltage in which a voltage that changes in synchronization with the deflection of the electron beam is applied, and the fifth grid is at least connected to the sixth grid via a resistor arranged in the tube,
A multipole lens forming unit that corrects a deflection aberration is provided between the fifth and sixth grids, and a voltage lower than the voltage of the sixth grid is applied to the fourth grid, and the fourth grid and the second grid are applied. The grids are connected in a pipe, a voltage lower than that of the fourth grid is applied to the first grid, a capacitance Ca between the sixth grid and the fifth grid, and a fifth grid. When the electrostatic capacitance Cb with the fourth grid, the resistance value R of the resistor, and the frequency fH of the dynamic voltage synchronized with the horizontal deflection are used, and the circular constant is π, then π ² · fH · Ca · R ≧ 13 * (1- [gamma]) However, a color picture tube device characterized by the relationship of [gamma] = Ca / (Ca + Cb). 3. An electron gun having a main electron lens portion formed of a plurality of grids for focusing at least one electron beam emitted from an electron beam generating portion on a target, and an electron beam emitted from this electron gun. At least a deflection yoke that generates a magnetic field for deflection scanning on a target, the electron gun includes at least one cathode and a plurality of grids, and at least two adjacent grids of the plurality of grids are arranged in a tube. And an electron beam passing hole having a non-circular shape is formed in the facing surface of the adjacent grids, and a dynamic voltage that changes in synchronization with the deflection of the electron beam is applied to at least one of the adjacent grids. In a color picture tube device including a gun, the plurality of grids of the electron gun are connected to the cathode through the cathode. At least first to fourth grids arranged in the get direction, the first to third grids are adjacent to each other, and the second and third grids are connected by a first resistor, The third and fourth grids are connected by the second resistor connected to the first resistor, and the first grid is connected to the first resistor.
A predetermined voltage is applied to the grid, an anode high voltage is applied to the fourth grid, a voltage supply means is connected to the third grid outside the tube, and the voltage is changed in synchronization with the deflection of the electron beam. And a capacitance Ca between the third grid and the second grid is provided between the second and third grids by providing a multipole lens forming means for correcting deflection aberration. , Capacitance Cb between the second grid and the first grid, a resistance value R of the first resistor, and a frequency fH of a dynamic voltage synchronized with horizontal deflection,
When the circular constant is π, π ² · fH · Ca · R ≧ 13 · (1-γ), where γ = Ca / (Ca + Cb). 4. An electron gun having a main electron lens portion formed of a plurality of grids for focusing at least one electron beam emitted from an electron beam generating portion on a target, and an electron beam emitted from this electron gun. At least a deflection yoke that generates a magnetic field for deflection scanning on a target, the electron gun includes at least one cathode and a plurality of grids, and at least two adjacent grids of the plurality of grids are arranged in a tube. And an electron beam passing hole having a non-circular shape is formed in the facing surface of the adjacent grids, and a dynamic voltage that changes in synchronization with the deflection of the electron beam is applied to at least one of the adjacent grids. In a color picture tube device including a gun, the plurality of grids of the electron gun are connected to the cathode through the cathode. At least first to fifth grids arranged in the get direction, the first to third grids are adjacent to each other, and the second and third grids are connected by a first resistor, The third and fourth grids are connected by a second resistor, the fourth and fifth grids are connected by a third resistor, a predetermined voltage is applied to the first grid, and the fifth grid is connected. An anode high voltage is applied to the grid, a voltage supply means is connected to the third grid outside the tube, and a dynamic voltage that changes in synchronization with the deflection of the electron beam is applied to the second grid. A multipole lens forming means for correcting deflection aberration is provided between the grids, and the capacitance Ca between the third grid and the second grid, the second grid and the first grid, Capacitance C between , The frequency fH of the first resistor of the resistance value R, the dynamic voltage synchronized with the horizontal deflection,
When the circular constant is π, π ² · fH · Ca · R ≧ 13 · (1-γ), where γ = Ca / (Ca + Cb). 5. The color picture tube device according to any one of claims 1 to 4, wherein: γ = gb / (ga + gb), where the intervals between the grids forming the capacitances Ca and Cb between the grids are ga and gb, respectively. ) A color picture tube device characterized by the following relationship.